2022–2023 mpox outbreak in the United States

2022–2024 mpox outbreak in the United States
Spread of mpox by US state as of September 24, 2022
DiseaseMpox
Virus strainMonkeypox virus (West African clade)
LocationUnited States
Index caseBoston, Massachusetts
Arrival dateMay 17, 2022 (3 years, 1 month and 1 day ago)
Dateas of May 13, 2025
Confirmed cases34,730
Deaths
63
Government website
www.cdc.gov/poxvirus/mpox/response/2022/

The 2022–2023 mpox outbreak in the United States was part of the larger outbreak of human mpox caused by the West African clade of the monkeypox virus. The United States was the fourth country outside of the African countries with endemic mpox to experience an outbreak in 2022. The first case was documented in Boston, Massachusetts, on May 17, 2022. As of August 2022, mpox had spread to all 50 states in the United States, as well as Washington, D.C., and Puerto Rico. The United States had the highest number of mpox cases in the world during the outbreak. California had the highest number of mpox cases in the United States.

On August 4, 2022, the U.S. Centers for Disease Control and Prevention declared mpox a public health emergency in the United States. Wyoming was the last state in the United States to report at least one mpox case. On August 30, 2022, the first mpox death in the United States was reported.