Monkeypox (mpox) is a viral infection of zoonotic origin caused by the mpox virus (MPXV), which is an Orthopoxvirus. Until 2021, mpox cases were mostly confined to endemic regions of Central Africa and West Africa, with sporadic cases in nonendemic areas linked to travel to endemic regions or following animal exposure. The global 2022 outbreak (caused by a new lineage B.1, clade 2b virus) was identified in May 2022 across many countries worldwide, with the first mpox case reported from Europe. As of 31 October 2024, over 126 countries reported more than 1,15,000 laboratory-confirmed cases of mpox, including 255 deaths. While previous outbreaks showed limited interhuman transmission and could be controlled, the 2022 outbreak showed rapid person-to-person transmission, mainly affecting bisexual men and male homosexuals. During this outbreak, the virus probably spread through close contact and sexual contact, with most patients having no prior animal exposure or travel to endemic regions. The clinical presentation of mpox cases during the 2022 outbreak was atypical, with lesions seen predominantly in the anogenital regions as opposed to the typical mpox rash. The preferred test to confirm mpox diagnosis is by detection of viral DNA by real-time or conventional polymerase chain reaction (PCR) test from cutaneous lesion samples. There is no specific approved treatment for mpox. Management of mild infections mainly involves supportive care. Patients with severe infections or complications should be hospitalized for management, and antiviral agents such as tecovirimat, cidofovir, or brincidofovir can be administered. Smallpox vaccines (JYNNEOS or ACAM2000) provide cross-protection against mpox and should be considered for prophylaxis, especially in healthcare workers and for other contacts of mpox cases. In this review, we discuss the virology, epidemiology, pathogenesis, clinical manifestations, treatment, and vaccination of mpox due to growing concern of the MPXV.
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