Background The November 2018 U.S. Preventive Services Task Force draft statement recommended clinicians offer HIV pre-exposure prophylaxis (PrEP) to women with recent syphilis (all stages) or gonorrhea diagnosis. We estimated HIV incidence among women in King County, WA following syphilis or gonorrhea diagnosis, and attempted to identify risk factors for HIV acquisition that might prompt clinicians to offer PrEP.

Methods We matched public health HIV and sexually transmitted infection (STI) surveillance data for 2008–2018. Incidence rate was calculated using person-years (py) of follow-up, defined as time from initial STI diagnosis date to either HIV diagnosis date or end of study period. Women with prior or concurrent (within seven days of STI diagnosis) HIV diagnosis were excluded. Risk factors were identified from disease intervention specialists (DIS) interviews.

Results Between 2008–2018, 5,524 and 397 King County women were diagnosed with gonorrhea and syphilis, respectively. Over 1,705 py (median: 3.8) of follow-up, no incident HIV diagnoses occurred among women diagnosed with syphilis. Among women diagnosed with gonorrhea, 16 incident HIV diagnoses (incidence 0.06/100 py) occurred over 24,758 py (median: 3.7). Median time from gonorrhea to HIV diagnosis was 1.7 years (IQR: 0.5–3.0). DIS interviewed four (25%) of the incident diagnoses following gonorrhea diagnosis; two (50%) had risks identified: both reported injection drug use (IDU), sex with a person who injected drugs (PWID), and methamphetamine use. DIS interviewed eleven (69%) of the women following HIV diagnosis; nine (82%) reported at least one of following: IDU, methamphetamine use, exchange sex, or serodiscordant, bisexual, or PWID sex partners.

Conclusion HIV incidence among King County women with gonorrhea and syphilis appears to be low. Although these diagnoses do not clearly identify a population that would benefit from the draft PrEP recommendations, the generalizability of these findings is uncertain and additional data on HIV incidence among women following bacterial STIs are needed.

Disclosure No significant relationships.