Coloured transmission electron micrograph (TEM) of mpox (previously monkeypox) virus particles (red) within an infected cell (blue). In humans mpox infection causes fever, fatigue, body aches, swollen glands and a rash of fluid-filled blisters. Transmission can occur through direct contact with infectious skin or other lesions, bites or scratches from infected animals, or indirectly through contact with contaminated objects. The mpox virus was first discovered in 1958 in two outbreaks of a pox-like disease among colonies of research monkeys, though small mammals such as rodents are believed to be the natural hosts. The first human case was recorded in 1970 in the Democratic Republic of the Congo, and it is endemic in central and western Africa. Most people recover from mpox infection within 2-4 weeks, and a vaccine is available.