Clade II Mpox Surveillance Update - United States, October 2023-April 2024

Two clades of monkeypox virus (MPXV) are known to cause clade II, which caused a global outbreak starting in 2022. Clade II- associated disease is considered less severe than that of clade I and (1,2). Clade II MPXV continues to circulate at low levels in the United States, but no cases of clade I MPXV have been reported. National mpox case counts peaked at approximately 3,000 per week during late July-August 2022 (Figure), then sharply declined and remain substantially lower than case counts during the peak report summarizes mpox surveillance data reported to CDC durwith federal law and CDC policy.*