Seroprevalence study using oral rapid HIV testing in a large urban emergency department

The Centers for Disease Control (CDC) recommends universal human immunodeficiency virus (HIV) testing for patients aged 13-64 years in health care settings where the seroprevalence is>0.1%. Rapid HIV testing has several advantages; however, recent studies have raised concerns about false positives in populations with low seroprevalence.

To determine the seroprevalence of HIV in our Emergency Department (ED) population, understand patient preferences toward rapid testing in the ED, and evaluate the performance of a rapid oral HIV test.

A serosurvey offered oral rapid HIV 1/2 testing (OraQuick ADVANCE, Bethlehem, PA) to a convenience sample of 1348 ED patients beginning August 2008. Subjects declining participation were asked to complete an opt-out survey.

1000 patients were tested. Twelve had positive results (1.2%), including one who had newly diagnosed HIV infection; 988 patients tested negative. Of these, 335 (33.3%) had never been tested; 640 had prior history of a negative HIV test. No false-positive rapid HIV results were detected; 98.7% received the results of their preliminary HIV test, including 100% of those who tested positive. Most subjects who declined testing cited either a recent negative HIV test (160/348) or low perceived risk (65/348). A minority cited a concern regarding their privacy (11/348) or that the test might delay their treatment (7/348).

The seroprevalence estimate of 1.2% was above the rate recommended by the CDC for routine universal opt-out testing in our study population. The acceptance rate of rapid HIV testing and the percentage of patients receiving results approximated other recent reports.