Southern California Reports Three Clade I Mpox Cases

The Los Angeles County Department of Public Health (LACDPH) recently confirmed its first case of clade I mpox in an adult with no recent travel to regions where this virus is typically found. The individual was hospitalized and is now recovering at home.

This is the second clade I mpox case in LA County and the second in the nation without known travel to another country where clade I is typically found.

The City of Long Beach also announced a separate clade I mpox case this week.

As of October 16, 2025, LACDPH is collaborating closely with the California Department of Public Health and the U.S. Centers for Disease Control and Prevention to investigate these mpox cases as swiftly and effectively as possible. Enhanced surveillance and contact tracing are underway to identify any additional cases and potential sources of the infection and to prevent further transmission.

Two clades of the mpox virus cause Mpox: clade I and clade II. Both clades may present with flu-like symptoms followed by a rash, and can be spread through close person contact (sex, massage or cuddling) and within households or by sharing personal items.

So far in 2025, LACDPH has reported 118 cases of clade II mpox.

"The identification of cases of clade I mpox, which may cause more severe illness than the more common clade II, is concerning," said Muntu Davis, MD, MPH, Los Angeles County Health Officer, in a press release. 

"Mpox continues to be spread largely through close, intimate contact with symptomatic people, mainly during sexual activity. Early detection, testing, and vaccination are vital to controlling the spread of this virus."

"Getting both doses of the JYNNEOS® (MVA-BN®, IMVAMUNE®) vaccine provides the best protection against mpox."

This Mpox vaccine is offered at various clinics and pharmacies in the USA.