Incubation Period and Serial Interval of Mpox in 2022 Global Outbreak Compared with Historical Estimates.

Understanding changes in the transmission dynamics of mpox requires comparing recent estimates of key epidemiologic parameters with historical data. We derived historical estimates for the incubation period and serial interval for mpox and contrasted them with pooled estimates from the 2022 outbreak. Our findings show the pooled mean infection-to-onset incubation period was 8.1 days for the 2022 outbreak and 8.2 days historically, indicating the incubation periods remained relatively consistent over time, despite a shift in the major mode of transmission. However, we estimated the onset-to-onset serial interval at 8.7 days using 2022 data, compared with 14.2 days using historical data. Although the reason for this shortening of the serial interval is unclear, it may be because of increased public health interventions or a shift in the mode of transmission. Recognizing such temporal shifts is essential for informed response strategies, and public health measures remain crucial for controlling mpox and similar future outbreaks.

Effectiveness of historical smallpox vaccination against mpox clade II in men in Denmark, France, the Netherlands and Spain, 2022.

BackgroundIn 2022, a global monkeypox virus (MPXV) clade II epidemic occurred mainly among men who have sex with men. Until early 1980s, European smallpox vaccination programmes were part of worldwide smallpox eradication efforts. Having received smallpox vaccine > 20 years ago may provide some cross-protection against MPXV.AimTo assess the effectiveness of historical smallpox vaccination against laboratory-confirmed mpox in 2022 in Europe.MethodsEuropean countries with sufficient data on case vaccination status and historical smallpox vaccination coverage were included. We selected mpox cases born in these countries during the height of the national smallpox vaccination campaigns (latest 1971), male, with date of onset before 1 August 2022. We estimated vaccine effectiveness (VE) and corresponding 95% CI for each country using logistic regression as per the Farrington screening method. We calculated a pooled estimate using a random effects model.ResultsIn Denmark, France, the Netherlands and Spain, historical smallpox vaccination coverage was high (80-90%) until the end of the 1960s. VE estimates varied widely (40-80%, I2 = 82%), possibly reflecting different booster strategies. The pooled VE estimate was 70% (95% CI: 23-89%).ConclusionOur findings suggest residual cross-protection by historical smallpox vaccination against mpox caused by MPXV clade II in men with high uncertainty and heterogeneity. Individuals at high-risk of exposure should be offered mpox vaccination, following national recommendations, regardless of prior smallpox vaccine history, until further evidence becomes available. There is an urgent need to conduct similar studies in sub-Saharan countries currently affected by the MPXV clade I outbreak.

Intrafamily Transmission of Monkeypox Virus, Central African Republic, 2018.

Monkeypox is a rare viral zoonotic disease; primary infections are reported from remote forest areas of Central and West Africa. We report an investigation of a monkeypox outbreak in Lobaye, southwest Central African Republic, in October 2018.

Diagnosis of Imported Monkeypox, Israel, 2018.

We report a case of monkeypox in a man who returned from Nigeria to Israel in 2018. Virus was detected in pustule swabs by transmission electron microscopy and PCR and confirmed by immunofluorescence assay, tissue culture, and ELISA. The West Africa monkeypox outbreak calls for increased awareness by public health authorities worldwide.

Levels of antibodies against the monkeypox virus compared by HIV status and historical smallpox vaccinations: a serological study.

Men who have sex with men and people living with HIV are disproportionately affected in the 2022 multi-country monkeypox epidemic. The smallpox vaccine can induce cross-reactive antibodies against the monkeypox virus (MPXV) and reduce the risk of infection. Data on antibodies against MPXV induced by historic smallpox vaccination in people with HIV are scarce. In this observational study, plasma samples were collected from people living with and without HIV in Shenzhen, China. We measured antibodies binding to two representative proteins of vaccinia virus (VACV; A27L and A33R) and homologous proteins of MPXV (A29L and A35R) using an enzyme-linked immunosorbent assay. We compared the levels of these antibodies between people living with and without HIV. Stratified analyses were performed based on the year of birth of 1981 when the smallpox vaccination was stopped in China. Plasma samples from 677 people living with HIV and 746 people without HIV were tested. A consistent pattern was identified among the four antibodies, regardless of HIV status. VACV antigen-reactive and MPXV antigen-reactive antibodies induced by historic smallpox vaccination were detectable in the people born before 1981, and antibody levels reached a nadir during or after 1981. The levels of smallpox vaccine-induced antibodies were comparable between people living with HIV and those without HIV. Our findings suggest that the antibody levels against MPXV decreased in both people living with and without HIV due to the cessation of smallpox vaccination.

The changing epidemiology of human monkeypox-A potential threat? A systematic review.

Monkeypox, a zoonotic disease caused by an orthopoxvirus, results in a smallpox-like disease in humans. Since monkeypox in humans was initially diagnosed in 1970 in the Democratic Republic of the Congo (DRC), it has spread to other regions of Africa (primarily West and Central), and cases outside Africa have emerged in recent years. We conducted a systematic review of peer-reviewed and grey literature on how monkeypox epidemiology has evolved, with particular emphasis on the number of confirmed, probable, and/or possible cases, age at presentation, mortality, and geographical spread. The review is registered with PROSPERO (CRD42020208269). We identified 48 peer-reviewed articles and 18 grey literature sources for data extraction. The number of human monkeypox cases has been on the rise since the 1970s, with the most dramatic increases occurring in the DRC. The median age at presentation has increased from 4 (1970s) to 21 years (2010-2019). There was an overall case fatality rate of 8.7%, with a significant difference between clades-Central African 10.6% (95% CI: 8.4%- 13.3%) vs. West African 3.6% (95% CI: 1.7%- 6.8%). Since 2003, import- and travel-related spread outside of Africa has occasionally resulted in outbreaks. Interactions/activities with infected animals or individuals are risk behaviors associated with acquiring monkeypox. Our review shows an escalation of monkeypox cases, especially in the highly endemic DRC, a spread to other countries, and a growing median age from young children to young adults. These findings may be related to the cessation of smallpox vaccination, which provided some cross-protection against monkeypox, leading to increased human-to-human transmission. The appearance of outbreaks beyond Africa highlights the global relevance of the disease. Increased surveillance and detection of monkeypox cases are essential tools for understanding the continuously changing epidemiology of this resurging disease.

La viruela símica como enfermedad zoonótica viral y reemergente en el actual contexto sanitario mundial / Mpox as a Viral Zoonotic Disease Reemerging in the Current Global Health Context

Introducción: La viruela símica es una enfermedad zoonótica que también se trasmite de persona a persona por contacto estrecho. En el brote actual hasta el 31 de agosto de 2022 se reportaban 50 496 casos diagnosticados en 101 países, por lo que se consideró una situación preocupante por la Organización Mundial de la Salud. Objetivo: Exponer información actualizada sobre la viruela símica en el contexto sanitario actual. Métodos: Se realizó una búsqueda de literatura científica en las bases de datos ScienceDirect, PubMed/Medline, SciELO y Google Académico, mediante los descriptores o palabras relacionadas con la enfermedad, para encontrar revisiones, comunicados, informes, distintos artículos de revistas, entre otros documentos especializados de producción científica. Se seleccionó un total de 30 citas, actualizadas en su totalidad. Desarrollo: Desde su identificación en humanos se han reportado brotes de viruela símica en varios países; el más preocupante, ha sido el de reciente declaración en 2022, debido a la presencia de casos en países no endémicos, con un alcance geográfico extenso. Las manifestaciones clínicas pueden cursar con síntomas leves, como erupciones en la cara y el resto del cuerpo, fiebre, cefalea, mialgias y fatiga, por lo que no constituye una enfermedad potencialmente mortal; sin embargo, de presentarse comorbilidades la evolución podría ser tórpida. Conclusiones: La presencia de casos de viruela símica en humanos se ha mantenido desde su aparición, sin encontrar un tratamiento específico y vacunas autorizadas para su administración, lo que podría generar un aumento de contagios y fallecidos(AU)

Introduction: Mpox is a zoonotic disease also transmitted from person to person by close contact. The current outbreak, up to August 31, 2022, reported 50 496 diagnosed cases from 101 countries; therefore; it was considered a situation of concern by the World Health Organization. Objective: To present updated information on Mpox in the current health context. Methods: A scientific literature search was carried out in the databases ScienceDirect, PubMed/Medline, SciELO and Google Scholar, using descriptors or words related to the disease, in order to find reviews, communications, reports, different journal articles, among other specialized documents of scientific production. A total of 30 entirely updated citations were selected. Development: Since Mpox was identified in humans, outbreaks of the disease have been reported in several countries; the most worrisome has been reported recently in 2022, due to the presence of cases in nonendemic countries, with an extensive geographical scope. The clinical manifestations may occur with mild symptoms, such as rash on the face or the rest of the body, fever, headache, myalgia and fatigue; therefore, it is not a potentially mortal disease. However, in case of comorbidity, the evolution could be torpid. Conclusions: Mpox cases in humans has been present since its appearance, without any specific treatment or vaccines authorized to be administered, which could generate an increase in contagions and deaths(AU)

Emerging infectious diseases at the beginning of the 21st century.

The emergence and re-emergence of infectious diseases involves many interrelated factors. Global interconnectedness continues to increase with international travel and trade; economic, political, and cultural interactions; and human-to-human and animal-to-human interactions. These interactions include the accidental and deliberate sharing of microbial agents and antimicrobial resistance and allow the emergence of new and unrecognized microbial disease agents. As the 21st century begins, already new agents have been identified, and new outbreaks have occurred. Solutions to limiting the spread of emerging infectious diseases will require cooperative efforts among many disciplines and entities worldwide. This article defines emerging infectious diseases, summarizes historical background, and discusses factors that contribute to emergence. Seven agents that have made a significant appearance, particularly in the 21st century, are reviewed, including: Ebola and Marburg hemorrhagic fevers, human monkeypox, bovine spongiform encephalopathy, severe acute respiratory syndrome (SARS), West Nile virus, and avian influenza. The article provides for each agent a brief historical background, case descriptions, and health care implications.

Status of human monkeypox: clinical disease, epidemiology and research.

Monkeypox, a vesiculo-pustular rash illness, was initially discovered to cause human infection in 1970 through the World Health Organization (WHO)-sponsored efforts of the Commission to Certify Smallpox Eradication in Western Africa and the Congo Basin. The virus had been discovered to cause a nonhuman primate rash illness in 1958, and was thus named monkeypox. The causative agents of monkeypox and smallpox diseases both are species of Orthopoxvirus. Orthopoxvirus monkeypox, when it infects humans as an epizootic, produces a similar clinical picture to that of ordinary human smallpox. Since 1970, extensive epidemiology, virology, ecology and public health research has enabled better characterization of monkeypox virus and the associated human disease. This work reviews the progress in this body of research, and reviews studies of this "newly" emerging zoonotic disease.