Real-time, Universal Screening for Acute HIV Infection in a Routine HIV Counseling and Testing Population

CONTEXT: Acute human immunodeficiency virus (HIV) infection cannot be diagnosed by routine antibody tests and is rarely diagnosed in clinical practice. However, HIV nucleic acid-based testing is widely used to screen for antibody-negative acute infection among low-risk blood donors. OBJECTIVE: To assess the feasibility of screening in high-volume laboratories for acute and long-term HIV infection in a routine HIV testing population, in which HIV infection prevalence is low, using specimen pooling and HIV RNA reverse transcriptase-polymerase chain reaction (RT-PCR) tests. DESIGN AND SETTING: Clinical diagnostic performance evaluation at a state-funded public health virology and serology laboratory. PARTICIPANTS: A total of 8505 consecutive individuals presenting for routine HIV counseling and testing during a total of 20 business days to simulate a month of testing in August and December 2001 at 110 publicly funded testing sites in North Carolina. MAIN OUTCOME MEASURES: Prevalence of acute and long-term HIV infection. Serum specimens negative by HIV enzyme immunoassay (EIA) were screened in pools by an ultrasensitive HIV RNA RT-PCR test. Results for individual HIV RNA-positive specimens were reclassified as true or false according to results of confirmatory testing. RESULTS: Of the 8505 individuals screened, 8194 had not previously tested HIV positive and had sufficient serum to complete the testing protocol. Of those, 39 had long-term HIV infection (prevalence, 47.6 per 10,000 at-risk persons 95% confidence interval, 33.8-65.0 per 10,000). Of the 8155 at-risk individuals whose antibody tests were negative, 5 were HIV RNA positive. Four of those had true-positive acute infection (prevalence, 4.9 per 10,000 95% confidence interval, 1.3-12.5 per 10,000). All 4 were women; 2 developed symptoms consistent with an acute retroviral syndrome in the week after testing. Screening all specimens required 147 HIV RNA tests. Overall specificity of the strategy was 0.9999. CONCLUSIONS: These findings suggest the widespread diagnosis of acute HIV infections in a routine testing population is not only possible but feasible using specimen pooling and nucleic acid testing. These additional procedures may increase diagnostic yield by approximately 10% compared with conventional HIV antibody testing.