2022–2023 mpox outbreak in Brazil

Mpox (formerly known as monkeypox)[2] is an infectious viral disease that can occur in humans and some other animals.[3] Symptoms include a rash that forms blisters and then crusts over, fever, and swollen lymph nodes.[3] The time from exposure to onset of symptoms ranges from five to twenty-one days and symptoms typically last from two to four weeks.[4][5] There may be mild symptoms, and it may occur without any symptoms being apparent.[4][6] Cases may be severe, especially in children, pregnant women or people with suppressed immune systems.[7]

The disease is caused by the monkeypox virus,[lower-alpha 1] a zoonotic virus in the genus Orthopoxvirus.[8] The variola virus, the causative agent of smallpox, is also in this genus.[9] It may spread from infected animals by handling infected meat or via bites or scratches.[10] Human-to-human transmission can occur through exposure to infected body fluids or contaminated objects, by small droplets, and possibly through the airborne route.[3][10] 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.[11] Diagnosis can be confirmed by testing a lesion for the virus's DNA.[12]

There is no known cure.[13] 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.[14] A newer smallpox and mpox vaccine based on modified vaccinia Ankara has been approved, but with limited availability.[4] Other measures include regular hand washing and avoiding sick people and animals.[15] Antiviral drugs, cidofovir and tecovirimat, vaccinia immune globulin and the smallpox vaccine may be used during outbreaks.[16][17] The illness is usually mild and most of those infected will recover within a few weeks without treatment.[17] Estimates of the risk of death vary from 1% to 10%, although few deaths as a consequence of mpox have been recorded since 2017.[18]

An outbreak of mpox, a viral disease then commonly known as "monkeypox", was confirmed in May 2022.[19] The initial cluster of cases was found in the United Kingdom,[20] where the first case was detected in London on 6 May 2022[21] in a patient with a recent travel history from Nigeria (where the disease is endemic).[22] On 16 May, the UK Health Security Agency (UKHSA) confirmed four new cases with no link to travel to a country where mpox is endemic. All four cases appeared to have been infected in London.[23] From 18 May 2022 until May 2023, cases were reported from several countries and regions, predominantly in Europe and in the Americas but also in Asia, in Africa, and in Oceania.[30] The outbreak marked the first time mpox had spread widely outside Central and West Africa.

On 23 July, the Director-General of the World Health Organization (WHO), Tedros Adhanom Ghebreyesus, declared the outbreak a public health emergency of international concern (PHEIC).[31] As of 18 March 2023, there had been a total of 86,516 confirmed cases in over 113 countries.[32][33]In May 2023, the World Health Organization declared an end to the global health emergency declared in response to the worldwide outbreak of mpox virus.[34]