First U.S. Case of Aggressive Mpox Strain Detected in California

The U.S. has reported its first case of a more aggressive strain of mpox in a traveler from Eastern Africa, confirmed in California. This strain, clade I, is known for causing more severe disease than the clade II strain that spread widely in 2022. While the strain has been spreading in Africa, there is currently no evidence of its spread in the U.S. The CDC is monitoring the situation, and the U.S. has a supply of the Jynneos vaccine to protect high-risk groups. Health officials believe the U.S. is better prepared for an outbreak than in 2022.