San Francisco STDs Drop 24% Thanks to New Prevention Tool

San Francisco is celebrating a major public health victory after reporting significant drops in sexually transmitted infections across the board in 2025.

The city saw syphilis cases plummet 24%, chlamydia decline 18%, and gonorrhea fall 5% compared to 2024. These aren't small numbers when it comes to public health.

The secret weapon? A treatment called doxycycline post-exposure prophylaxis, or doxy-PEP for short. It works simply: people take a dose of antibiotics after sex to prevent certain bacterial STIs before they take hold.

San Francisco broke new ground in 2022 by becoming the first public health department in the country to issue guidance on doxy-PEP. That early leadership is now paying off in real numbers.

The biggest improvements came among men who have sex with men and transgender women, communities that have historically faced higher infection rates. This matters because it shows targeted prevention can work where it's needed most.

Dr. Stephanie Cohen, who directs STI and HIV prevention for the San Francisco Department of Public Health, credits years of research and coordination across the city's health system. The work didn't happen overnight.

The Ripple Effect

San Francisco's success is already influencing sexual health approaches nationwide. Earlier research from the city and Kaiser Permanente Northern California proved doxy-PEP's effectiveness, giving other cities a roadmap to follow.

Health officials are quick to note that no single tool solves everything. They're encouraging people to keep up the momentum with regular testing, vaccination, and open conversations with partners and healthcare providers.

The timing matters too. While San Francisco's numbers are dropping, STI rates have been climbing nationally for much of the past decade. This shows that targeted, science-based interventions can reverse worrying trends.

Testing and treatment remain available through city clinics and other programs, including for people without insurance. Accessibility has been key to the program's success.

Health officials released the data during national Sexually Transmitted Infection Awareness Week, offering hope that what works in San Francisco can work elsewhere too.