Monkeypox is an infectious disease caused by the monkeypox virus that can occur in certain animals, including humans. Symptoms begin with fever, headache, muscle pains, swollen lymph nodes, and feeling tired. This is followed by a rash that forms blisters and crusts over. The time from exposure to onset of symptoms is usually 7 to 14 days. The duration of symptoms is typically two to four weeks.Monkeypox may be spread from handling bushmeat, an animal bite or scratch, body fluids, contaminated objects, or close contact with an infected person. The virus normally circulates among certain rodents. Diagnosis can be confirmed by testing a lesion for the virus's DNA. The disease can appear similar to chickenpox.The smallpox vaccine can prevent infection with 85% effectiveness. In 2019, a monkeypox vaccine, Jynneos, was approved for adults in the United States. The current standard for treatment is tecovirimat, an antiviral that is specifically intended to treat infections with orthopoxviruses such as smallpox and monkeypox. It is approved for the treatment of monkeypox in the European Union and the United States. Cidofovir or brincidofovir may also be useful. Reports of the risk of death, if untreated, are as high as 10% to 11% in the Congo Basin (Central African) clade of monkeypox.Monkeypox was first identified in 1958 among laboratory monkeys in Copenhagen, Denmark. Monkeys are not a natural reservoir of the virus. The first cases in humans were found in 1970 in the Democratic Republic of the Congo. An outbreak that occurred in the United States in 2003 was traced to a pet store where rodents imported from Ghana were sold. The 2022 monkeypox outbreak represents the first incidence of widespread community transmission outside of Africa, which began in the United Kingdom in May 2022, with subsequent cases confirmed in at least 12 countries, including several in Europe, North America, as well as Australia and Israel.