Mpox is caused by the monkeypox virus, MPXV, of the genus Orthopoxvirus. The virus is related to the classical human smallpox viruses (variola, smallpox) and cowpox viruses, also known as zoonoses.
Mpox occurs naturally in West and Central Africa and has been detected in several rodent species (squirrels, rats, dormice) and shrews. These rodents are therefore thought to be the natural reservoir for MPXV.
In addition to a number of animal species such as prairie dogs and primates, humans are also susceptible to infection, making Mpox a zoonotic disease.
Until May 2022, human infections occurred mainly as traveller's disease in people who had been to African countries where the virus is naturally present. Cases occurring in different countries from May 2022 onwards represent the first widespread human-to-human transmission outside Africa.
Since mid-2024, human cases have increased in several countries in central Africa. Because of this increase, WHO has declared Mpox a public health emergency of international concern (PHEIC). This event also essentially involves chains of infection from person to person.
Links
World Organisation for Animal Health (WOAH; founded as Office International des Épizooties (WOAH))
Human infections:
Robert Koch-Institut (RKI; in German language only)
World Health Organization (WHO)
European Centre for Disease Prevention and Control (ECDC)