Mpox strain that may be more severe appears to spread locally in U.S. for first time

The first U.S. cases of a potentially more severe form of mpox without known travel were reported in California, health officials said this week.

In a news release Thursday, the Los Angeles County Department of Public Health confirmed an adult is now recovering at home after being hospitalized for a confirmed case of clade I mpox with no recent travel to areas the virus is typically found, primarily in parts of Africa. It was the second clade I case thought to be locally acquired, following a similar report by the Long Beach Department of Health and Human Services , also in L.A. County, earlier this week.

Compared to clade II mpox, which was the cause of the 2022 global outbreak and continued sporadic clusters in the United States, clade I mpox is more likely to cause se