Monkeypox, also known as simian orthopox, is an infectious disease caused by the monkeypox virus, a virus closely related to that of smallpox. This disease is a zoonosis, meaning that the virus circulates in an animal reservoir (rodents), and is sometimes transmitted to humans, who are an accidental host. In some cases, the disease can be transmitted between humans. It is endemic in West and Central Africa, where cases, and sometimes epidemics, are regularly reported. In the last five years, people who have travelled have been diagnosed with the disease on their return from Africa, but this has remained rare.
Since the beginning of May 2022, in a highly unusual development, a greater number of cases have been reported for the first time in several European countries, North and South America and Australia - with a first case in Switzerland on 21 May, followed by a second in Geneva on 24 May... To date, the vast majority of these recently reported cases have had a favourable outcome, with remission of symptoms. Nonetheless, around 10% of those diagnosed require hospitalisation.