Mpox Clade I Has Spread Beyond Africa and Is Now Circulating Locally in Europe. The CDC Expects More U.S. Cases — and the Vaccine Gap Is Getting Harder to Ignore.

More than 20 clade I mpox cases have been confirmed in the U.S. as of June 2026. The CDC now expects additional cases as local clade Ib transmission has been detected in Europe among men who have sex with men with no travel history to Africa. JYNNEOS vaccine uptake lags significantly.