Background:
Persons with acute HIV infection (antibody negative but with elevated levels of detectable HIV virus) are at very high risk for transmitting their infection. Thus, detecting acute infections might be an important HIV prevention strategy.

Objective:
To describe a comprehensive HIV testing program that includes detection of acute HIV.

Method:
All patients at risk of HIV infection are offered confidential HIV testing at the San Francisco municipal STD clinic. Patients initially are tested by either standard (Vironostika HIV-1 Microelisa Enzyme Immunoassay, bioMerieux, Inc.) or rapid ( Oraquick Advance HIV-1/2 Antibody Test, Orasure Technologies Inc.) antibody test methods. Rapid testing is offered to patients with high-risk exposures. HIV antibody negative specimens are tested for HIV ribonucleic acid testing (RNA) (Versant 3.0, Bayer Laboratories) using a one-stage pooling of 10 specimens. Results are available within 10 days. All tests are performed by the San Francisco Public Health Laboratory.

Result:
From December 2003 through October 2005, 6,701 HIV antibody tests were performed, and 5% (n=360) were rapid tests. 2.9% (n=192) of patients refused RNA testing. HIV antibody positivity varied by test type: 3.3% for standard and 7.9% for rapid. 6,271 antibody negative specimens were tested for HIV RNA (5% were rapid antibody negative). Acute HIV infection (antibody-negative/RNA positive) was detected in 0.3% of specimens (0.2% of standard and 1.4% of rapid). Of the 256 total HIV infected persons, 18 (7.0%) had acute HIV infection. The disclosure rates for HIV positive persons were 92% for standard antibody, 100% for rapid antibody and 100% for RNA testing. Ninety-three percent of HIV positive patients were men who have sex with men.

Conclusion:
RNA testing increased HIV infection detection by 7%, and all people were informed of their acute infection status.


Implications:
It is feasible to perform RNA testing in rapid HIV testing settings, including STD clinics.