First U.S. Case of Clade I Mpox Confirmed in California

A traveler from Eastern Africa is diagnosed with the more severe mpox strain, but the public risk remains low.

The case marks the first instance of the Clade I mpox strain in the United States, identified in a traveler from Eastern Africa.
The patient, who was treated in San Mateo County, is isolating at home with improving symptoms and is not on specific mpox treatment.
Clade I mpox, known for its severe illness potential, has been spreading in Central and Eastern Africa, but recent cases show milder symptoms with proper medical care.
Health officials are tracing contacts of the patient, though there is no evidence of community spread in California or the U.S.
The World Health Organization has declared Clade I mpox a global health emergency, with over 3,100 cases reported globally since late September.