Missed opportunities for PrEP among the partners of people newly initiated in HIV care in western Tanzania

Introduction: Pre-exposure prophylaxis (PrEP) has the potential to significantly reduce incident HIV globally, especially among individuals in sero-discordant partnerships with repeated HIV exposure and/or whose partners are not virally suppressed (undermining “Undetectable = Untransmittable”). Partner-based referrals may enhance PrEP uptake, yet data on PrEP awareness and willingness among people living with HIV (PLHIV) in east Africa is limited. We assessed PrEP knowledge and willingness to support partner uptake of PrEP among antiretroviral therapy (ART) initiates in Tanzania. Methods: Data were from the Afya II cluster RCT, which recruited ART initiates (n=1,990) randomized to usual care or monthly cash incentives for clinic visits. At the twelve-month visit, participants completed a sub-section on PrEP knowledge and attitudes, partner PrEP use, and understanding of U=U. We used multivariable regression to analyze correlates of U=U agreement (linear) and PrEP awareness (logistic). Results: Over half (59%) of participants had never heard of PrEP and 52% were in sero-discordant relationships. Among those in sero-discordant relationships, 22% reported their partner PrEP use. Participants showed high support for partner PrEP use (70% very supportive). Median U=U agreement was high (4.0/5.0). Female sex was associated with higher U=U concordance (β=0.84, 95%CI: 0.73-0.97). Among those in sero-discordant relationships, PrEP awareness was higher among those with greater education (AOR=2.91, 95%CI: 1.21-6.98). Conclusions: PrEP awareness was low despite over half of participants being in sero-discordant partnerships. Ensuring PrEP promotion during routine HIV care visits, particularly among ART initiates who have yet to achieve viral suppression, may support secondary prevention of HIV efforts. Clinical Trial Number: NCT04201353