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Monkeypox virus

The Monkeypox virus (MPXV) is an enveloped, double-stranded DNA virus measuring 200-250 nm, belonging to the genus Orthopoxvirus within the family Poxviridae, which also includes the variola virus responsible for smallpox.^[1] It causes mpox, a zoonotic viral disease characterized by fever, lymphadenopathy, and a progressive rash, with symptoms resembling a milder form of smallpox but distinguished by prominent lymph node swelling.^[2] First isolated in 1958 from sick monkeys in a Danish laboratory during vaccine research, the virus was named after its initial detection in simian hosts, though its natural reservoirs are likely African rodents such as rope squirrels and giant pouched rats.^[1]^[3] Endemic to Central and West Africa, MPXV circulates in two primary clades: the less virulent West African clade (fatality rate ~1%) and the more severe Congo Basin clade (fatality rate up to 10%), with human infections historically sporadic and linked to bushmeat hunting or contact with infected wildlife.^[1] Transmission to humans occurs via direct contact with lesions, bodily fluids, or contaminated materials from infected animals or persons, as well as through respiratory droplets during prolonged close contact; recent molecular evidence has confirmed efficient sexual transmission in certain outbreaks.^[2] The virus replicates in the host cell cytoplasm, with an incubation period of 7-21 days, followed by prodromal symptoms like headache and myalgia before the rash appears, typically resolving in 2-4 weeks with supportive care.^[1] Notable for its genomic size of approximately 197 kb encoding around 181 proteins, MPXV demonstrates genetic divergence between clades that correlates with virulence and geographic distribution, underscoring its evolutionary adaptation within orthopoxviruses.^[1] While vaccination with smallpox vaccines provides cross-protection, the decline in routine immunization post-eradication has increased susceptibility, highlighting the virus's potential for sustained endemicity and occasional exportation beyond Africa.^[2]

Virology

Classification and taxonomy

The Monkeypox virus is classified within the realm Varidnaviria, kingdom Bamfordvirae, phylum Nucleocytoviricota, class Pokkesviricetes, order Chitovirales, family Poxviridae, subfamily Chordopoxvirinae, genus Orthopoxvirus, and species Orthopoxvirus monkeypox.^[4] This taxonomic placement aligns with the International Committee on Taxonomy of Viruses (ICTV) standards, positioning it among other orthopoxviruses such as Variola virus (smallpox) and Vaccinia virus.^[5] The species designation reflects its double-stranded DNA genome and brick-shaped virion morphology characteristic of poxviruses, which replicate in the host cell cytoplasm rather than the nucleus.^[6] The genus Orthopoxvirus comprises 13 recognized species, with O. monkeypox distinguished by its zoonotic potential and geographic association with African rodent reservoirs, though human infections have expanded globally.^[7] Taxonomic revisions, including the 2022 ICTV updates to higher-level categories like phylum Nucleocytoviricota, incorporate genomic and phylogenetic data emphasizing shared replication strategies and host range among chordopoxviruses.^[8] The virus's common name derives from its initial isolation in 1958 from a captive crab-eating macaque (Macaca fascicularis) in a Denmark laboratory, with the first human case reported in 1970 in the Democratic Republic of the Congo.00055-5/fulltext) Despite WHO efforts in 2022 to rename the disease "mpox" for sensitivity reasons, the viral species retains its ICTV-approved nomenclature, Orthopoxvirus monkeypox, to maintain scientific consistency.^[9]

Virion structure and genome

The monkeypox virus (MPXV), an orthopoxvirus, produces brick-shaped or ovoid virions measuring approximately 200–250 nm in length and 200 nm in width.^[10] ^[7] These enveloped particles feature a biconcave core enclosing the genome, flanked by two lateral bodies, and surrounded by a lipoprotein outer membrane exhibiting a geometrically corrugated surface with tubular or filamentous projections.^[11] ^[10] Two infectious forms exist: the mature virion (MV), which is brick-shaped and extracellular, and the enveloped virion (EV), which possesses an additional outer envelope derived from the host cell and facilitates cell-to-cell spread.^[1] MPXV possesses a linear, double-stranded DNA genome of approximately 197 kilobase pairs (kbp), ranging from 196 to 211 kbp across strains, encoding around 190–200 open reading frames (ORFs).^[12] ^[13] The genome termini consist of covalently closed hairpin loops and inverted terminal repeats (ITRs) of variable length, which contain multi-copy genes involved in DNA replication, transcription, and immune modulation.^[14] ^[12] The central region of the genome is highly conserved among orthopoxviruses, harboring essential genes for core replication machinery, virion assembly, and basic metabolism, while the terminal regions exhibit greater variability, including genes that determine host range and virulence factors such as immunomodulatory proteins.^[15] ^[16] This organization reflects evolutionary adaptations, with the ITRs facilitating recombination and expansion-contraction dynamics observed in recent outbreaks.^[17]

Replication cycle

The replication cycle of monkeypox virus (MPXV), an orthopoxvirus, transpires exclusively in the host cell cytoplasm, circumventing nuclear involvement typical of most DNA viruses. This cytoplasmic localization enables formation of discrete replication compartments known as viral factories, which compartmentalize viral processes and evade host nuclear defenses.^[15]^[18] The cycle initiates with virion attachment to host cells, where extracellular enveloped virions (EEV) bind glycosaminoglycans on mucous membranes or damaged skin, while intracellular mature virions (IMV) engage receptors via proteins including I5L, E8L, and A43R. Entry proceeds through plasma membrane fusion for EEV or endocytosis for IMV, delivering the viral core into the cytoplasm.^[15]^[10] Uncoating follows, entailing core transport along microtubules to the perinuclear region at ~52 μm/min, coupled with ubiquitination and proteasomal degradation of outer capsid layers to expose the genome.^[15]^[18] Early-phase transcription ensues immediately upon genome release, driven by virally encoded DNA-dependent RNA polymerase transcribing ~50% of the genome into mRNAs for proteins supporting DNA synthesis, immune evasion, and intermediate transcription factors. DNA replication, commencing within ~2 hours post-infection, occurs in cytoplasmic factories using the dsDNA genome as template; the viral polymerase F8, along with processivity factors, generates head-to-tail concatemers resolved into monomeric genomes via recombination or resolution mechanisms.^[15]^[18]^[19] Post-replication, intermediate genes produce enzymes and substructural components, followed by late gene expression yielding virion assembly proteins. Immature virions (IV) assemble as crescent membranes encapsulating DNA concatemers in factories, maturing via protease cleavage into brick-shaped IMV; a subset acquires dual envelopes from endoplasmic reticulum and trans-Golgi membranes to form intracellular enveloped virions (IEV).^[15]^[18]^[10] Egress involves microtubule- or actin tail-mediated transport of IEV (~60 μm/min) to the plasma membrane, yielding cell-associated enveloped virions or EEV released extracellularly; alternatively, IMV exit via cell lysis, perpetuating dissemination.^[15] This multi-form virion strategy enhances environmental stability and host-to-host transmission efficiency.^[18]

Genetic variants and clades

Clade I (West African lineage)

Clade I, previously referred to as the Congo Basin or Central African clade, represents one of the two primary genetic lineages of the monkeypox virus (MPXV), distinguished by its higher virulence and association with endemic circulation in Central African rainforests.^[20] This clade diverged phylogenetically from Clade II approximately 300–800 years ago, with genetic analyses indicating adaptations for sustained human-to-human transmission in certain contexts, including chains exceeding 10 generations in the Democratic Republic of the Congo (DRC).^[21] Unlike Clade II, Clade I exhibits specific genomic deletions and mutations, such as in genes modulating host immune evasion, contributing to its elevated case-fatality rate (CFR) of 1–10% in reported outbreaks.^[22] Endemic to countries including the DRC, Republic of the Congo, Central African Republic, and Gabon, Clade I primarily emerges through zoonotic spillovers from rodent reservoirs like rope squirrels and sun squirrels, with human cases often linked to bushmeat hunting and forest activities.^[23] In the DRC, where over 20,000 suspected cases and 1,000 deaths were reported in 2023–2024, Clade I has driven the majority of human infections, with subclade Ia predominant in rural zoonotic events and subclade Ib fueling urban outbreaks involving sexual networks and higher transmissibility.^[24] Phylogenetic studies reveal limited genetic drift in Clade I compared to West African lineages, suggesting ongoing evolutionary pressure from recurrent spillovers rather than isolated human adaptation.^[21] Subclades within Clade I, such as Ib, have emerged with enhanced human transmissibility; for instance, a 2024 outbreak in eastern DRC's mining regions involved a novel Ib lineage with over 400 confirmed cases, marked by genomic features enabling prolonged chains of infection beyond typical zoonotic patterns.^[23] Experimental data demonstrate Clade I's superior virulence in animal models, replicating up to 1,000 times more efficiently in human and primate cells than Clade II variants, correlating with clinical observations of more severe disease, including higher rates of secondary bacterial infections and complications in children.^[22] Vaccination with older smallpox vaccines provides partial cross-protection against Clade I, though efficacy wanes against more divergent strains, underscoring the need for updated orthopoxvirus countermeasures.^[25]

Clade II (Central and West African lineages)

Clade II of the monkeypox virus (MPXV) encompasses genetic lineages predominantly circulating in West Africa, with some variants reported in adjacent Central African regions such as Cameroon and Liberia.^[26]^[27] This clade is distinguished from Clade I by approximately 0.4–0.5% nucleotide divergence in conserved nonrepetitive genomic regions, along with differences in four large insertion/deletion areas that influence viral fitness and host adaptation.^[28] Subclades within Clade II include IIa, linked to endemic cases in West-Central Africa, and IIb, which emerged from Nigerian lineages and drove the 2022 global outbreak.^[29]^[30] Epidemiologically, Clade II infections in Central and West African countries exhibit lower case-fatality rates, typically 1–3%, compared to up to 10% for Clade I, attributable to reduced virulence factors such as attenuated immune evasion genes.^[25]^[31] In Nigeria, where Clade II has been endemic since at least 2017, outbreaks involve sporadic zoonotic spillovers from rodents, with limited human-to-human chains of fewer than five generations, contrasting with more sustained chains in Clade I-endemic areas.^[30] Recent Clade IIa cases in Liberia from 2023–2024 totaled over 200 confirmed infections, primarily among hunters exposed to bushmeat, highlighting ongoing sylvatic transmission in forested West African ecosystems.^[26] Genetically, Clade II lineages show adaptations for human transmission, including mutations in genes like F3L (encoding an ankyrin repeat protein) that may enhance immune modulation without the heightened lethality of Clade I variants.^[32] Phylogenetic analyses indicate Clade II divergence from a common ancestor with Clade I around the 19th century, with West African strains exhibiting higher genetic diversity due to recurrent animal reservoir recombinations.^[33] Surveillance data from 2017–2024 reveal no evidence of increased virulence in these lineages, though subclade IIb's global dissemination involved over 50 adaptive mutations facilitating sexual network spread.^[32]^[30]

Emerging subclades and mutations

In 2023, a novel subclade Ib within Clade I of the monkeypox virus (MPXV) emerged in the Democratic Republic of the Congo (DRC), characterized by distinct genetic mutations that distinguish it from the predominant Clade Ia.^[28] This subclade has been linked to expanded human-to-human transmission beyond traditional zoonotic patterns, with cases reported in neighboring countries including Burundi, Rwanda, and Uganda by mid-2024.00294-6/fulltext) Genomic analyses reveal that Clade Ib genomes exhibit approximately 329 mutations relative to ancestral strains, including a mutational pattern driven by cytosine deamination via host APOBEC3 enzymes, though low overall APOBEC3 signature counts in some Ia strains suggest recurrent zoonotic introductions rather than solely human adaptation.^[34] ^[35] Clade Ib mutations include novel substitutions potentially enhancing viral replication efficiency and virulence, such as those in genes affecting host immune evasion and transmission dynamics, though direct causality remains under investigation without conclusive evidence of heightened severity beyond epidemiological patterns.^[36] ^[37] For instance, sequencing of Clade Ib strains from 2023–2024 outbreaks identified 28–47 unique mutations in key regions, with 68–72% lacking classic APOBEC3 signatures, indicating diverse evolutionary pressures including possible drug resistance markers like those conferring tecovirimat tolerance in isolated variants.00294-6/fulltext) ^[38] These changes have facilitated subclade spread across borders, with imported cases confirmed in non-endemic regions by November 2024, prompting enhanced surveillance.00276-7/fulltext) Concurrently, Clade IIb—the lineage responsible for the 2022 global outbreak—continues to evolve through sublineages like B.1, accumulating APOBEC-associated mutations indicative of prolonged human circulation.^[33] Studies from 2023–2025 document up to 95.3 mutations per strain in later-phase IIb isolates, a 1.2-fold increase over early 2022 samples, primarily in non-coding regions but with functional implications for immune modulation and sexual transmission efficiency.^[39] However, MPXV's double-stranded DNA genome confers relative stability, limiting rapid adaptive shifts compared to RNA viruses, and no widespread evidence supports dramatically altered pathogenicity from these mutations alone.^[30] Ongoing genomic surveillance, including whole-genome sequencing of over 100 Clade IIb strains, underscores the need for monitoring extragenic variations that predominate across clades.^[29]

Origins and evolutionary history

Natural reservoirs and zoonotic origins

The natural reservoir of monkeypox virus (MPXV) remains unidentified despite extensive serological surveys, virus isolations, and ecological modeling in endemic regions of Central and West Africa.^[40]^[41] African rodents, particularly species inhabiting tropical rainforests, are the leading candidates based on detections of viral DNA, live virus, and orthopoxvirus antibodies in wild populations.^[42] MPXV has been isolated from wild Funisciurus anerythrus (fire-footed rope squirrel) in the Democratic Republic of the Congo (DRC, then Zaire), with seroprevalence rates up to 25% reported in this and related squirrel species such as Heliosciurus spp. in forested areas near human settlements.^[42] Antibodies and viral DNA have also been found in Gambian pouched rats (Cricetomys gambianus), with 5% PCR positivity and 2% seropositivity in surveys from Ghana, and in African dormice (Graphiurus spp.), where up to 80% tested positive in some samples.^[42] These rodents occupy ecological niches overlapping with MPXV's known distribution, supporting their potential role in maintaining sylvatic cycles, though no single species has demonstrated sustained, asymptomatic circulation sufficient to confirm reservoir status.^[3] Zoonotic spillover of MPXV to humans originates from these wildlife reservoirs in the rainforests of Central and West Africa, where deforestation, hunting, and bushmeat trade increase contact opportunities.^[43] The virus was first detected in 1958 during an outbreak among captive monkeys imported from Africa to a research facility in Denmark, revealing its orthopoxvirus nature but not its natural host, as primates exhibit high mortality rather than chronic carriage.^[42] The inaugural human case occurred on September 15, 1970, in a 9-month-old boy in a rural village in the DRC's Équateur Province, identified during intensified smallpox surveillance; the child's exposure likely stemmed from direct contact with infected rodents or bushmeat, though the precise source was not confirmed.^[44]^[43] Subsequent human infections in endemic areas have been epidemiologically linked to handling wild animals, with genetic evidence indicating repeated independent spillovers rather than sustained human-to-human chains in early outbreaks.^[45] Ecological and phylogenetic data reinforce rodent-mediated origins, with recent studies identifying squirrels as key amplifiers: a 2024 analysis in the DRC detected MPXV in multiple squirrel species via environmental sampling and contact tracing, while niche modeling prioritizes F. anerythrus for its geographic congruence with human cases.02188-3/fulltext)^[3] Interspecies transmission among rodents, evidenced by the 2003 U.S. outbreak tracing to imported Gambian rats and dormice from Ghana, underscores the virus's broad host range and potential for export beyond Africa.^[42] Despite these findings, experimental infections reveal high lethality in many rodent models, complicating reservoir attribution, as true reservoirs typically support subclinical, persistent infection.^[42] Ongoing surveillance in wildlife continues to refine understanding, with no evidence of non-rodent reservoirs like primates fulfilling this role.^[46]

Phylogenetic evidence and divergence

Phylogenetic analyses of monkeypox virus (MPXV) genomes, derived from whole-genome sequencing of isolates primarily from human cases in endemic African regions, reveal a binary structure comprising two major clades: Clade I, associated with Central African lineages and higher virulence, and Clade II, linked to West African lineages with generally milder disease outcomes.^[47]^[48] These clades are distinguished by nucleotide substitutions across the ~197 kb double-stranded DNA genome, particularly in genes encoding virulence factors, immune evasion proteins, and host-range determinants, as evidenced by maximum-likelihood phylogenetic trees constructed using conserved orthopoxvirus regions.^[49] Subclades within Clade I include Ia (endemic Central African) and Ib (emergent, associated with 2023–2024 outbreaks), while Clade II encompasses IIa (West African) and IIb (the 2022 global outbreak lineage B.1).^[48]^[29] Bayesian phylogeographic modeling, incorporating temporal sampling from archival and contemporary sequences, estimates the divergence of Clade I and Clade II at approximately 560–860 years before present (95% highest posterior density: 450–960 years), aligning with medieval periods of ecological disruption in Central and West Africa potentially facilitating zoonotic establishment.^[47] This split predates documented human cases (first reported in 1970) and reflects geographic structuring, with Clade I showing tighter clustering in Central African Democratic Republic of the Congo sequences and Clade II exhibiting broader West African dispersal.^[21] Within-clade diversification is more recent; for instance, Clade IIb's most recent common ancestor (TMRCA) for the 2022 pandemic lineage traces to ~2017–2018, inferred from ~50 single-nucleotide polymorphisms (SNPs) distinguishing it from pre-2022 IIa strains, indicative of sustained cryptic human circulation rather than abrupt zoonotic spillover.^[50]^[51] Evidence of microevolution includes positive selection at sites in genes like OPG (orthopoxvirus growth factor) and SP1, potentially enhancing human adaptation, as detected via site-specific dN/dS ratios >1 in branch-site models across African endemic sequences.^[52] Global surveillance post-2022, encompassing >10,000 genomes, confirms ongoing divergence, with Clade I strains displaying higher intra-clade SNP diversity (~0.02–0.05%) compared to Clade IIb's lower variability (~0.01%), suggesting differing effective population sizes and recombination suppression typical of poxviruses.^[29] These patterns underscore MPXV's orthopoxvirus ancestry, diverging from variola virus ancestors millennia ago, but highlight recent anthropogenic drivers amplifying clade-specific radiations over natural reservoir dynamics.^[12]

Transmission dynamics

Zoonotic spillover mechanisms

Zoonotic spillover of monkeypox virus (MPXV) to humans occurs predominantly in endemic areas of Central and West Africa, where human activities intersect with infected wildlife populations.^[53] Primary transmission routes involve direct contact with infected animals, including exposure to blood, respiratory secretions, or vesicular lesions during hunting, trapping, skinning, or butchering.^[41] Bites or scratches from symptomatic animals can also facilitate viral entry through broken skin.^[40] Suspected amplifying or reservoir hosts include rodents such as African rope squirrels (Funisciurus spp.), from which MPXV has been isolated in natural settings, and Gambian pouched rats (Cricetomys gambianus), implicated in early detections.^[54] ^[55] Serological evidence and viral isolations from these species support their role in maintaining enzootic cycles, though the definitive reservoir host remains unidentified despite extensive sampling.^[3] ^[40] Ingestion of inadequately cooked bushmeat represents another key mechanism, with outbreaks traced to consumption of infected rodents or primates.^[56] In the Democratic Republic of the Congo, index cases in sporadic outbreaks from 1990 to 2000 were linked to handling of wild animals, underscoring bushmeat practices as a persistent risk factor.^[57] Genomic analyses of MPXV strains reveal multiple independent spillover events, indicating recurrent introductions from wildlife reservoirs without sustained human adaptation prior to recent clades.^[58] Environmental factors, such as deforestation and habitat encroachment, likely increase spillover frequency by enhancing human-wildlife interfaces, though direct causation requires further longitudinal studies.^[59] Absence of MPXV detection in some surveyed potential hosts, like certain shrews or porcupines, highlights gaps in understanding sylvatic transmission chains.^[60] Prevention hinges on reducing wildlife contact, yet challenges persist due to reliance on bushmeat in rural communities.^[61]

Human-to-human spread

Human-to-human transmission of monkeypox virus occurs mainly through direct physical contact with skin lesions, scabs, bodily fluids, or respiratory secretions from infected persons during the symptomatic phase, which spans from rash onset until scabs heal and a new layer of skin forms over the lesions.^[2]^[62] Close, prolonged interactions—such as those involving skin-to-skin contact, including sexual activity—predominate, with evidence from animal models and outbreak investigations indicating that the virus requires sufficient viral load and intimate exposure for efficient transfer, unlike highly aerosolized pathogens.^[63]00034-4/fulltext) In the 2022 global outbreak driven by clade IIb, transmission routes shifted toward sustained chains facilitated by sexual networks, particularly among men who have sex with men, where over 98% of cases in some datasets involved such contacts, though household and non-sexual close contacts also contributed, with secondary attack rates in UK households estimated at 4% overall (rising to higher risks with sexual exposure to the index case).^[64]^[65] Pooled data from prior outbreaks show household secondary attack rates ranging from 0% to 11%, averaging around 8% among unvaccinated contacts, with elevated risks (up to 11.7%) in unvaccinated children under 5 years exposed via shared living spaces.^[66]^[67] The basic reproduction number (R₀) across clades typically falls between 0.57 and 1.25, reflecting low inherent transmissibility reliant on behavioral and contact intensity factors rather than casual airborne spread.^[68] Endemic outbreaks in Central and West Africa historically feature short human-to-human chains (1–2 generations) punctuated by zoonotic introductions, limiting widespread propagation without repeated spillovers, whereas the 2022–2023 event demonstrated extended serial transmission in non-endemic regions due to high-contact social behaviors, though overall incidence declined without population-level immunity once targeted interventions reduced partner rates in affected networks.^[69]^[70] Evidence for fomite or indirect environmental transmission exists but remains secondary to direct contact, with no robust support for sustained aerosolization via fine particles in human settings.^[71] In ongoing clade I outbreaks as of 2025, household and community contacts continue to drive limited spread, underscoring the virus's dependence on close-proximity exposures over distant or ventilated dispersal.^[72]

Interspecies and environmental factors

Monkeypox virus (MPXV) primarily spills over to humans from infected animal hosts through direct contact with bodily fluids, lesions, or contaminated materials such as bushmeat during hunting, handling, or consumption, with rodents like Funisciurus squirrels (particularly F. anerythrus) and giant pouched rats identified as probable reservoirs based on niche overlap and phylogenetic data. ^[3] ^[73] The virus exhibits broad host tropism, infecting various mammals including primates, and can sustain interspecies transmission in captive settings, as evidenced by the 2003 United States outbreak where MPXV spread from imported African rodents to prairie dogs via close contact or fomites. ^[25] ^[74] Reverse zoonosis—human-to-animal transmission—remains a concern, potentially establishing new reservoirs outside endemic areas, though no definitive non-African animal reservoirs have been confirmed despite serological surveys in regions like Gabon yielding negative results. ^[75] ^[40] Environmental factors amplify zoonotic spillover by increasing human-animal interfaces, with deforestation and habitat fragmentation in Central and West African rainforests driving closer contact between humans and reservoir species through activities like bushmeat harvesting and agricultural expansion. ^[76] ^[77] Climatic variables, including temperature and rainfall, modulate transmission dynamics; lower temperatures enhance viral stability on surfaces, prolonging environmental persistence, while seasonal rainfall patterns correlate with rodent population fluctuations that facilitate outbreaks. ^[78] ^[79] MPXV demonstrates remarkable environmental resilience as a poxvirus, surviving desiccation and tolerating wider pH and temperature ranges than many enveloped viruses, with greater viability on porous surfaces like bedding compared to nonporous ones, thereby elevating fomite-mediated interspecies risks in endemic settings. ^[80] ^[81]

Pathogenesis

Infection process and viral entry

The monkeypox virus (MPXV), an orthopoxvirus, initiates infection primarily through direct contact with broken skin, mucous membranes, or the respiratory tract, where virions encounter susceptible host cells such as keratinocytes, fibroblasts, and dendritic cells.^[63] Initial viral attachment occurs via binding of envelope proteins on the mature virion (intracellular mature virus, IMV) to host cell surface glycosaminoglycans (GAGs), including heparan sulfate and chondroitin sulfate, as well as laminin and integrins, facilitating adhesion and proximity for subsequent entry.^[82] ^[83] Key MPXV proteins implicated in this process include homologs of vaccinia virus A27, A26, H2, and L1, which mediate electrostatic interactions and membrane destabilization, though specific receptor usage for MPXV remains incompletely characterized and may involve multiple redundant pathways unlike single-receptor tropism in some viruses.^[84] ^[10] Viral entry proceeds via pH-dependent endocytosis, macropinocytosis, or plasma membrane fusion, with the enveloped extracellular virion (EEV) form favoring dissemination while IMV drives localized infection; fusion requires an entry-fusion complex comprising at least eight core proteins (e.g., A28, A25, G9) that coordinate conformational changes for membrane merger and core release into the cytoplasm.^[72] ^[10] Once internalized, the viral core undergoes uncoating, exposing the double-stranded DNA genome for transcription and replication in the host cytoplasm, evading nuclear-dependent defenses; early gene expression produces factors that further suppress innate responses, enabling rapid amplification in local tissues before lymphatic spread.^[85] ^[84] This cytoplasmic lifecycle, conserved across orthopoxviruses, contrasts with nuclear-replicating DNA viruses and underscores MPXV's adaptation for efficient host cell hijacking without reliance on host replication machinery.^[83] Following cellular entry, MPXV exploits antigen-presenting cells like macrophages and dendritic cells for migration to draining lymph nodes, establishing primary viremia within 1-2 days post-inoculation and amplifying systemic dissemination; this process is modulated by viral inhibitors of interferon signaling, which dampen early antiviral states to promote unchecked replication.^[58] ^[63] Experimental models indicate that entry efficiency varies by host cell type and viral clade, with Clade I strains exhibiting potentially higher tropism for immune cells compared to Clade II, though human data remain limited to observational pathogenesis studies.^[86]

Clinical manifestations in humans

The incubation period for monkeypox virus infection in humans typically ranges from 5 to 21 days, with a median of 6 to 13 days.^[40] Initial prodromal symptoms, lasting 1 to 5 days, include fever (reported in 62-72% of cases), chills, headache (25-55%), myalgias (31-55%), backache, fatigue or malaise (23-57%), and notably, lymphadenopathy affecting cervical, inguinal, or submandibular nodes (56-86%), which distinguishes monkeypox from smallpox or varicella.^[87] These symptoms arise due to viral replication in lymphoid tissues following initial viremia.^[63] A characteristic rash emerges 1 to 3 days after prodrome onset, beginning as macules that progress to papules, vesicles, pustules, and scabs over 2 to 4 weeks, with lesions often painful or pruritic and distributed centrifugally on the face, trunk, and extremities.^[88] Total lesion counts vary from few to hundreds, with mucosal involvement (oral, genital, or anal) in up to 70% of 2022 outbreak cases, particularly anogenital ulcers or proctitis among men who have sex with men.^[89] ^[90] Upper respiratory symptoms such as pharyngitis or tonsillitis occur in some patients.^[63] Clinical severity differs by viral clade: Clade I (including subclades Ia and Ib) infections, endemic to central Africa, feature higher fever, more extensive rash, and case-fatality rates of 0.1-10.6%, while Clade II (including IIb in the 2022-2023 global outbreak) causes milder illness with fatality under 1% and reduced systemic symptoms.^[40] ^[91] In the 2022 outbreak, primarily Clade IIb, many cases were atypical with solitary or few lesions, minimal prodrome, and prolonged anal or genital symptoms, though 13% required hospitalization.^[89] ^[92] Complications, though uncommon in immunocompetent adults, include secondary bacterial skin infections, pneumonia, encephalitis, keratitis, and dehydration, with higher risks in children, pregnant individuals, and those with HIV or other immunosuppression; mortality is rare in Clade II but elevated in Clade I outbreaks.^[87] ^[93] Disease duration is usually 2 to 4 weeks, with full recovery following scab separation, though scarring or vision loss from ocular involvement persists in severe cases.^[81]^[94]

Disease in animal hosts

In presumed natural reservoir hosts, such as African rope squirrels (Funisciurus spp.) and African giant pouched rats (Cricetomys gambianus), monkeypox virus infections are typically subclinical or mild, characterized by limited viremia, minimal skin lesions, and no significant mortality, enabling viral persistence in wild populations without overt disease disruption.^[55] Serological surveys in endemic regions have detected antibodies in these rodents, but clinical cases are rare, suggesting adaptation that favors asymptomatic carriage over pathogenesis.^[42] In incidental or non-reservoir hosts, particularly non-human primates, the virus induces severe systemic disease. The pathogen was first identified in 1958 during an outbreak in captive crab-eating macaques (Macaca fascicularis) at a Danish laboratory, where it caused fever, respiratory distress, subcutaneous nodules progressing to pustules, generalized rash, and mortality rates exceeding 10% in affected colonies.^[42] Experimental aerosol exposure in cynomolgus macaques (Macaca fascicularis) replicates human-like pathogenesis, featuring fibrinonecrotic bronchopneumonia as the dominant lesion, alongside lymphoid necrosis, high viral loads in lung tissue, and death within 10-14 days post-infection.^[95] North American prairie dogs (Cynomys ludovicianus) demonstrate high susceptibility, as evidenced in the 2003 United States outbreak linked to imported African rodents; infected animals developed ocular and genital lesions, ulcerative dermatitis, pneumonitis, sepsis, and fatality rates approaching 100% in untreated cases, with efficient transmission via direct contact or fomites.^[42] Experimental intranasal, intradermal, or intraperitoneal inoculation confirms multi-route vulnerability, with peak viremia preceding severe lymphoproliferation and pulmonary edema.^[96] Other species show variable outcomes: California ground squirrels (Otospermophilus beecheyi) exhibit fulminant illness post-oropharyngeal exposure, including bacteremia, oropharyngeal ulceration, and death 6-9 days post-infection with recoverable virus from blood and mucosa.^[97] Domestic pigs experimentally infected intradermally develop cutaneous pustules, fever, and viremia, transmitting virus to uninoculated contacts via close proximity, indicating potential for interspecies spread in agricultural settings.^[98] During the 2022 global outbreak, mpox virus infected domestic dogs in human households, presenting with mild anogenital lesions and systemic shedding but no severe sequelae, representing the first documented canine cases outside Africa.^[99] These findings underscore host-specific differences in immune response and viral tropism, with non-adapted species experiencing amplified replication in skin, mucosa, and viscera.^[100]

Host-virus interactions

Innate and adaptive immunity

The innate immune response to monkeypox virus (MPXV) infection primarily involves recognition of viral pathogen-associated molecular patterns (PAMPs) by host pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) and RIG-I-like receptors (RLRs), leading to activation of signaling pathways that induce type I interferons (IFNs) and pro-inflammatory cytokines.^[101] MPXV, however, employs multiple evasion strategies, including soluble IFN decoy receptors and inhibitors of IFN-induced signaling, such as the viral protein MOPICE (MPXV inhibitor of complement enzymes), which disrupts the JAK-STAT pathway and limits antiviral gene expression.^[102] Natural killer (NK) cells play a role in early control by lysing infected cells, but MPXV impairs NK function through downregulation of chemokines like CCR5, CXCR3, and CCR6, reducing IFN-γ and TNF-α secretion.00606-5/fulltext) Macrophages and dendritic cells contribute to innate defense via phagocytosis and antigen presentation, yet MPXV-encoded proteins like A52R homologs antagonize NF-κB and IRF3 activation, suppressing cytokine production and delaying inflammation.^[103] Transition to adaptive immunity occurs as innate responses bridge to T and B cell activation, with MPXV infection eliciting CD4+ and CD8+ T cell responses targeting viral antigens, particularly those from early genes expressed prior to genome replication.^[84] Neutralizing antibodies develop against envelope proteins like A27L and L1R, correlating with protection in animal models, as evidenced by reduced viral loads in vaccinated nonhuman primates.^[104] The adaptive response is influenced by the virus's CrmA-like serpin and other modulators that inhibit apoptosis in infected cells, prolonging antigen exposure but also enabling viral dissemination before peak T cell effector function around days 7-14 post-infection.^[103] Memory B and T cells provide long-term immunity, with cross-protection observed from prior smallpox vaccination; for instance, JYNNEOS vaccine induces robust MPXV-specific IgG and T cell responses, peaking 2-4 weeks post-dose and persisting for at least 6 months.^[84] In clade IIb infections, early adaptive responses, including polyfunctional CD8+ T cells, associate with milder disease severity in murine models.^[105] Host genetic factors, such as polymorphisms in IFN pathway genes, modulate susceptibility, with impaired innate signaling linked to higher viral replication in vitro.^[101] Clade differences influence immune dynamics; clade I strains exhibit stronger innate evasion via enhanced IFN antagonists compared to clade II, potentially contributing to higher fatality rates (up to 10% vs. <1%).^[106] Overall, effective control requires coordinated innate priming and adaptive effector functions, though MPXV's genome encodes over 200 immunomodulatory proteins that tilt the balance toward viral persistence in susceptible hosts.^[103]

Immune evasion strategies

The monkeypox virus (MPXV), an orthopoxvirus, employs multiple strategies to evade host immune responses, primarily through virally encoded proteins that target innate antiviral pathways and adaptive immunity components. These mechanisms, conserved across orthopoxviruses but with clade-specific variations, enable prolonged viral replication and dissemination despite host defenses. Central African clade MPXV exhibits more robust evasion capabilities than the less virulent West African clade, partly due to intact genes for complement inhibition absent or truncated in the latter.^[84] In evasion of innate immunity, MPXV prominently utilizes the F3 protein, a homologue of vaccinia virus E3L, which binds double-stranded RNA to sequester pathogen-associated molecular patterns and inhibit activation of pattern recognition receptors such as PKR, MDA-5, RIG-I, and OAS, thereby suppressing type I interferon (IFN) production and downstream antiviral signaling.^[107]^[103] The B16 protein further antagonizes IFNβ signaling by disrupting JAK-STAT pathways, while BCL-2-like inhibitors (e.g., A47, B13, P1, C6, D11) block NF-κB and IRF3 activation to limit proinflammatory cytokine expression.^[84] Additional proteins include SPI-2 (B12R), which inhibits apoptosis via caspase targeting to preserve infected cells; CrmB, a soluble TNF receptor decoy that neutralizes TNF and lymphotoxin; and ankyrin-repeat proteins (e.g., J3L, D1L) that prevent NF-κB nuclear translocation.^[84] For natural killer (NK) cells, the N3R-encoded MPXV OMCP mimics MHC class I to engage NKG2D inhibitory receptors, while an IL-18 binding protein suppresses NK cytotoxic activity.^[84] The Central African clade uniquely encodes D14 (MOPICE), a complement control protein that inhibits the classical and lectin pathways, enhancing evasion in non-human primates compared to variola virus, which lacks this ORF.^[84] Adaptive immunity evasion focuses on impairing T-cell surveillance and humoral responses. MPXV induces MHC-independent unresponsiveness in CD4+ and CD8+ T cells by blocking receptor-mediated activation in infected antigen-presenting cells, preventing cytokine release (e.g., IFNγ, TNFα) and enabling cell-associated viremia in monocytes that disseminates virus extracellularly.^[107]^[103] The B10R protein disrupts MHC class I trafficking to the cell surface, reducing peptide presentation to cytotoxic T cells.^[84] Antibody evasion occurs via enveloped virion shielding and low systemic free-virus levels, limiting neutralizing antibody access, though cross-reactive antibodies from prior orthopoxvirus exposure (e.g., vaccinia) can partially mitigate this.^[103] These strategies collectively delay adaptive priming, contributing to MPXV's prolonged incubation period of 6–13 days and higher transmissibility in 2022 outbreaks relative to historical variola.^[84]

Factors influencing severity

The severity of mpox disease varies significantly based on the viral clade, with clade I (including subclades Ia and Ib) associated with more severe illness and higher case-fatality rates (CFRs) compared to clade II (subclades IIa and IIb). Historical data indicate clade I CFRs up to 10.6% (95% CI 8.4–13.3%), while clade II CFRs are under 1%.^[31]^[108] Clade Ib, a recently emerged variant of clade I, has been linked to outbreaks in Africa with CFRs around 3–6% in reported cases as of 2024, though underreporting may inflate these figures.^[40] In contrast, the 2022 global outbreak, driven primarily by clade IIb, resulted in milder presentations with CFRs below 0.1% in well-resourced settings.^[109] Host immune status is a primary determinant of disease outcome, particularly immunosuppression from advanced HIV infection. Persons living with HIV, especially those with CD4 counts below 200 cells/mm³, face substantially elevated risks of severe mpox, including necrotizing lesions, prolonged viral shedding (up to 11 months in some cases), and mortality rates up to 14-fold higher than in non-HIV-infected individuals.^[110]^[111]^[112] However, people with HIV who maintain adequate immune function (e.g., CD4 >350 cells/mm³ and suppressed viral loads) do not exhibit heightened severity risks beyond the general population.^[113] Broader immunocompromising conditions, such as those from chemotherapy or organ transplantation, similarly increase susceptibility to complications like disseminated infection and secondary bacterial superinfections. Other host factors include young age and certain dermatologic or physiologic states. Children under 1 year old are at elevated risk for severe disease due to immature immune responses, with historical CFRs exceeding 3% in endemic settings. A history of atopic dermatitis (eczema) predisposes individuals to widespread rash and bacterial complications owing to disrupted skin barrier function. Pregnant women face heightened risks of fetal loss and maternal complications, though data remain limited to case reports from endemic regions. No consistent evidence links sex, body mass index, or prior smallpox vaccination status directly to severity variations across clades, though vaccination (e.g., with JYNNEOS or ACAM2000) mitigates outcomes in exposed individuals by reducing viral replication.^[114]

Epidemiology

Endemic patterns in Africa

The mpox virus has been endemic to Central and West Africa since its identification in humans, with the first confirmed human case reported in 1970 in the Democratic Republic of the Congo (DRC). Cases arise primarily through zoonotic spillover from infected wildlife reservoirs, such as rope squirrels and giant pouched rats, though human-to-human transmission via close contact sustains limited outbreaks.^[115] Endemic transmission occurs year-round in equatorial regions, where consistent climate supports persistent viral circulation, contrasting with more seasonal patterns farther from the equator.^[116] Two distinct genetic clades predominate: Clade I (formerly Congo Basin), circulating in Central Africa, exhibits higher virulence with case fatality rates (CFR) of 5-10%, while Clade II (West African) shows lower severity, with CFR under 1%.^[31] Clade I drives the bulk of endemic cases, particularly in the DRC, where over 14,000 suspected cases and 511 deaths were reported in 2023 alone, escalating to 17,541 cases and 517 deaths by late 2024.^[117] ^[118] In contrast, West African outbreaks, such as Nigeria's since 2017, involve fewer cases annually, often under 100 confirmed, with sporadic zoonotic introductions. Endemic foci span multiple countries, including the DRC, Republic of the Congo, Central African Republic, Cameroon, Nigeria, Sierra Leone, and Liberia, though the DRC accounts for 80-90% of continental cases historically.^[119] ^[120] Pediatric cases predominate in endemic settings, reflecting household exposure and lower prior immunity post-smallpox eradication, with CFR declining with age.^[121] Recent genomic shifts, including Clade Ib emergence in the DRC since 2023, have amplified human-to-human chains in urban areas, deviating from traditional zoonotic patterns but rooted in longstanding endemicity.^[122] Underreporting remains prevalent due to surveillance gaps, with confirmed cases historically representing only 36-76% of suspects in the DRC.^[123]

Pre-2022 outbreaks

The first human case of monkeypox was reported on September 1, 1970, in a nine-month-old boy in the Democratic Republic of the Congo (DRC), with subsequent sporadic cases emerging in the region through laboratory confirmation via electron microscopy and serology.^[40] Between 1970 and 1999, approximately 400 cases were documented across Central Africa, primarily clade I infections linked to bushmeat handling and rodent reservoirs, with case-fatality ratios estimated at 10-15% in unvaccinated children.^[124] The largest pre-2022 outbreak outside Africa occurred in the United States from May to July 2003, involving 71 confirmed or probable cases across six Midwestern states (Illinois, Indiana, Kansas, Missouri, Ohio, and Wisconsin), all associated with exposure to pet prairie dogs infected by imported Gambian giant rats from Ghana.^[125] No human deaths resulted, and symptoms were generally mild, with limited secondary transmission (only two generations observed); genomic analysis confirmed the West African clade (clade IIb), highlighting risks from exotic pet trade rather than sustained human spread.^[126] In West Africa, monkeypox re-emerged prominently in Nigeria starting September 2017 after a 39-year absence of reported cases, with 276 suspected infections across 26 of 36 states by September 2018, including 118 laboratory-confirmed cases and four probable deaths (case-fatality ratio ~3.4%).30294-4/fulltext) This outbreak, the largest for the West African clade to date, involved urban-rural spread, with 88% of confirmed cases male and median age 32 years; phylogenetic evidence pointed to multiple zoonotic spillovers from rodents, compounded by declining smallpox vaccination immunity.^[127] By 2019, Nigeria reported over 200 suspected cases annually, with seven fatalities, underscoring endemic potential beyond Central Africa.^[128] This Nigerian resurgence facilitated limited exportations to non-endemic countries, including three cases in the United Kingdom (2018-2019, one fatal), single travel-related cases in Israel, Singapore, and the United Kingdom in 2018, and a U.S. case in Dallas, Texas, in July 2021 from a traveler returning from Nigeria.^[129] Between September 2018 and June 2021, six such imported cases from Nigeria were documented globally, all clade IIb, with no secondary chains exceeding household contacts, reflecting low transmissibility outside high-risk exposures.^[130] Smaller clusters occurred in Central African Republic (2015-2016, ~20 cases) and other endemic nations, but remained contained without international spread.^[119] Overall, pre-2022 outbreaks totaled fewer than 500 confirmed cases outside Africa, contrasting with thousands annually in DRC, where clade I drove persistent circulation.^[131]

2022 global outbreak

The 2022 global outbreak of mpox (monkeypox) originated from cases imported from endemic regions in Africa, with the first detection in a non-endemic country occurring on May 6, 2022, when the United Kingdom confirmed a case in a traveler returning from Nigeria.^[132] This marked the onset of widespread human-to-human transmission outside traditional reservoirs, involving the less virulent clade IIb (formerly West African clade) of the monkeypox virus, which has a historical case fatality rate of approximately 1% compared to 10% for clade I.^[40] ^[133] By May 21, 2022, 92 laboratory-confirmed cases had been reported across 12 non-endemic countries in Europe, North America, and Israel, with no deaths at that point.^[134] Transmission during the outbreak was predominantly through prolonged close physical contact, including sexual activity, rather than sustained respiratory spread, distinguishing it from prior aerosol-associated patterns in some animal models.^[134] The majority of cases—over 95% in initial analyses—occurred among men who have sex with men (MSM), often linked to sexual networks involving multiple partners, such as at large gatherings or venues like saunas.^[135] ^[136] Limited secondary transmission to household contacts or non-MSM individuals was documented, but chains did not sustain in the general population, reflecting the virus's reliance on specific behavioral risk factors for propagation.^[137] Case numbers surged in June 2022, exceeding 1,500 confirmed infections across 43 countries by June 10, with Europe reporting the highest burden.^[137] The World Health Organization (WHO) declared a Public Health Emergency of International Concern (PHEIC) on July 23, 2022, amid over 16,000 cases and 5 deaths globally by that date.^[40] By the outbreak's peak in August 2022, weekly global cases reached approximately 1,000, concentrated in the United States (over 26,000 cases from May to October) and European nations like the UK, Germany, and France.^[138] Cumulative figures surpassed 80,000 laboratory-confirmed cases by December 2022, spanning more than 100 countries, with deaths totaling around 100 outside Africa—yielding a clade IIb case fatality rate under 1% in well-resourced settings, though higher in regions with comorbidities like advanced HIV.^[40] ^[139] The outbreak waned by late 2022 due to targeted vaccination campaigns using the Jynneos vaccine (prioritized for at-risk MSM groups), antiviral deployment like tecovirimat, and behavioral adaptations within affected communities, leading WHO to lift the PHEIC on May 11, 2023, after cases dropped below 100 weekly globally.^[140] Genomic sequencing confirmed a single B.1 lineage spillover from the 2018-2019 Nigeria outbreak, with mutations enhancing transmissibility via skin lesions but not altering core zoonotic or vector-independent dynamics.^[40] No evidence supported broad airborne or fomite-driven community spread as primary drivers, aligning with empirical contact-tracing data emphasizing intimate exposure.^[134]

2024-2025 resurgence and global cases

A resurgence of monkeypox occurred in 2024, primarily affecting Central and Eastern Africa, where clade I monkeypox virus, particularly the sublineage Ib, drove increased transmission through community and household contacts.^[140] The Democratic Republic of the Congo reported the majority of cases, with the outbreak spreading to neighboring countries including Burundi, Rwanda, Uganda, and Kenya.^[56] This wave contrasted with the 2022 global outbreak, which was predominantly clade IIb and linked to sexual transmission networks outside endemic areas.^[140] The World Health Organization declared the clade I outbreak a public health emergency of international concern on August 14, 2024, citing over 40,000 suspected and confirmed cases in Africa since January 2024, alongside a case fatality rate exceeding 3% in some regions.^[140]^[56] By late 2024, more than 50,000 suspected cases and approximately 1,000 deaths had been recorded across Africa, surpassing previous annual totals.^[141] Interventions including vaccination campaigns and enhanced surveillance contributed to a decline in cases during 2025, with weekly confirmed cases dropping by 52% in certain periods and overall reductions of 28% between June and July.^[142]^[143] The emergency status was lifted on September 5, 2025, as transmission waned, though vigilance was urged due to ongoing risks in 13 African countries with sustained activity.^[144]^[56] Globally, clade I cases remained largely confined to Africa, with 23 countries reporting travel-associated infections but no evidence of widespread community spread.^[56] In the United States, only nine clade I cases were documented by October 2025—six travel-related and three non-travel—assessed as posing low risk to the general population.^[56] Clade II monkeypox persisted at low levels worldwide, with sporadic upticks tied to West African endemic circulation.^[56]

Prevention, treatment, and control

Vaccination strategies and efficacy

The primary vaccines deployed against monkeypox virus infection are JYNNEOS (also known as MVA-BN, Imvamune, or Imvanex), a non-replicating modified vaccinia Ankara vaccine, and ACAM2000, a replication-competent vaccinia virus vaccine originally developed for smallpox. JYNNEOS is preferentially recommended due to its safer profile, lacking the risks of myocarditis, pericarditis, and uncontrolled replication associated with ACAM2000, particularly in individuals with HIV or skin conditions. ACAM2000 provides cross-protection inferred from historical smallpox vaccination data, with 1980s African studies indicating approximately 85% efficacy against monkeypox among prior smallpox vaccinees, though real-world human data for modern outbreaks remain limited. Animal models, including cynomolgus macaques challenged with monkeypox virus, demonstrate robust protection from both vaccines against lethal doses, with ACAM2000 showing complete survival in some trials despite minor rashes in outliers.^[145]^[146]^[147] Vaccination strategies emphasize targeted pre-exposure prophylaxis (PrEP) rather than mass campaigns, focusing on high-risk populations such as men who have sex with men (MSM) with multiple partners, close contacts of cases, healthcare workers handling specimens, and laboratory personnel. In the 2022 global outbreak, the U.S. CDC and WHO endorsed JYNNEOS PrEP with two subcutaneous doses administered 28 days apart for at-risk adults aged 18 years and older, alongside post-exposure prophylaxis (PEP) using a single dose within 4-14 days of exposure to mitigate progression. Initial supply constraints led to intradermal dosing protocols to stretch doses fivefold, maintaining comparable immunogenicity in trials. By late 2022, over 1 million JYNNEOS doses were administered globally, primarily in outbreak epicenters like Europe and North America, correlating with declining incidence in vaccinated cohorts. For the 2024-2025 resurgence, particularly clade I cases in Africa, strategies shifted toward equity-focused distribution, though vaccine access remained limited, with fewer than 500,000 doses pledged to endemic regions by mid-2025.^[148]^[149]^[150] Efficacy data for JYNNEOS derive largely from observational studies during the 2022 clade II outbreak, with three case-control analyses estimating vaccine effectiveness (VE) at 66-89% against symptomatic disease following two doses, and 35-75% after one dose, based on reduced odds of infection among vaccinated MSM. A pooled analysis of six studies reported breakthrough infection rates of 2.19% (range 0.37-5.32%) post-vaccination, indicating incomplete sterilizing immunity but substantial attenuation of severe outcomes, including hospitalization odds reduced by over 50%. Single-dose VE reached 76% (95% CI 59-86%) in U.K. cohorts, underscoring partial protection during the interval before the second dose. ACAM2000's human efficacy against monkeypox lacks direct randomized data but aligns with vaccinia cross-reactivity, offering near-complete protection in primate challenges against outbreak strains. Limitations include reliance on clade II observational evidence, potential immortal time bias in PEP estimates, and sparse data for clade I, where vaccines attenuate disease but efficacy may vary due to antigenic differences. Ongoing trials, such as those evaluating LC16m8 (another attenuated vaccinia), report inferred 85-90% clinical efficacy against both clades, though full results remain pending as of 2025.^[150]^[151]^[152]

Antiviral therapies

Tecovirimat, also known as TPOXX or ST-246, is an antiviral agent originally developed and FDA-approved for smallpox treatment under the Animal Rule, based on efficacy in non-human primate models of orthopoxvirus infection.^[153] For monkeypox, it has been administered under expanded access protocols, particularly during the 2022 outbreak and subsequent resurgences, targeting severe cases, immunocompromised patients, or those with complications like ocular involvement.^[154] In vitro and animal studies demonstrate inhibition of viral envelope formation by targeting the VP37 protein, reducing mortality in lethal challenge models.^[155] However, randomized controlled trials, such as the STOMP study (NCT05534984), enrolling over 500 participants with confirmed mpox, found tecovirimat safe with minimal adverse effects but no significant reduction in time to lesion resolution compared to placebo, as most cases were mild and self-limiting.^[156] ^[157] This lack of demonstrated clinical benefit in humans has prevented FDA approval for monkeypox specifically, despite compassionate use reports of symptom improvement in select patients.^[158] ^[159] Cidofovir and its prodrug brincidofovir (Tembexa) represent additional options with activity against orthopoxviruses, approved by the FDA for cytomegalovirus retinitis (cidofovir) and smallpox preparedness (brincidofovir).^[154] These nucleotide analogs inhibit viral DNA polymerase, showing potent reduction of monkeypox viral replication in cell cultures and respiratory tract models of clade II strains.^[160] Brincidofovir, with improved oral bioavailability and reduced nephrotoxicity compared to cidofovir, has been stockpiled for orthopoxvirus threats but exhibits uncertain efficacy in mpox human cases, with reports of treatment discontinuation due to elevated liver enzymes.^[161] ^[162] Limited observational data from the 2022 outbreak suggest potential utility in severe or disseminated disease, but no large-scale randomized trials confirm accelerated recovery or mortality benefits, and their use is reserved for patients failing supportive care due to toxicity risks.^[163] Overall, antiviral therapies for monkeypox remain investigational for routine use, with supportive measures like pain management and wound care constituting the mainstay for most infections, which resolve without intervention in immunocompetent individuals.^[164] Ongoing trials as of 2025 explore combinations or novel agents like NV387 to address gaps in efficacy against emerging clades, but empirical evidence underscores that antivirals' causal impact on outcomes is modest in mild presentations predominant in global outbreaks.^[158] ^[165] Prioritization for high-risk groups reflects this, informed by preclinical data rather than robust human endpoints.^[94]

Non-pharmaceutical interventions

Isolation of confirmed or suspected monkeypox cases remains a cornerstone of outbreak control, with guidelines recommending that individuals remain at home or in a designated location until all lesions have crusted, scabs have fallen off, and a fresh layer of skin has formed, typically 2-4 weeks after symptom onset.^[166] This measure interrupts direct contact and fomite transmission, as the virus spreads primarily through skin-to-skin contact with lesions, respiratory droplets during prolonged face-to-face interactions, or contaminated materials.^[40] During the 2022 global outbreak, prompt isolation reduced secondary transmission rates, with modeling indicating that adherence to isolation protocols could prevent resurgence by limiting community spread.^[167] Contact tracing, combined with quarantine of exposed individuals, facilitates early detection and containment. Public health authorities conduct interviews to identify high-risk contacts—those with direct skin-to-skin or intimate contact—and recommend quarantine for 21 days, monitoring for symptoms without routine testing unless ill.^[168] ^[169] In the 2022 outbreak, these strategies, alongside vaccination, blunted exponential growth, particularly in high-incidence networks, though challenges arose from underreporting and asymptomatic spread.^[170] Effectiveness depends on rapid implementation; delays in tracing extended chains of transmission in urban settings.^[171] In healthcare and community settings, infection prevention relies on contact and droplet precautions, including gloves, gowns, eye protection, and N95 respirators for aerosol-generating procedures.^[172] Hand hygiene with soap and water or alcohol-based sanitizers, alongside disinfection of surfaces, mitigates fomite risks, as the virus can persist on objects.^[173] Behavioral measures, such as avoiding close physical contact, sharing bedding, or participation in high-risk social events, proved effective in reducing incidence during the 2022-2023 period, with empirical data showing a 38% overall drop in cases attributable to layered NPIs in controlled environments.^[174] ^[175] For the 2024-2025 resurgence, particularly clade Ib in Africa and exported cases, sustained NPIs are emphasized to avert wider dissemination, as modeling underscores isolation's role in curbing potential urban outbreaks where vaccination coverage lags.^[176] Surveillance integration enhances these interventions by enabling proactive ring strategies around cases.^[177]

Controversies and public health debates

Risk behaviors and transmission realities

Monkeypox virus spreads primarily through prolonged close physical contact with infectious skin lesions, bodily fluids, respiratory secretions, or contaminated objects, rather than casual or airborne transmission over distances.^[40] In the 2022 global outbreak of clade IIb, sexual contact emerged as the dominant mode, accounting for approximately 69% of reported transmissions across analyzed cases, with chains sustained in networks characterized by high partner turnover.00198-5/fulltext) Evidence from genomic sequencing and contact tracing indicates introduction into densely connected sexual networks among men who have sex with men (MSM) around late April 2022 in Europe, facilitating rapid dissemination through intimate skin-to-skin and mucosal exposures during sexual activities.^[178] Key risk behaviors amplifying transmission include multiple concurrent sexual partners, attendance at events involving group intimate contact such as sex-on-premises venues, and delayed recognition of prodromal symptoms like rash or lesions during infectious periods.^[179] In early outbreak cohorts, over 98% of confirmed cases in regions like the UK and Spain were among MSM, with median partner counts exceeding typical population levels, underscoring how behavioral patterns in these subgroups drove exponential growth absent in broader demographics.00411-X/fulltext) ^[180] Zoonotic risks persist in endemic African regions through handling of infected rodents or primates, but human-to-human chains outside sexual contexts remain limited, with household secondary attack rates below 10% even among close contacts without intimate exposure.^[81] Transmission realities reveal a basic reproduction number (R0) estimated at 1.4 to 2.4 for the 2022 MSM-focused epidemic, far below highly contagious respiratory viruses and insufficient for uncontrolled spread in the general population without repeated high-risk exposures.^[181] ^[182] Presymptomatic shedding occurs but contributes minimally compared to lesion contact, and no sustained community transmission has been documented beyond behaviorally linked clusters, contrasting initial public health alerts framing it as a broad pandemic threat.^[183] This concentration in specific risk groups—evident from over 99% male cases in non-endemic settings during peak months—highlights causal links to intimate contact practices rather than inherent viral volatility, informing targeted interventions over generalized measures.^[45] Debates arise over emphasizing these behavioral realities versus broader stigma concerns, with some analyses attributing outbreak control to risk reduction in affected networks rather than universal restrictions.^[184]

Media portrayal and overhyping threats

During the 2022 global outbreak, mainstream media outlets frequently framed monkeypox as a burgeoning pandemic threat, with headlines evoking comparisons to more lethal viruses like smallpox and warnings of uncontrolled spread beyond initial clusters. For instance, coverage highlighted the World Health Organization's declaration of a Public Health Emergency of International Concern on July 23, 2022, after approximately 18,000 confirmed cases across 70 countries, amplifying fears of exponential growth similar to COVID-19. However, empirical data revealed a case fatality rate (CFR) of less than 0.2% for the predominant clade IIb strain in non-endemic regions, with most infections presenting as mild and self-limiting, confined largely to sexual networks among men who have sex with men (MSM).^[185] ^[186] This portrayal contrasted sharply with the virus's transmission dynamics, which required prolonged close contact—primarily skin-to-skin during intimate activities—limiting broader community spread. U.S. cases peaked at around 400 per day in August 2022 before declining without widespread lockdowns or general population measures, totaling about 30,000 infections and 42 deaths by mid-2023, yielding a CFR of approximately 0.14%.^[187] A White House official noted in May 2022 that domestic cases remained in the "very low single digits," underscoring minimal public risk outside high-exposure groups.^[188] Critics, including public health analysts, contended that such media emphasis on worst-case scenarios overlooked these realities, potentially driven by institutional incentives for heightened vigilance post-COVID, though peer-reviewed analyses confirmed the outbreak's controllability via targeted interventions rather than mass panic.^[189] Social media and public discourse reflected skepticism toward media narratives, with thematic analyses of Twitter posts identifying "monkeypox doubts and media" as prominent themes, comprising 22% of sampled content, often questioning the proportionality of alarm relative to the virus's historical 1-3% CFR in vaccinated or accessible-care settings.^[190] In non-endemic areas, a 2022 multi-country study reported hospitalization rates below 10% and no deaths among 528 cases, further evidencing overstatement of severity in early reporting.^[89] While credible sources like the CDC emphasized accurate risk stratification, mainstream outlets' initial focus on exotic origins and potential mutations—despite genomic stability in clade IIb—contributed to transient resource diversions, though subsequent data validated the threat's containment without justifying the initial hype.^[56] The 2024-2025 resurgence, driven by clade Ib in Africa with a higher CFR of 3-6%, renewed some coverage, but global cases remained under 100,000 cumulative with 200-300 deaths, prompting questions of selective amplification in Western media compared to endemic realities.^[134] ^[191] This pattern aligns with observations of media tendencies to prioritize novel threats over baseline epidemiology, potentially influenced by systemic biases favoring dramatic narratives in public health reporting from institutions with histories of alarmist projections.^[192] Empirical tracking by bodies like the WHO confirmed no sustained pandemic trajectory, reinforcing that portrayals often exceeded verifiable risks.^[134]

Response policies and resource allocation biases

The World Health Organization's declaration of a Public Health Emergency of International Concern for mpox on July 23, 2022, facilitated vaccine procurement and distribution, yet global resource allocation disproportionately benefited high-income countries experiencing the clade IIb outbreak, while endemic African nations received minimal support.^[193] By late 2022, over 80% of available Jynneos (MVA-BN) vaccine doses were administered in Europe and North America, despite Africa's historical burden of cases exceeding 15,000 annually in prior decades.^[194] This pattern echoed COVID-19 vaccine nationalism, where production and stockpiling prioritized Western markets, leaving low-income regions with under 1% of global supplies amid diagnostic and treatment gaps.^[195]^[196] In the United States, the Department of Health and Human Services declared a public health emergency on August 4, 2022, enabling expanded vaccine access, but initial rollout exhibited demographic biases, with early events in areas like Fulton County, Georgia, administering doses preferentially to White individuals despite Black and Hispanic communities comprising over 70% of cases.^[197]^[198] By mid-2023, vaccination series completion rates showed persistent disparities, with Black recipients at 35% lower odds of completing the two-dose regimen compared to White recipients, attributable to barriers in outreach and eligibility prioritization favoring urban, higher-access groups.^[199] These inequities stemmed from policies emphasizing broad eligibility over targeted, behavior-based risk stratification, despite data indicating over 95% of U.S. cases linked to sexual networks among men who have sex with men.^[200] The 2024-2025 resurgence of clade I mpox in Central and West Africa exposed deepened allocation failures, as international pledges for vaccine donations—totaling under 500,000 doses by early 2025—covered less than 2% of at-risk populations in countries like the Democratic Republic of the Congo, where over 25,000 suspected cases and 1,200 deaths were reported by October 2025.^[201]^[202] The Africa Centers for Disease Control and Prevention's continental emergency declaration on August 4, 2024, and WHO's subsequent PHEIC renewal highlighted neglect of surveillance infrastructure in low-resource settings, with underreporting masking true incidence and diverting aid from empirical hotspots.^[203]^[204] Policy responses, including temporary WHO recommendations for prioritized sharing, faltered due to manufacturing constraints in high-income nations and hesitancy in deploying older ACAM2000 vaccines amid side-effect concerns, resulting in case-fatality rates up to 10% in unvaccinated African cohorts versus under 0.1% in vaccinated Western ones.^[205]^[206] Such disparities reflect causal priorities in global health funding, where outbreak visibility in affluent regions drives resource flows over sustained investment in endemic prevention.^[207]

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Nov 16, 2023 · MPXV is a type of enveloped Orthopoxvirus. It has a double-stranded genome of 197 kb encoding more than 200 proteins [4]. The previously endemic ...
[14]
Monkeypoxvirus genome - ViralZone
The poxvirus genome is about 200kb in size and encodes about 200 proteins. It is a linear double-stranded DNA genome with covalently closed hairpin ends.
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Mpox (formerly monkeypox): pathogenesis, prevention and treatment
Dec 27, 2023 · The genomic structure of Mpox virus closely resembles that of other orthopoxviruses, characterized by a highly conserved central core region, ...
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Comparative genome analysis reveals driving forces behind ...
A comparative analysis of 404 Monkeypox virus (MPXV) genomes revealed notable changes in microsatellite abundance and density, especially within Clades I, IIa, ...Missing: peer- | Show results with:peer-<|separator|>
[17]
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Apr 18, 2024 · We determine a high-quality MPXV genome sequence of a representative of the current epidemic with LCRs resolved at unprecedented accuracy.
[18]
An overview on monkeypox virus: Pathogenesis, transmission, host ...
Feb 10, 2023 · For replication, MV initially uncoats to gain entry into the cytoplasm (Sklenovská, 2020). The early genes are then expressed after the ...
[19]
Structure of monkeypox virus DNA polymerase holoenzyme - Science
Dec 15, 2022 · A rolling cycle mechanism has been proposed to replicate DNA in the form of unbranched head-to-tail concatemers, which would be resolved by a ...
[20]
WHO recommends new name for monkeypox disease
Nov 28, 2022 · Consensus was reached to refer to the former Congo Basin (Central African) clade as Clade one (I) and the former West African clade as Clade two ...
[21]
Geographic Structuring and Divergence Time Frame of Monkeypox ...
We show that the population transmitted in West Africa (clades 2/3) experienced limited drift. Conversely, clade 1 (transmitted in the Congo Basin) possibly ...
[22]
Virulence differences of mpox (monkeypox) virus clades I, IIa, and IIb ...
Feb 14, 2023 · Three clades of mpox (monkeypox) virus are recognized: Clade I is present in the Congo Basin, causes up to 10% human mortality, and is transmitted by rodents ...Clade I Mpxv And Clade Iia... · Clade I Mpxv Is Up To 1,000... · Mpxv Clade Iib Is More...
[23]
Sustained human outbreak of a new MPXV clade I lineage ... - Nature
Jun 13, 2024 · Here we describe the epidemiological and genomic features of an mpox outbreak in a mining region in eastern Democratic Republic of the Congo, caused by clade I ...
[24]
Mpox – African Region - World Health Organization (WHO)
Aug 22, 2024 · Mpox is an infectious disease caused by the monkeypox virus (MPXV). There are two known clades of MPXV: clade I, previously called the Congo ...
[25]
Concurrent Clade I and Clade II Monkeypox Virus Circulation ... - CDC
Feb 7, 2024 · Phylogenetic studies report 2 distinct MPXV clades: clade I, prevalent in Central Africa, and clade II, endemic to West Africa (5,6,26–28).
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Aug 4, 2025 · Clades Ia and IIa, primarily circulating in Equatorial Africa, generally cause zoonotic spillovers, whereas specific lineages of clades Ib and ...
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[PDF] Mpox Virus: Clade I and Clade II
Aug 7, 2024 · The monkeypox (mpox) virus—a serious viral zoonosis endemic in west and central Africa—is classi ed into 2 main clades, clade I and clade ...
[28]
Emergence of Clade Ib Monkeypox Virus—Current State of Evidence
Jul 23, 2025 · Monkeypox virus (MPXV), the causative agent of mpox, has been maintained in animal reservoirs in the forested regions of West and Central Africa ...
[29]
Global genomic surveillance of monkeypox virus | Nature Medicine
Oct 23, 2024 · In 2022, mpox epidemiology shifted with the emergence of a new lineage—clade IIb—that spread worldwide through human-to-human transmission, and ...
[30]
Update of the Genetic Variability of Monkeypox Virus Clade IIb ...
Sep 11, 2024 · Clade II was identified during outbreaks in Nigeria, Singapore, the United Kingdom, and the United States between 2017 and 2019 and is ...
[31]
Virulence differences of mpox (monkeypox) virus clades I, IIa, and IIb ...
Feb 14, 2023 · Three clades of mpox (monkeypox) virus are recognized: Clade I is present in the Congo Basin, causes up to 10% human mortality, and is transmitted by rodents ...
[32]
Genomic epidemiology of mpox virus during the 2022 outbreak in ...
Sep 24, 2025 · The genomic diversity of MPXV is represented in two clades, I and II. Clade I further subdivided into Clade Ia and newly identified Clade Ib.
[33]
Understanding the evolutionary dynamics of Monkeypox virus ...
Jul 16, 2025 · Monkeypox virus (MPXV) species in the genus Orthopoxvirus, Poxviridae family, includes two major clades, the formerly Congo Basin (clade I) and ...
[34]
[PDF] Genomic analyses of recently emerging clades of mpox virus reveal ...
Sep 25, 2024 · Extragenic Mutations Predominate Across All MPXV Clades lowest mutation count with an average of 300, and Clade Ib shows 329 mutations on ...
[35]
Clade I mpox virus genomic diversity in the Democratic Republic of ...
Jan 9, 2025 · Real-time PCR assays for the specific detection of monkeypox virus West African and Congo Basin strain DNA. J. Virol. Methods, 169 (2010), pp ...
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The emergence of a novel mpox virus strain (clade Ib) in Central Africa
These mutations in clade Ib contribute to its increased virulence, replication efficiency, and potential drug resistance, highlighting the higher public health ...Missing: characteristics | Show results with:characteristics
[37]
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The MPXV, the etiological agent, is a part of the Orthopoxvirus genus within the Poxviridae family and is native to West and Central Africa (Alakunle et al., ...
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Emerging variants of Mpox virus and tecovirimat resistance
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Phylogenetic and Molecular Evolutionary Insights into Monkeypox ...
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Review of Evidence Related to the Zoonotic Characteristics of the ...
Oct 15, 2024 · A Review of Evidence Related to the Zoonotic Characteristics of the Monkeypox Virus Open Access ... Mpox had spread from rodents imported from ...Missing: origins | Show results with:origins
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A review of experimental and natural infections of animals with ...
Monkeypox virus (MPXV) has a broad host-range and is capable of infecting many species from across the globe. In nature, the major environs of MPXV are ...
[43]
Human monkeypox: history, presentations, transmission ...
Jul 20, 2023 · The monkeypox virus mostly infects wild rodents in the rainforests of Central and West Africa, with infection likely resulting from direct ...
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Oct 1, 2020 · Since identification of the first human case of monkeypox in 1970 in the Democratic Republic of the Congo (then known as Zaire) in a 9-month ...<|control11|><|separator|>
[45]
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The monkeypox virus is a large, enveloped virus (Panel A, right). Each virion encapsulates a core that contains a linear, double-stranded DNA (dsDNA) genome of ...
[46]
No evidence of mpox virus circulation in putative animal reservoirs ...
Jun 13, 2024 · However, the natural reservoir of the virus remains elusive. In this study, we looked for potential reservoirs of the mpox virus (MPXV) in ...
[47]
Geographic Structuring and Divergence Time Frame of Monkeypox ...
Depending on the model used, we estimated that the 2 clades separated ∼560–860 (highest posterior density: 450–960) years ago, a period characterized by ...Missing: peer- | Show results with:peer-
[48]
Phylogenetic Analysis of the Mpox Virus in Sub-Saharan Africa ...
Jun 26, 2025 · Phylogenetic analysis of 270 curated MPXV sequences from Sub-Saharan Africa identified two major clades: Clade I (Ia, Ib) and Clade II (IIa, IIb) ...
[49]
Phylogenomic characterization and signs of microevolution in the ...
Jun 24, 2022 · In this study, shotgun metagenomics allowed the rapid reconstruction and phylogenomic characterization of the first MPXV outbreak genome sequences.
[50]
Multiple lineages of monkeypox virus detected in the United States ...
Oct 20, 2022 · We identified two lineages of monkeypox virus (MPXV) among two 2021 and seven 2022 US monkeypox cases: the major 2022 outbreak variant called B.1 and a minor ...
[51]
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Jan 17, 2023 · Phylogenetic analysis of monkeypox virus genomes showed statistically significant divergence and nascent subclades during the 2022 mpox outbreak ...<|separator|>
[52]
Selective events at individual sites underlie the evolution of ...
May 20, 2023 · We applied a population genetics—phylogenetics approach to investigate the evolution of MPXV during historical viral spread in Africa and to ...Missing: peer- | Show results with:peer-
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Monkeypox virus: a neglected zoonotic pathogen spreads globally
Jul 20, 2022 · Monkeypox virus (MPXV), a DNA virus, is the aetiological agent of a zoonotic disease known as monkeypox (MPX) and is grouped into two genetic ...Missing: origins | Show results with:origins
[54]
An animal source of mpox emerges — and it's a squirrel - Nature
the animals that carry and spread the virus ...
[55]
Monkeypox Virus in Animals: Current Knowledge of Viral ...
Mar 31, 2023 · Monkeypox virus (MPXV) is a complex cytoplasmic double-stranded DNA virus, belonging to the genus Orthopoxvirus (OPXV), family Poxviridae [1,2].
[56]
Monkeypox in the United States and Around the World - CDC
Oct 17, 2025 · There are two types of the virus that causes monkeypox, clade I and clade II. Both types spread the same way and can be prevented using the same ...
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[PDF] Investigating Monkeypox in the Wild
In Africa, monkeypox is endemic, outbreaks occur sporadically, and human-to-human transmission of the virus is documented. No reliable evidence exists to ...
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Although monkeypox virus has been isolated from several rodents and non-primate animals in Africa (eg, rope squirrels, tree squirrels, Gambian rats, dormice ...<|separator|>
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Monkeypox has a similar but less severe disease presentation than smallpox (Simpson et al., 2020). Clinically, three distinct phases - incubation, prodrome, and ...
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No evidence of mpox virus circulation in putative animal reservoirs ...
No MPXV DNA was detected despite the presence of potential host reservoirs such as Critcetomys, Crocidura, Praomys, and Atherurus africanus.
[61]
long-term monitoring and analysis of zoonosis is crucial to confirm ...
A schematic diagram illustrates general concepts of the monkeypox virus's zoonosis and its spillover event from the natural reservoir to intermediate hosts.
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Human monkeypox: history, presentations, transmission ... - Frontiers
Monkeypox transmission can occur through contact with body fluids, skin lesions, virus-containing waste, respiratory droplets from infected animals, and ...
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Temporal and age-structured analysis of Mpox spread in the 2022 ...
Oct 9, 2025 · In the 2022 outbreak of mpox, sexual contact has become the main route of transmission. According to data from WHO [3], among 18,980 cases ...
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Mpox in UK households: estimating secondary attack rates and ...
Oct 2, 2024 · The secondary attack rate among UK household mpox contacts was 4% (60/1 526). Sexual contact with the index case was associated with a 11 ...
[66]
Human monkeypox: secondary attack rates - PMC - NIH
The highest attack rate (11.7%) occurred among unvaccinated household contacts in the age group 0-4 years. However, the majority of susceptible persons who ...
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Mpox in UK households: estimating secondary attack rates and ...
Oct 2, 2024 · Sixty-two household contacts were known to subsequently become a case of mpox, an overall secondary attack rate of 4% to UK household contacts.
[68]
[PDF] Master Question List for Monkeypox Virus (MPXV)
Oct 10, 2024 · The R0 of mpox across all clades is generally estimated to be between 0.57 to a maximum of 1.25. The calculated R0 for the Clade IIb outbreak ...
[69]
Transmission dynamics and effect of control measures on the 2022 ...
The mpox outbreak in England probably resulted from high sexual partner rates among some GBMSM, with reductions in partner rates reversing the outbreak.
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Review The recent re-emergence of human monkeypox
The further spread of the monkeypox virus in the human population is because of subsequent human-to-human transmission event, which occurs via close contact ...
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Human monkeypox virus: An updated review - Medicine
Sep 2, 2022 · It is believed that the virus is transmitted through respiratory secretions and saliva, or through direct contact with the exudate or crust ...2. Methods · 2.1. Main Text · 2.1. 3. Clinical Picture
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Mpox virus: virology, molecular epidemiology, and global public ...
Jul 16, 2025 · Human-to-human transmission primarily happens through contact with lesions, scabs, saliva, or other bodily fluids from infected individuals, as ...
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Squirrel reservoirs of monkeypox virus are sister species separated ...
Monkeypox is an emerging infectious disease of unclear zoonotic origin in Africa ... monkeypox virus (MPXV). Here, we describe new data on the systematics of ...
[74]
The potential risks posed by inter- and intraspecies transmissions of ...
There are currently no known animal reservoirs for MPXV outside of Africa; however, during the 2003 outbreak of MPXV in pet prairie dogs in America, there was ...Missing: interspecies | Show results with:interspecies
[75]
No evidence of mpox virus circulation in putative animal reservoirs ...
Jun 13, 2024 · Our study did not allow the identification of MPXV host reservoirs in Gabonese wildlife despite the significant number of samples and the ...Missing: interspecies | Show results with:interspecies
[76]
Plausible reasons for the resurgence of Mpox (formerly Monkeypox)
Dec 25, 2023 · Living in forested or recently deforested areas, not receiving a smallpox vaccination, handling or consuming dead bush meat or monkeys, and ...<|separator|>
[77]
Mapping global zoonotic niche and interregional transmission risk of ...
Aug 17, 2023 · This climatic-driven zoonotic spillover potentially generated by human activities such as deforestation, combined with agricultural activities ...
[78]
Climatic determinants of monkeypox transmission: A multi-national ...
Environmental factors such as temperature and rainfall have frequently been shown to significantly influence infectious diseases (Koelle et al., 2005) 13.
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Stability of Monkeypox Virus on Commonly Contacted Surfaces in ...
Apr 16, 2025 · We show that MPXV stability is influenced by both surface type and temperature, with nonporous surfaces and lower temperatures supporting longer virus ...
[80]
Environmental Persistence of Monkeypox Virus on Surfaces ... - CDC
Oct 10, 2022 · These findings indicate that porous surfaces (e.g., bedding, clothing) may pose more of a MPXV exposure risk than nonporous surfaces (e.g., ...
[81]
Factsheet for health professionals on mpox - ECDC
The monkeypox virus (Orthopoxvirus monkeypox) is an enveloped virus with a ... In cases in endemic areas (Africa), a centrifugal maculopapular rash ...
[82]
Understanding mpox pathogenesis: therapeutic potential of marine ...
MPXV initiates infection by binding to host cell surface molecules such as glycosaminoglycans (heparan sulfate, chondroitin sulfate) and integrins via viral ...
[83]
Exploring monkeypox virus proteins and rapid detection techniques
May 27, 2024 · As with other poxviruses, MPXV replication occurs in the cytoplasm and undergoes through virally encoded RNA polymerase. As depicted in Figure ...
[84]
Monkeypox: disease epidemiology, host immunity and clinical ...
Sep 5, 2022 · In this Review, we discuss the clinical, epidemiological and immunological features of MPXV infections. We also highlight important research questions.
[85]
Monkeypox Virus: A Comprehensive Overview of Viral Pathology ...
Aug 9, 2023 · These viruses share the same process of infection, which is confirmed by similar genes and encoded proteins that interfere with host cell ...
[86]
Pathogenesis of the circulating mpox virus and its adaptation to ...
Mar 20, 2023 · The disease is caused by mpox virus (MPXV), a virus endemic in an animal reservoir in the sub-Saharan Africa (Fig. 1). MPXV transmits ...<|separator|>
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Mpox Clinical Presentation, Diagnostic Approaches, and Treatment ...
Oct 14, 2024 · This review examines the epidemiology, transmission, clinical presentation, assessment and diagnosis, prognosis, management and treatment, ...
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Clinical Characteristics of Human Mpox (Monkeypox) in 2022
In this review, fever, lymphadenopathy, fatigue, and malaise or asthenia were the most common accompanying symptoms. Lesions on the limbs were the most common ...
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Monkeypox Virus Infection in Humans across 16 Countries
Jul 21, 2022 · There is no clear evidence of sexual transmission through seminal or vaginal fluids. Vertical transmission and fetal deaths have been described.<|control11|><|separator|>
[90]
Clinical characteristics and predictors of human mpox outcome ...
Aug 22, 2023 · About 40% to 50% of people with mpox during the 2022 global outbreak were people with HIV, most of whom presented with localised anogenital skin ...
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Comparative analysis of Mpox clades: epidemiology, transmission ...
Oct 13, 2025 · Clade I and Clade II of Mpox (monkeypox) are distinct genetic lineages of the virus (Fig. 1). Clade I, primarily found in Central Africa, has a ...
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Severe Monkeypox in Hospitalized Patients — United States, August ...
Nov 4, 2022 · Twelve patients died, and monkeypox was a cause of death or contributing factor in five patients to date, with several other deaths still under ...
[93]
Epidemiology, clinical manifestations, and diagnosis of mpox ...
During the outbreak that started in 2022, patients with mpox have presented with proctitis or tonsillitis. ○Proctitis – ...
[94]
Mpox 2022 to 2025 Update: A Comprehensive Review on Its ...
Its complications, while often self-limiting, can be severe, particularly in immunocompromised individuals and children. Transmission, primarily through close ...1. Introduction · 5. Treatment Of Mpox · 5.2. 1. Tecovirimat
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The Pathology of Experimental Aerosolized Monkeypox Virus ...
The principal distinguishing feature of lethal infection by aerosolized monkeypox virus in cynomolgus monkeys was severe fibrinonecrotic bronchopneumonia. A ...Article · Results · Histopathologic...<|control11|><|separator|>
[96]
Animal models of mpox virus infection and disease - ScienceDirect
The natural reservoirs of MPXV are still not completely determined, though MPXV has been isolated from Funisciurus anerythrus and Cercocebusatys, and a variety ...
[97]
with Monkeypox Virus - Ground Squirrels - CDC Stacks
A fulminant illness developed in all animals, and they died 6-9 days after infection. Virus was cultured from the blood and oropharynx several days before death ...
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Full article: Experimental inoculation of pigs with monkeypox virus ...
In conclusion, we provide the first evidence that domestic pigs are susceptible to experimental MPXV infection and can transmit the virus to contact animals.
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Monkeypox: A global threat to domestic and wild animals
In the current episode of monkeypox virus outbreak, the virus has crossed the species barrier to cause infection in dogs. In this context, the possibility of ...
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Animal models of mpox virus infection and disease - PMC
We discussed the susceptibility and pathologic features of various animals to monkeypox virus. Animal models of monkeypox virus have been used for ...
[101]
Innate Immune Response to Monkeypox Virus Infection
Aug 13, 2024 · Peer Review · Open Access · Rights ... Innate Immune Response to Monkeypox Virus Infection: Mechanisms and Immune Escape Open Access.
[102]
Evasion of the Innate Immune Type I Interferon System by ...
Monkeypox virus (MXPV) is a member of the family Poxviridae and was first reported to cause disease in humans in the Congo region of Africa in 1972 (1). MPXV is ...
[103]
Mechanisms of immune evasion of monkeypox virus - Frontiers
Jan 31, 2023 · As a member of the poxvirus family, monkeypox virus has the ability to manipulate both the innate and adaptive immune systems. It is important ...<|separator|>
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Deletion of the Monkeypox Virus Inhibitor of Complement Enzymes ...
Deletion of the Monkeypox Virus Inhibitor of Complement Enzymes Locus Impacts the Adaptive Immune Response to Monkeypox Virus in a Nonhuman Primate Model of ...
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Strong and early monkeypox virus-specific immunity associated with ...
Feb 18, 2025 · Strong and early monkeypox virus-specific immunity associated with mild disease after intradermal clade-IIb-infection in CAST/EiJ-mice.
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Review The unique immune evasion mechanisms of the mpox virus ...
In this review, we start by discussing the entry of the mpox virus and the onset of early infection, followed by an introduction to the mechanisms by which the ...
[107]
Mechanisms of immune evasion of monkeypox virus - PMC
Feb 1, 2023 · Although there is an immune evasion mechanism that strongly inhibits T-cells from recognizing monkeypox virus. The endogenous T-cell response is ...Introduction · Monkeypox Virus And... · Figure 1
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Mpox—is there a more dangerous new clade? - The Lancet
Aug 28, 2024 · This 2022 review concluded that clade I causes a significantly higher case fatality rate (CFR) than clade II (clade I: 10·6% [95% CI 8·4–13·3] ...<|separator|>
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Clade II Monkeypox Outbreaks around the World - CDC
Jul 30, 2025 · There are two types of monkeypox, clade I and clade II. The ongoing global outbreak that started in 2022 is caused by clade II.
[110]
Mpox in people with advanced HIV infection: a global case series
Feb 21, 2023 · In our series, low CD4 cell count, especially when less than 200 per mm3, was strongly associated with increasing severity of mpox disease ...<|separator|>
[111]
Mpox (monkeypox) risk and mortality associated with HIV infection
Nov 30, 2023 · The risk of dying from mpox was nearly 14-fold higher in persons living with HIV compared with non-HIV coinfected cases.
[112]
Mpox as AIDS-defining event with a severe and protracted course
Sep 28, 2023 · To our knowledge, this is the first account of a necrotising mpox in a person living with HIV, with viral shedding for more than 11 months and a ...
[113]
People with HIV are not at greater risk for severe mpox unless they ...
Aug 1, 2023 · People living with HIV are not more likely to be hospitalised with severe mpox (formerly known as monkeypox) unless they have advanced immune suppression.
[114]
Mpox: Adult and Adolescent OIs | NIH - Clinical Info .HIV.gov
Jul 14, 2025 · People with HIV who have severe mpox* or are at high risk for severe mpox** should receive directed mpox antiviral treatment (BIII). The Panel ...
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The changing epidemiology of human monkeypox—A potential ...
Over the past 5 decades, monkeypox outbreaks have been reported in 10 African countries and 4 countries outside of Africa. In addition to the re-emergence of ...
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Seasonal Patterns of Mpox Index Cases, Africa, 1970–2021 - CDC
May 5, 2024 · Across 133 confirmed mpox zoonotic index cases reported during 1970–2021 in Africa, cases occurred year-round near the equator, where climate is consistent.
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Mpox outbreak in DR Congo: What to know - Doctors Without Borders
The number of mpox cases tripled in 2023, with more than 14,000 suspected cases reported and 511 deaths. In 2024, the situation has worsened further: between ...Missing: statistics | Show results with:statistics
[118]
Time series modelling and forecasting of Monkeypox outbreak ...
This study utilizes a comprehensive dataset from the four most affected African countries, covering weekly and cumulative Mpox cases from August 6, 2023, to ...
[119]
Mpox (Monkeypox) - Africa CDC
' The first human case of monkeypox was recorded in 1970 in the Democratic Republic of the Congo (DRC), which has subsequently spread to other central and ...
[120]
Mpox worldwide overview - ECDC - European Union
On the African continent, most mpox clade I cases have been reported by the Democratic Republic of the Congo (DRC), Uganda and Burundi. Trends are decreasing in ...
[121]
Evolving Epidemiology of Mpox in Africa in 2024
Jan 29, 2025 · The case fatality rate from mpox declines with age. Historically, in endemic areas, cases were concentrated in young children, but clade IIb ...
[122]
Clade Ib Mpox in the Democratic Republic of the Congo (DRC)
Sep 5, 2024 · Since 2023, the number of mpox cases in DRC peaked above 14000 and were reported from new foci in large urban areas and transportation hubs, ...
[123]
Updating Reproduction Number Estimates for Mpox in the ...
The percentage of investigated mpox cases that were confirmed was low for the first 3 years (mean, 36%) before stabilizing for the last 7 years (mean, 76%; ...
[124]
Monkeypox emerges on a global scale: A historical review and ...
The first case of monkeypox in humans was described in the Democratic Republic of the Congo in 1970, and since then, cases have been reported primarily in ...
[125]
Multistate Outbreak of Monkeypox --- Illinois, Indiana, Kansas ... - CDC
As of July 8, 2003, a total of 71 cases of monkeypox have been reported to CDC from Wisconsin (39), Indiana (16), Illinois (12), Missouri (two), Kansas (one), ...Missing: details | Show results with:details
[126]
The Detection of Monkeypox in Humans in the Western Hemisphere
During May and June 2003, an outbreak of febrile illness with skin eruptions occurred among residents of the midwestern United States. All patients reported ...Missing: details | Show results with:details
[127]
Re-emergence of monkeypox virus outbreak in Nigeria
Nigeria recorded 262 suspected and 113 confirmed cases in 26 states and seven deaths in 16 states. Eight to 49 human monkeypox cases were recorded annually ...
[128]
Monkeypox - Nigeria Centre for Disease Control and Prevention
May 21, 2022 · The 2017 Nigerian outbreak is the largest documented outbreak of the West African clade to date. Transmission. The exact reservoir of monkeypox ...
[129]
Monkeypox in a Traveler Returning from Nigeria — Dallas, Texas ...
Apr 8, 2022 · Monkeypox is a rare, potentially serious zoonotic infection. During September 2018–June 2021, six cases among travelers from Nigeria to non-African countries ...<|separator|>
[130]
Exportation of Monkeypox Virus From the African Continent
The largest West African MPX outbreak in history began in Nigeria in September 2017 [12]. No exported cases were reported for the first 11.5 months of the ...
[131]
Monkeypox virus outbreak: a brief timeline - PMC - NIH
Recently in Pakistan, on May 29, 2022, the first suspected Monkeypox virus case was reported at the Civil hospital district Sukkur Karachi. As per the details, ...
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Monkeypox Outbreak — Nine States, May 2022 | MMWR - CDC
Jun 10, 2022 · The United Kingdom Health Security Agency (UKHSA) announced a confirmed monkeypox case on May 7, 2022, in a traveler returning from Nigeria.
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Transmission characteristics, replication patterns and clinical ...
Transmission characteristics, replication patterns and clinical manifestations of human monkeypox virus—an in-depth analysis of four cases from Germany.
[134]
Multi-country monkeypox outbreak in non-endemic countries
May 21, 2022 · Since 13 May 2022, cases of monkeypox have been reported to WHO from 12 Member States that are not endemic for monkeypox virus, across three WHO regions.
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Risk of Clade I Monkeypox Outbreaks Among U.S. MSM - Update
Jul 4, 2024 · During the ongoing clade II monkeypox outbreak that began in 2022, the main transmission route was associated with sexual activity among ...
[136]
Mpox in MSM: Tackling stigma, minimizing risk factors, exploring ...
Fever, chills, headache, and lymphadenopathy are other commonly reported symptoms among mpox patients. Unlike previous outbreaks, where these symptoms usually ...
[137]
The 2022 outbreak and the pathobiology of the monkeypox virus
Soon following this report, case numbers climbed. By June 10, 2022, more than 1,500 cases were reported in 43 countries, including Europe and North America.
[138]
Epidemiologic Features of the Monkeypox Outbreak and the Public
Nov 11, 2022 · This report describes epidemiologic features of the United States Monkeypox outbreak and CDC's emergency responses.
[139]
A timeline of the 2022 mpox outbreak - Healio
Dec 28, 2022 · An adult in Texas, at the end of August, was the first U.S. death of a person infected with mpox during the 2022 outbreak. The patient was “ ...
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Mpox outbreak - World Health Organization (WHO)
A global outbreak of mpox began in May 2022 and continues to this day. In recent months, cases have been increasing in the Democratic Republic of the Congo ...
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Recurrent Mpox: divergent virulent clades and the urgent need for ...
Apr 15, 2025 · MPXV exists as two genetically distinct clades: Clade I (formerly Congo Basin or Central African clade) and Clade II (West African clade) [39].
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Mpox Still a Continental Emergency, Africa CDC Advisory Group ...
Sep 4, 2025 · Weekly confirmed cases declined by 52 per cent between weeks 17–22 and weeks 27–32 of 2025. Yet, surges emerged in Ghana, Liberia, Kenya, Zambia ...
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Mpox Cases Rise In Ghana, Philippines And China – But Decline ...
Aug 29, 2025 · Overall, however, mpox cases are decreasing – particularly in African countries with a 28% reduction in cases between June and July, although 21 ...<|separator|>
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WHO Ends International Emergency Declaration For Mpox
Sep 5, 2025 · WHO has ended its declaration of a Public Health Emergency of International Concern (PHEIC) for Mpox, announced in August 2024, ...
[145]
Vaccine for Monkeypox Prevention in the United States - CDC
Nov 25, 2024 · ACAM2000 vaccine is approved for immunization against smallpox and could be made available for use against monkeypox under an Expanded Access ...
[146]
Monkeypox in Patient Immunized with ACAM2000 Smallpox ... - NIH
A study in 2008 reported that ACAM2000 vaccine fully protected cynomolgus monkeys after a lethal dose of monkeypox virus; 1 vaccinated animal had a minor rash ...
[147]
Comparison of the immunogenicity and protective efficacy ... - PubMed
Mar 27, 2024 · All vaccines provided robust protection against high-dose intravenous mpox virus challenge with the current outbreak strain, with ACAM2000 ...
[148]
Use of JYNNEOS (Smallpox and Mpox Vaccine, Live ... - CDC
Jun 19, 2025 · ACIP recommended the use of JYNNEOS (a live, replication-deficient vaccinia virus vaccine) for persons aged ≥18 years at risk for mpox during an mpox outbreak.
[149]
Vaccines and immunization for monkeypox: Interim guidance, 16 ...
Nov 16, 2022 · Mass vaccination is not required nor recommended for monkeypox at this time; · Primary preventive (pre-exposure) vaccination (PPV) is recommended ...
[150]
Vaccine Effectiveness of JYNNEOS against Mpox Disease in the ...
The findings suggest that JYNNEOS vaccine was effective in preventing mpox disease, and a two-dose series appeared to provide better protection.
[151]
Effectiveness of a single dose of JYNNEOS vaccine in real world
Sep 24, 2024 · Pooled prevalence of mpox infection among vaccinated individuals (breakthrough infection) in six studies was 2.19% (0.37%–5.32%). Conclusion.
[152]
Real-world effectiveness of a single dose of mpox vaccine in males
Jan 31, 2023 · Our results suggest that a single dose of subcutaneous MVA-BN in this high-risk cohort is associated with a significantly lower risk of MPXV infection.
[153]
Tecovirimat (TPOXX) for Treatment of Monkeypox - CDC
Initial analysis of data from two randomized clinical studies designed to assess the efficacy and safety of a 14-day course of tecovirimat in treating human ...
[154]
Clinical Treatment of Monkeypox - CDC
Aug 29, 2025 · Tecovirimat is an antiviral that was made available for treatment of certain patients with monkeypox under the CDC-held Expanded Access- ...
[155]
Tecovirimat for Treatment of Human Monkeypox Virus - PMC
Nov 14, 2022 · Efficacy studies have thus far been limited to animal models, with human safety trials showing no serious adverse events. Currently approved by ...
[156]
NCT05534984 | Study of Tecovirimat for Human Mpox Virus
A5418 is a randomized, placebo-controlled, double-blind study to establish the efficacy of tecovirimat for the treatment of people with laboratory-confirmed or ...Missing: therapies | Show results with:therapies
[157]
Tecovirimat for Clade I MPXV Infection in the Democratic Republic of ...
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[158]
Mpox Antiviral Drug Trial Advances as WHO Extends Global ...
Jul 17, 2025 · Currently, no FDA-approved antiviral has demonstrated human efficacy against mpox. Tecovirimat (SIGA) failed to outperform standard of care in ...Missing: therapies | Show results with:therapies
[159]
Compassionate Use of Tecovirimat for the Treatment of Monkeypox ...
Aug 22, 2022 · In this preliminary study, oral tecovirimat was well tolerated by all patients with monkeypox infection, with minimal adverse effects.<|separator|>
[160]
Treatment efficacy of cidofovir and brincidofovir against clade II ...
Sep 5, 2024 · Following intranasal infection, we show that cidofovir and brincidofovir can strongly reduce the viral replication of MPXV clade IIa and IIb ...
[161]
Antivirals With Activity Against Mpox: A Clinically Oriented Review
In this review, we explore 3 antiviral agents with activity against mpox and other orthopoxviruses: cidofovir, brincidofovir, and tecovirimat.
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Pharmacological treatment and vaccines in monkeypox virus
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[163]
Mpox: disease manifestations and therapeutic development
Aug 11, 2025 · Current antiviral agents, including tecovirimat and brincidofovir, have demonstrated uncertain or disappointing efficacy in preclinical and ...
[164]
Determining Effective Therapy for Mpox
Apr 16, 2025 · Tecovirimat could not be approved for the treatment of mpox under the Animal Rule because human efficacy studies are feasible and ethical.
[165]
Small molecule direct-acting antivirals for treatment of mpox
Sep 30, 2025 · Effective antivirals against ORPVs are needed for the current outbreak of mpox and potential future ORPV outbreaks. •. Monkeypox virus outbreaks ...
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Isolation and Infection Control At Home | Monkeypox - CDC
Sep 13, 2024 · CDC recommends that people with monkeypox remain isolated at home or at another location for the duration of illness, but that might not be ...
[167]
Modelling the effectiveness of an isolation strategy for managing ...
Aug 26, 2024 · These findings warrant caution against a resurgence of mpox and highlight the importance of maintaining nonpharmaceutical interventions (NPIs).
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Public Health Strategies for Monkeypox - CDC
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Surveillance, case investigation and contact tracing for Monkeypox
Mar 20, 2024 · The overall goal of surveillance, case investigation and contact tracing for mpox is to detect new outbreaks and stop transmission, protect people at risk.Missing: pharmaceutical interventions isolation
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Monkeypox (Mpox) requires continued surveillance, vaccines ...
May 11, 2023 · Fortunately, classical public health measures (e.g., isolation, contact tracing and quarantine) and vaccination have blunted the spread of ...<|separator|>
[171]
Effectiveness of Contact Tracing for Viral Disease Mitigation ... - NIH
Contact tracing in association with quarantine and isolation is an important public health tool to control outbreaks of infectious diseases.
[172]
Interim guidance on infection prevention and control for patients with ...
Nov 13, 2024 · Healthcare settings should implement droplet and contact precautions, with appropriate PPE for all suspected, probable and confirmed mpox.
[173]
Clinical management and infection prevention and control for ...
Jun 10, 2022 · WHO has developed interim rapid response guidance for the clinical management and infection prevention and control of monkeypox for health care and community ...
[174]
Monkeypox Virus Outbreak 2022: Key Epidemiologic, Clinical ...
Monkeypox is a zoonotic infection which manifests as dermatologic lesions that may be painful or pruritic and can appear on the face, trunk, extremities, ...
[175]
Assessing the impact of non-pharmaceutical interventions against ...
In Australia, NPIs led to a 38% overall reduction in disease incidence, demonstrating their broad effectiveness in curbing infectious disease transmission.
[176]
Modelling the effectiveness of an isolation strategy for managing ...
Aug 26, 2024 · Ensuring sustainable implementation of NPIs remains key to responding effectively to future outbreaks of mpox and other diseases.
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Modelling the potential spread of Clade Ib MPXV in Asian cities
May 12, 2025 · Various NPIs, particularly isolating infected cases, are recommended for curbing the disease outbreak due to their feasibility and effectiveness ...
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Dutch study finds no evidence of monkeypox transmission before ...
Nov 22, 2022 · "These findings suggest that the introduction of MPXV in Dutch sexual networks of MSM started somewhere at the end of April 2022. This coincides ...
[179]
Why the monkeypox outbreak is mostly affecting men who have sex ...
Jun 20, 2022 · The virus may have made its way into highly interconnected sexual networks within the MSM community, where it can spread in ways that it cannot in the general ...
[180]
https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2023.28.17.2200869
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Monkeypox: Early estimation of basic reproduction number R0 in ...
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Estimation of local transmissibility in the early phase of monkeypox ...
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Decoding mpox: a systematic review and meta-analysis of the ...
Jan 31, 2025 · The epidemic peaked between August and September 2022 in Europe and the Americas whereas transmission has continued in African countries. For ...
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Prevention of sexual transmission of mpox: a systematic review and ...
Jul 3, 2024 · They found a significant reduction in proportion of MSM with mpox who provided location details for their sexual contacts after the vaccination ...
[185]
Expert: Here's What to Know About the MPox Outbreak Emergency
Aug 21, 2024 · Clade 2, with less severe illness and less than 0.2% fatality rate, was the strain responsible for the 2022 outbreak originating in West Africa.
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The clinical manifestations and severity of the 2022 monkeypox ...
[5] estimated a case fatality rate of 0.01% in non-endemic areas, compared to 1.81% in endemic regions in 2022. These rates are remarkably lower than the ...
[187]
The CDC Domestic Mpox Response — United States, 2022–2023
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[188]
Monkeypox isn't much of a threat to the public, a White House official ...
May 23, 2022 · So far in the U.S., one case of monkeypox has been confirmed in Massachusetts. A few more are suspected in New York, Florida and Utah, according ...
[189]
Monkeypox isn't the disease we should be worried about | John Vidal
May 25, 2022 · Most worrying for humans is not monkeypox, plague or even Ebola, which sound dangerous and exotic but are actually more or less controllable now with vaccines.
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Public Perceptions About Monkeypox on Twitter: Thematic Analysis
Nov 3, 2023 · The most common themes from our study were monkeypox doubts and media, each accounting for 22% (44/200) of the posts.
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Monkeypox : symptoms, treatment, prevention - Institut Pasteur
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Misinformation and Public Health Messaging in the Early Stages of ...
Jun 6, 2023 · This study aims to observe topical themes occurring in a large-scale collection of tweets about mpox using deep learning.
[193]
The WHO Declaration of Monkeypox as a Global Public Health ...
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[194]
Inequity in the global distribution of monkeypox vaccines - PMC
In this article, we briefly discussed general aspects of the disease, including its surveillance, the current global context of challenges for mpox vaccination, ...Missing: biases | Show results with:biases
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Monkeypox: wealthy countries must avoid their COVID-19 mistakes
Jul 26, 2022 · Having ignored the disease for decades, high-income countries must share vaccines and treatments quickly with other nations.Missing: failures | Show results with:failures
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Africans see inequity in monkeypox response elsewhere | AP News
Jun 1, 2022 · Limited vaccine supply and competing health priorities have meant that immunization against monkeypox hasn't been widely pursued in Africa, said ...
[197]
U.S. Domestic Response to the 2022 Monkeypox Outbreak
Aug 5, 2022 · On August 4, 2022, the Department of Health and Human Services (HHS) Secretary declared a Public Health Emergency for the monkeypox outbreak.
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Reversing Inequity in Mpox Vaccine Distribution, Fulton County ...
Nov 8, 2023 · Initial events showed large racial/ethnic disparities in vaccine administration favoring White participants, despite the fact that the majority ...
[199]
Demographic Disparities in Mpox Vaccination Series Completion, by ...
Jul 28, 2023 · This report describes demographic disparities among people who completed the 2-dose mpox vaccination series by intradermal or subcutaneous ...Missing: resource allocation
[200]
Key Questions About the Current U.S. Monkeypox Outbreak - KFF
Jul 27, 2022 · While the U.S. response to monkeypox has ramped up over time, after early criticism, the outbreak is expanding significantly, and challenges ...
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https://www.nature.com/articles/s41390-025-04461-8
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Mpox virus and the perils of neglect in Africa | BMJ Global Health
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Africa CDC Declares Mpox Emergency, Moving to Lead Response
Aug 13, 2024 · The Africa Centers for Disease Control and Prevention (CDC) has declared a public health emergency of continental security over mpox.
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The 2024 Public Health Emergency of International Concern
On August 14, 2024, the World Health Organization (WHO) declared the current mpox outbreak a global Public Health Emergency of International Concern (PHEIC).
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Temporary recommendations - World Health Organization (WHO)
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[206]
Challenges in Global Distribution and Equitable Access to ...
A significant contributor to vaccine access inequities, especially in low- and middle-income countries, is the underreporting of Mpox cases, especially in the ...Missing: biases | Show results with:biases
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Mpox virus and the perils of neglect in Africa - PMC - PubMed Central
Nov 18, 2024 · This commentary underlines the perils of neglecting Mpox, exploring three key factors that have contributed to its re-emergence and spread.