Authors:

Hetal K. Patel, Yen T. Duong, Sehin Birhanu, Melissa Metz, Jared Garfinkel, Kathryn Lupoli, Daniel Yavo, Herbert Longwe, Faith Ussery, Kristin Brown, Stephen McCraken, Clement B. Ndongmo, Jessica Justman, Andrew C. Voetsch, Bharat S. Parekh for the PHIA Laboratory Working Group

Abstract:

Population-based HIV Impact Assessment surveys were conducted in 14 countries to measure HIV prevalence, incidence, and viral load suppression in children aged 0–14 years and adults aged ≥15 years. We examined the performance of rapid HIV testing algorithms in multiple countries. Survey participants received an HIV diagnosis based on two serial tests in Cameroon, Côte d’Ivoire, Eswatini, Haiti, Kenya, Lesotho, Malawi, Mozambique, Tanzania, and Zambia. Whereas in Ethiopia, Kenya, Namibia, Uganda, and Zimbabwe, diagnosis was based on a tie-breaker algorithm. Testers received intensive training on specimen collection, testing, and results reporting. HIV-positive and indeterminate results were confirmed by Geenius HIV-1/2 test (Bio-Rad). Pooled test 1 and 2 positive concordance, test 2 and 3 negative concordance, and the positive predictive value (PPV) of the algorithm were calculated. A total of 312,069 participants aged ≥18 months (except for Eswatini, Mozambique, and Uganda, where only adults aged 15+ years were included) were tested by either the two-test (n = 243,311) or tie-breaker (n = 98,757) algorithm for diagnosis. The combined test 1 and 2 positive concordance and PPV were 93.8% and 99.4%, respectively, for countries with a two-test algorithm. Similarly, test 1 and 2 positive concordance, test 2 and 3 negative concordance, and PPV were 87.5%, 84.4%, and 98.8%, respectively, for the tie-breaker algorithm. The PPV ranged from 94.2% to 99.9%, with higher PPV in high burden countries. The HIV testing algorithms performed with high accuracy, with PPV reaching 99% or higher. Adoption of continuous quality improvement is essential to ensure accuracy of HIV diagnosis in service delivery settings.