Monkeypox virus is an orthopoxvirus which was isolated for the first time in the 1950s from a group of unwell monkeys. It is in the same genus as variola that causes smallpox and vaccinia viruses. Although they are famously suspicious, there’s no clear evidence that monkeys are the primary natural reservoir of the Monkeypox virus. However, humans and monkeys are considered to be incidental hosts. Monkeypox is usually acquired by humans through contact with animal fluid or bites, nevertheless, the human-to-human infection may occur through contact with infectious skin, exposure to large respiratory droplets and/or prolonged face-to-face contact within 6 feet for more than 3 hours without appropriate protections. Interestingly, the most recent outbreak that took place in May 2022 in non-endemic places has been linked to some sexual activities through an unknown mechanism. After the discontinuation of smallpox vaccination in 1979, monkeypox was endemic in Central and West Africa with sporadic cases reported in other non-endemic countries, mostly in returning travellers from endemic areas. In 2003, the United States of America reported an outbreak of monkeypox virus from infected prairie dogs who were in contact with imported animals from Africa. The incubation period of the monkeypox virus is 6 to 13 days with a range of 5 to 21 days. The most common presenting features of monkeypox are rash, fever, lymphadenopathy, chills, and myalgias. It is usually a mild disease that might be associated with nausea and vomiting, and Most of the infected persons recover without intervention. However, more serious cases might require hospitalization and supportive care. Laboratory confirmatory tests are essential to differentiate monkeypox from fever and rash diseases. These include (i) virus isolation in mammalian cell cultures, (ii) direct electron microscopy, (iii) real-time polymerase chain reaction (PCR), and (iv) enzyme-linked immunosorbent assay (ELISA), and (v) immunofluorescent antibody assay. The public health authorities should be notified according to most states’ health regulations. Varicella, smallpox, herpes simplex infection, and other orthopoxvirus infections are the differential diagnosis for Monkeypox. Tecovirimat and brincidofovir are the approved antiviral treatment for smallpox in the United States as their activity against monkeypox are approved in animals and are expected to be effective in human infection. Cidofovir has in vitro effect against monkeypox with a particular effect against lethal monkeypox in animal models. Contact, droplet, and airborne standard precaution measures are essential for any hospitalized patient with a generalized unknown vesicular rash as monkeypox and smallpox are part of the differential diagnosis. Pre- and post-exposure smallpox vaccination prophylaxis are reasonable options for select circumstances with appropriate notifications of public health authorities. In this review, we will discuss briefly the virology, geographic distribution, diagnosis and management of monkeypox infection.
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