Monkeypox is an infectious viral disease that can occur in humans and some other animals. Symptoms include fever, swollen lymph nodes, and a rash that forms blisters and then crusts over. The time from exposure to onset of symptoms ranges from five to twenty-one days. The duration of symptoms is typically two to four weeks. There may be mild symptoms, and it may occur without any symptoms being known. The classic presentation of fever and muscle pains, followed by  swollen glands, with lesions all at the same stage, has not been found to be common to all outbreaks. Cases may be severe, especially in children, pregnant women or people with suppressed immune systems.The disease is caused by the monkeypox virus, a zoonotic virus in the genus Orthopoxvirus. The variola virus, the causative agent of smallpox, is also in this genus. Of the two types in humans, clade II (formerly West African clade) causes a less severe disease than the Central African (Congo basin) type. It may spread from infected animals by handling infected meat or via bites or scratches. Human-to-human transmission can occur through exposure to infected body fluids or contaminated objects, by small droplets, and possibly through the airborne route. People can spread the virus from the onset of symptoms until all the lesions have scabbed and fallen off; with some evidence of spread for more than a week after lesions have crusted. Diagnosis can be confirmed by testing a lesion for the viruss DNA.There is no known cure.
A study in 1988 found that the smallpox vaccine was around 85% protective in preventing infection in close contacts and in lessening the severity of the disease. A newer smallpox and monkeypox vaccine based on modified vaccinia Ankara has been approved, but with limited availability. Other measures include regular hand washing and avoiding sick people and animals. Antiviral drugs, cidofovir and tecovirimat, vaccinia immune globulin and the smallpox vaccine may be used during outbreaks. The illness is usually mild and most of those infected will recover within a few weeks without treatment. Estimates of the risk of death vary from 1% to 10%, although few deaths as a consequence of monkeypox have been recorded since 2017.Several species of mammals are suspected to act as a natural reservoir of the virus. Although it was once thought to be uncommon in humans, the quantity and severity of outbreaks has significantly increased since the 1980s, possibly as a result of waning immunity since the stopping of routine smallpox vaccination. The first cases in humans were found in 1970 in the Democratic Republic of the Congo (DRC). There have been sporadic cases  in Central and West Africa, and it is endemic in the DRC. The 2022 monkeypox outbreak represents the first incidence of widespread community transmission outside of Africa, which was initially identified in the United Kingdom in May 2022, with subsequent cases confirmed in at least 74 countries in all continents except Antarctica.