Mpox in Alameda County
Information on MpoxMpox Updates (September 3, 2025)
There has been a recent increase in mpox in Alameda County, as well as other areas in the San Francisco Bay Area (see CDPH Health Advisory). In Alameda County, we have had a 4-fold increase in mpox cases since July 2025.
Mpox is characterized by a diffuse or localized rash; the rash can be preceded by a prodrome or other symptoms in some people (see CDC Clinical Features of Mpox). Mpox is usually transmitted by close and sustained physical contact. Mpox has two clades, Clade II was the cause of the large global outbreak in 2022, and is still circulating. Clade I mpox is primarily occurring outside the United States. Both clades are prevented by JYNNEOS vaccine (mpox vaccine). One dose of the vaccine has 36-75% efficacy, and two doses has 66-89% efficacy for prevention of mpox (see JYNNEOS Vaccine Effectiveness).
Providers should:
- Test for mpox when a patient presents with new rash and other symptoms (see Compatible Signs and Symptoms).
- Recommend mpox vaccination for persons at risk , and a second dose for anyone who has not completed the 2-dose series. Getting more than 2 doses (“booster”) is not recommended. In Alameda County, anyone who thinks they need the vaccine should get it.
- Vaccines are available at many chain pharmacies and certain clinics—see Mpox Vaccine Locator. JYNNEOS (mpox) vaccine will also be available with limited supply at Oakland PRIDE, Oakland LGBTQ center, and Steamworks (9/5, 9/6, 9/9).
- Ensure persons know the signs and symptoms of mpox illness so they are evaluated and tested in a timely way if they are symptomatic.
- Submit a confidential morbidity report (CMR) to Alameda County Public Health Department for suspect and confirmed cases of mpox that reside in Alameda County.
- Ask about planned travel and recommend mpox vaccine for those at risk.
- For persons with suspect mpox that have had recent travel to specific locations or contact with someone with known mpox clade I, test for mpox Clade I. Contact Alameda County Public Health Department at sexualhealth@acgov.org and follow the procedures for testing for Clade I mpox by sending the test to the Viral and Rickettsial Disease Laboratory (VRDL).
Mpox — pronounced /m·pox/ — is formerly known as Monkeypox. Mpox is a rare disease that is caused by infection with the Mpox virus. Mpox can cause fever, headache, body aches, swollen lymph nodes, and a rash. The rash typically begins as flat spots that turn into bumps that fill with fluid. Some people develop spots that look like pimples or blisters before having any other symptoms. The bumps eventually crust and fall off as they heal.
The Mpox virus is not new, but there is a recent significant increase in reported cases where Mpox is not commonly seen, including in the United States, California, and Alameda County.
While it’s good to stay alert about this new local epidemic, the current risk of Mpox for the general public is low.
To learn about preventing infection, visit our FAQs webpage. If you are experiencing symptoms or were exposed to someone who is suspected or confirmed to have Mpox , contact your health care provider right away to be connected to testing, and vaccine or treatment. If you don’t have a health care provider, email monkeypox@acgov.org.
Signs & Symptoms
What to look for if exposed to Mpox
Isolation Guidance
Stay home if you test positive for or have symptoms of Mpox
State Guidance
CDPH guidance and resources on Mpox
Federal Guidance
CDC guidance on the national Mpox epidemic
Mpox Graphics
Visual examples of the Mpox rash
Have a Question about Mpox?
Contact us at 510-268-2101 for answers to your questions about Mpox, including how to access vaccine or treatment.