Mpox.

Human mpox (formerly known as monkeypox) is a zoonotic disease that causes a smallpox-like infection in humans. The mpox virus, the causative agent of mpox, was first reported to cause human disease in a 9-month-old infant in the Democratic Republic of the Congo in 1970. Since that time, periodic outbreaks in primarily endemic regions have occurred, typically secondary to transmission from wildlife reservoirs. However, in May 2022, after a rapid rise in worldwide cases in largely nonendemic countries, the World Health Organization declared mpox a Public Health Emergency of International Concern. As of January 2022, more than 80,000 cases of mpox in nonendemic countries have occurred, and more than 25,000 cases in the United States alone. Most of these cases occurred in adults, with the highest frequency among men who had sex with men. Children and adolescents represented only 0.3% of US cases as of September 2022, with most infections in young children the result of direct contact with an infected household member. Although infection remains uncommon in US children and teens, pediatric emergency and urgent care providers should be aware of the clinical features, treatment, and prophylaxis of this important emerging infectious disease.