Screening for Acute Human Immunodeficiency Virus Infection in Baltimore Public Testing Sites

Abstract

Human immunodeficiency virus (HIV) RNA testing of pooled HIV antibody-negative specimens can identify acute HIV infection (AHI) and trigger interventions to reduce transmission during this highly infectious period. A Baltimore, MD program serving sexually transmitted disease clinics and other high-risk sites combined HIV testing by third-generation enzyme immunoassay (EIA) with RNA testing of pooled antibody-negative specimens. Laboratory and Disease Intervention Specialists' records were reviewed for program evaluation. A cost analysis was performed. In 22 months, we tested 60,695 specimens for HIV. Of these, 1766 (2.9%) tested positive by EIA. Pooled HIV RNA testing of 58,925 EIA-negative specimens detected 7 cases of AHI (0.01%). Reflex HIV RNA testing of EIA-reactive, Western blot-indeterminate specimens confirmed 4 additional AHI cases (total AHI, 0.02%). Contact tracing detected no additional previously unknown cases of HIV infection. The utility of pooled HIV RNA testing may be limited by advances in HIV testing technology that reduce the seronegative window period and by characteristics of the local HIV epidemic.