The Disease Ecology, Epidemiology, Clinical Manifestations, Management, Prevention, and Control of Increasing Human Infections with Animal Orthopoxviruses

Wilderness Environ Med. 2021 Dec;32(4):528-536. doi: 10.1016/j.wem.2021.08.003. Epub 2021 Sep 22.


Zoonotic orthopoxvirus outbreaks have occurred repeatedly worldwide, including monkeypox in Africa and the United States, cowpox in Europe, camelpox in the Middle East and India, buffalopox in India, vaccinia in South America, and novel emerging orthopoxvirus infections in the United States, Europe, Asia, and South America. Waning smallpox immunity may increase the potential for animal-to-human transmission followed by further community transmission person-to-person (as demonstrated by monkeypox and buffalopox outbreaks) and by contact with fomites (as demonstrated by camelpox, cowpox, and, possibly, Alaskapox). The objectives of this review are to describe the disease ecology, epidemiology, clinical manifestations, prevention, and control of human infections with animal orthopoxviruses and to discuss the association with diminished population herd immunity formerly induced by vaccinia vaccination against smallpox. Internet search engines were queried with key words, and case reports, case series, seroprevalence studies, and epidemiologic investigations were found for review.

Keywords: buffalopox; camelpox; cowpox; monkeypox; smallpox; vaccinia; variola; zoonoses.

Publication types

  • Review

MeSH terms

  • Animals
  • Humans
  • Orthopoxvirus*
  • Poxviridae Infections* / epidemiology
  • Poxviridae Infections* / prevention & control
  • Seroepidemiologic Studies
  • United States
  • Vaccinia virus
  • Variola virus*