Monkeypox Virus: What Every Biologist Needs to Know

Monkeypox (MPX) is a rare zoonotic viral disease endemic in Central and West Africa caused by Monkeypox virus (MPXV), an orthopoxvirus belonging to the same family as human smallpox. Until recently, cases reported outside Africa were sporadic and generally associated with travel. However, in May 2022, an unusual global spread of MPOX was observed, with cases reported in several non-endemic countries across various continents. In 2024, a significant increase in the number of confirmed cases of Mpox and associated deaths was observed worldwide, justifying its classification as a Public Health Emergency of International Concern. The causes of this unusual spread are still under investigation, but may be related to increased international travel and a decrease in herd immunity to orthopoxviruses. Transmission of the virus currently appears to occur primarily through close, intimate contact, particularly among men who have sex with men. MPOX is generally a self-limited disease, with an incubation period ranging from 7 to 14 days, and sometimes up to 21 days. In 2022, the following countries recorded the following confirmed cases: United Kingdom: 575 cases; Spain: 497 cases; Germany: 338 cases; Portugal: 276 cases; France: 183 cases; Canada: 167 cases; United States of America: 113 cases; Netherlands: 95 cases; Italy: 71 cases; Israel: 5 cases; and Morocco: 3 cases. As of 14 December 2023, a total of 91,778 laboratory-confirmed cases of MPXV infection, including 167 deaths, have been reported from 116 countries/territories/areas across the six World Health Organization (WHO) regions. Faced with a high epidemic risk in Morocco, the Ministry of Health and Social Protection has implemented a national plan for surveillance and response to Mpox. The implementation of reliable and rapid laboratory tests is crucial for effective disease identification and control. To this end, WHO has issued guidelines for clinical laboratories, including: recommended test types, sample selection and collection criteria, appropriate diagnostic methods, interpretation of results, biosafety requirements, and recommendations for therapeutic management and vaccination. Molecular tests, particularly PCR-based techniques, are recommended as confirmatory methods. For symptomatic patients, skin lesion samples are most appropriate. In the prodromal or presymptomatic phase, the collection of blood, oropharyngeal swabs, and skin lesion samples is recommended.