In May 2022, the Centers for Disease Control and Prevention (CDC) began tracking cases of mpox (formerly named monkeypox) in the United States, a disease caused by infection with the monkeypox virus. Already in 2024, more than 1,900 U.S. cases have been reported to the CDC. The World Health Organization declared it a global outbreak in 2022 and again in August 2024 after the clade II strain emerged.