HIV and hepatitis C virus infection and co-infection among trans women in San Francisco, 2020.

Background: Transgender women (hereafter "trans women") face social marginalization, stigma, and discrimination and experience a high burden of HIV. More recently, trans women have been identified as having a high risk for hepatitis C (HCV) infection. The interaction between these two diseases and the risks for HIV/HCV co-infection among trans women are understudied.

Objective: To characterize epidemiological, behavioral, and socio-structural interactions between HIV and HCV infections among trans women.

Methods: This cross-sectional study examined data from a community-based survey of trans women in San Francisco recruited through respondent-driven sampling (RDS) in 2019/2020. Face-to-face interviews collected data on demographics, medical history, drug injection practices, sexual behavior, and socio-structural factors (e.g., poverty, housing insecurity, incarceration, social support). HIV and HCV antibodies were detected using oral fluid rapid tests and prior diagnosis and treatment were collected by self-report. Blood specimens were collected to confirm antibodies using ELISA. Multinomial logistic regression analysis characterized factors associated with HIV infection alone, HCV infection alone, and HIV/HCV co-infection compared to neither infection.

Results: Among 201 trans women recruited, HIV prevalence was 42.3%; HCV infection by history or current seroprevalence was 28.9%; evidence for both HIV and HCV infection was present for 18.9%. Two-thirds of trans women (67.2%) had been incarcerated; 30.8% had ever injected drugs. History of injection drug use and receiving emotional support from family were factors found in common for HIV infection, HCV infection, and HIV/HCV co-infection compared to no infection. Having a sexual partner who injects drugs was associated with HIV infection alone. Not lacking care due to cost and older age were associated with co-infection. Older age was also associated with HCV infection. Of trans women with HIV infection, 91.8% had accessed HIV care, whereas only 62% with HCV had accessed some form of care.

Conclusions: Our study found high levels of HIV, HCV, and HIV/HCV co-infection among trans women in San Francisco. We found common associations between HIV and HCV through injection practices and emotional support, but having a sexual partner who injects drugs was not associated with HCV infection alone or co-infection. We note a substantial gap in the treatment of HCV for trans women, including those in HIV care, that needs to be urgently addressed.