The first US case of locally acquired clade 1 mpox has been reported in Long Beach, California, according to city and state health authorities.
The clade 1 case is the nation’s first in a person with no recent travel history and the seventh clade 1 case in the country. The patient required hospitalization and is now isolating and recovering at home, the City of Long Beach news release said.
Public health officials are reviewing the patient’s potential source of exposure and conducting contact tracing. No other cases have been identified.
“While the overall risk of mpox clade I exposure to the public remains low, we are taking this very seriously and ensuring our community and health care partners remain vigilant so we can prevent any more cases,” Long Beach Mayor Rex Richardson said in the release. “This underscores the importance of continued surveillance, early response, and vaccination.”
Clade 1 primarily found in Africa
Historically, clade 1 is tied to more severe illness and has mainly been found in Central and East Africa. Clade 2, which usually causes mild illness, was linked to the large 2022-23 mpox outbreak in the United States and elsewhere that was spread primarily in men who have sex with men (MSM). Mpox symptoms can include rash or sores, fever, chills, sore throat, swollen lymph nodes, and body aches.
Anyone with an unexplained rash or lesions should seek care promptly.
The first US clade 1 detection was also in California, in November 2024. It, like the other five US clade 1 detections before the Long Beach case, involved travel outside of the country.
Mpox spreads through direct contact with infectious sores or body fluids, sexual or intimate contact, and touching contaminated items such as clothing or bedding.
The Centers for Disease Control and Prevention (CDC) recommends vaccination with Jynneos for people at high risk of exposure, including those who are gay or bisexual, MSM, transgender and non-binary people, those with weakened immune systems (eg, with HIV), people exposed to an infected person, those with occupational exposure, and those planning to travel to areas with ongoing outbreaks.
A booster dose isn’t recommended for people who have completed the two-dose series. Most mpox patients recover within 2 to 4 weeks without treatment.
“Anyone with an unexplained rash or lesions should seek care promptly,” Cliff Okada, MD, Long Beach public health physician, said in the release. “Speak openly with intimate partners and your healthcare provider. Early action protects you and others.”