Screening yield of HIV antigen/antibody combination and pooled HIV RNA testing for acute HIV infection in a high-prevalence population

Abstract

IMPORTANCE Although acute HIV infection contributes disproportionately to onward HIV transmission, HIV testing has not routinely included screening for acute HIV infection. OBJECTIVE To evaluate the performance of an HIV antigen/antibody (Ag/Ab) combination assay to detect acute HIV infection compared with pooled HIV RNA testing. DESIGN, SETTING, AND PARTICIPANTS Multisite, prospective, within-individual comparison study conducted between September 2011 and October 2013 in 7 sexually transmitted infection clinics and 5 community-based programs in New York, California, and North Carolina. Participants were 12 years or older and seeking HIV testing, without known HIV infection. EXPOSURES All participants with a negative rapid HIV test result were screened for acute HIV infection with an HIV Ag/Ab combination assay (index test) and pooled human immunodeficiency virus 1 (HIV-1) RNA testing. HIV RNA testing was the reference standard, with positive reference standard result defined as detectable HIV-1 RNA on an individual RNA test. MAIN OUTCOMES AND MEASURES Number and proportion with acute HIV infections detected. RESULTS Among 86 836 participants with complete test results (median age, 29 years; 75.0%men; 51.8%men who have sex with men), established HIV infection was diagnosed in 1158 participants (1.33%) and acute HIV infection was diagnosed in 168 participants (0.19%). Acute HIV infection was detected in 134 participants with HIV Ag/Ab combination testing (0.15%[95%CI, 0.13%-0.18%]; sensitivity, 79.8%[95%CI, 72.9%-85.6%]; specificity, 99.9% [95%CI, 99.9%-99.9%]; positive predictive value, 59.0% [95%CI, 52.3%-65.5%]) and in 164 participants with pooled HIV RNA testing (0.19% [95%CI, 0.16%-0.22%]; sensitivity, 97.6% [95%CI, 94.0%-99.4%]; specificity, 100% [95%CI, 100%-100%]; positive predictive value, 96.5%[95%CI, 92.5%-98.7%]; sensitivity comparison, P