Targeted approaches for acute HIV infection diagnosis in rural Eswatini

IntroductionAcute HIV infection (AHI) diagnosis is challenging due to complex diagnostics and low prevalence. We tested different targeting approaches for AHI testing using data from a cross-sectional study of STI burden in Eswatini.MethodsFrom June 2022 to April 2023, adults underwent routine HIV and viral load (VL) testing (Xpert) and completed a questionnaire on socio-demographics, behavioral characteristics and current symptoms. AHI was defined as negative/discordant serial HIV rapid diagnostic test and VL ≥10,000 copies/mL. We used lasso regression to determine risk factors for AHI and build study-specific predictor risk score (PRS). We evaluated the ability of the PRS and other targeting approaches to predict AHI.ResultsOf 1064 participants, ten (0.9%) had AHI. The 10-parameter PRS at cut-off ≥10.8 had the area under the curve (AUC) 0.87 (0.86-0.89), sensitivity 100% (69.2-100), and proportion needed to test (PNT) 26.1%. At the cut-off ≥14.1 the AUC was 0.85 (0.71-0.98), sensitivity 80% (44.4-97.5) and PNT 11.5%. A previously developed PRS and targeting young women reporting AHI symptoms also performed well, but not the WHO-recommended clinical screening criteria for AHI (sensitivity 40%).ConclusionsTargeted approaches that combine AHI symptoms and locally relevant characteristics may be an efficient way to support the scale-up of AHI testing.