Measuring the burden of undiagnosed HIV infection from a population-based survey in Bukoba, Tanzania: merits of a home-based testing approach Haruka Maruyama 1, Oscar Ernest 1, Sarah Porter 2, Duncan Mackellar 2, Samwel Kikaro 3, Rachel Weber 4, Robert Josiah 5, Deo Mbilinyi 6, Jessica Justman 7, Gretchen Antelman 8 1 ICAP at Columbia University, Dar es Salaam, Tanzania, 2 Centers for Disease Control and Prevention, Atlanta, Georgia, USA, 3 Tanzania Health Promotion Support, Dar es Salaam, Tanzania, 4 CTS Global, Inc., assigned to Centers for Disease Control and Prevention, Dar es Salaam, Tanzania, 5 National AIDS Control Program, Dar es Salaam, Tanzania, 6 Centers for Disease Control and Prevention, Dar es Salaam, Tanzania, 7 ICAP at Columbia University, New York, New York, USA, 8 Elizabeth Glaser Pediatric AIDS Foundation, Dar es Salaam, Tanzania

Background In Tanzania, HIV testing and counseling (HTC) is routinely offered via: – Voluntary or provider-initiated testing at health facilities  benefits health seekers Few studies in Tanzania have evaluated the yield of home-based HTC (HBHTC) on identifying persons with previously undiagnosed HIV infection The Bukoba Combination-prevention Project is a multi-year study measuring uptake and impact of evidence-based interventions, including HBHTC

Objectives Use baseline survey data to investigate: – Patterns of self- reported prior HTC – HBHTC acceptance – Prevalence of prior undiagnosed HIV Location – Bukoba Urban District Contains capital of Kagera Region, bordering Lake Victoria Population: 130, administrative wards; mixed urban and rural in district

Methods Population-based, household survey Selected Enumeration areas (EAs) All households within selected EAs visited Survey participation was offered to all adults aged years. If consented: – Computer-assisted personal interviews on HIV-related risk and prevention behaviors – HTC using the national rapid test algorithm. Data analyzed with SAS 9.3; unweighted results Nov 2013-Aug 2014 Oct 2014-Oct 2016 Nov 2016-Aug 2017

Results (unweighted) 92% contacted households participated (3401/3686) 5,396 persons interviewed: 2,101 (39%) M; 3,295 (61%) F Accepted HBHTC: 89% all (87% M; 90% F) HIV prevalence: 9.1% all (6.1%M, 10.9% F) Undiagnosed HIV prevalence: 5.6% all (4.2%M, 6.4%F)

Results (unweighted) 62% of interviewed participants (52% M, 68% F) reported HIV testing at least once within the past two years Among prior undiagnosed subgroup, 47% (26% M, 56% F) reported they had tested in the past two years Fig 2. Proportion of Previously Known vs Prior Undiagnosed Infection from HBHTC Survey, by sex

Limitations HBHTC was conducted as part of a research study which included participation compensation (e.g., buckets and soap) which might not be replicated in programmatic HBHTC Reported prevalence is unweighted and does not account for our research design Prior HIV diagnosis is self-reported; some previously HIV-diagnosed clients might not have revealed their status (plausibly biasing upwards the percentage of prior undiagnosed of all positives and prevalence of undiagnosed infection)

Conclusion HBHTC acceptance rates were high among both men and women Although nearly two-thirds of interviewed adults reported HIV testing in the prior two years, over half of seropositive adults had undiagnosed HIV – Current HTC practices may not be reaching populations at the appropriate frequency of testing HBHTC is a promising strategy in Bukoba and similar settings in Tanzania to increase HTC uptake among both men and women AND identify those with undiagnosed HIV infection

Thank you! This project is supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) through the Centers of Disease Control and Prevention under the terms of #5U2GPS The findings and conclusions in this [report] are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.