ZEST is a cluster-randomized trial designed to determine whether HIV self-tests are acceptable and improve HIV testing rates and HIV status knowledge among female sex workers in Zambian transit towns. This study will determine whether directly giving participants an HIV self-test or giving them a coupon to collect a test at a drug store or clinic improves outcomes compared to standard of care.

Although Zambia has a generalized HIV epidemic, with approximately 13.3% of adults aged 15 to 49 living with HIV, the epidemic remains even more highly concentrated in key populations, including female sex workers (FSW). A particular concern for FSW is access to healthcare services, including HIV testing services. FSW face significant barriers to accessing healthcare. In other settings, evidence has suggested that stigma is a significant barrier to FSW seeking HIV testing. It is likely that similar mechanisms exist in Zambia. Evidence from Zambia has indicated that complex multilevel factors, such as stigmatization and harassment, contribute to vulnerability among FSW. User-controlled HIV prevention interventions that lead to empowerment of FSW may therefore be a powerful way to address the HIV epidemic in this key population.

Oral HIV self-testing consists of an oral swab kit that allows individuals to test for HIV in the privacy of their own homes whenever they want. The ease of use of HIV self-testing, that it can be done at any time, and that is completely private may make it an attractive alternative to currently-available HIV testing mechanisms for FSW in Zambia. HIV self-testing has generally been shown to be acceptable in a variety of populations, however evidence related to its uptake and acceptability remain sparse, especially among key populations and in Sub-Saharan Africa. This research will provide rigorous evidence of the uptake and efficacy of HIV self-testing for this population.

ZEST was designed to determine whether either direct distribution of HIV self-test kits via peer educators or distribution of HIV self-tests via coupons that participants can use to collect kits at collection points such as drug stores or health posts leads to better coverage of HIV testing and better awareness of HIV status. ZEST is a cluster-randomized trial in which peer educators recruit a small group of FSW participants, and the peer educator group is randomized to one of three study arms: 1) direct distribution of test kits, 2) fixed distribution of test kits, or 3) referral to standard of care HIV testing. The primary outcome is HIV testing in the past month measured at one and four months after the first peer educator visit (when the test kits or coupons are distributed in the intervention arms).

Inclusion Criteria:

• 18 years of age or older
• Female sex
• Reports exchanging sex (including vaginal, anal, and/or oral) for money or goods at least once in the past month
• Self-reported HIV negative with last HIV test at least 3 months OR HIV status unknown
• Permanent residence in the study town of enrollment (Kapiri, Livingstone, or Chirundu)
• Willing to be visited by and meet with assigned peer educator on a monthly basis over the 4-month study period

Exclusion Criteria:

• Less than 18 years of age on the enrollment date
• Has not exchanged any form of sex in the past one month
• Self-reported to be living with HIV
• Self-reported HIV negative status and tested within the past 3 months
• Living in PopART catchment area (Livingstone only)
• Concurrently participating in another HIV prevention study
• Meets criteria but does not wish to participate
• Other

De-identified data will be made available via International Initiative for Impact Evaluation's public access data repository.