Dear Dr. Holodniy,

Four weeks after a risky sexual exposure (unprotected oral sex), I experienced many of the symptoms associated with acute retroviral syndrome. These symptoms included a persistent sore throat, swollen glands, stiff neck, and night sweats. I participated in a research study based in Los Angeles designed to identify HIV infection at an early stage. The tests conducted on my blood were a P24 antigen test, HIV antibody tests (Elisa and Western blot), and a QHIV by bDNA viral screen. All came back negative. My symptoms lasted two more weeks then gradually faded. I'm concerned that the tests may simply have been too early to detect infection. How soon after infection will a viral load test show the presence of the virus? Thank you for the service you provide!

Viral load tests have been shown to be positive within several days to a couple of weeks after exposure/infection. Antibody and western blot assays can be negative or indeterminate for a few weeks after infection. P24 antigen will be strongly positive within days to a couple of weeks after infection. However, unlike viral load, p24 will usually disappear fairly quickly. I strongly recommend retesting as a followup.

MH