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please advise


i had an unprotected anal sex with a gay ( me insertive partner) whose status unkown . i had a p24 antigen antibody test negative at 39 days and 67 days after exposure .Is my result conclusive or i need to retest again at 84 days .Please advice



Thank you for your inquiry. From what we gather from the question, you were asking about the conclusiveness of the P24 Antigen test, after performing unprotected anal intercourse. From the information given, this scenario is determined to be High Risk because it involves the exchange of body fluids (Evidence of transmission through these activities and is the majority of cases of transmission)

In order to contract HIV the following conditions must be met: There must be HIV present in a bodily fluid. The five bodily fluids that carry the HIV virus include: blood, semen (including pre-ejaculate), vaginal fluids, breast milk, and rectal secretions. The bodily fluid containing HIV must have direct access to the bloodstream. This can be through cuts, tears, rips, mucous membranes, open sores, or needles. Transmission occurs through a risky activity in which the first two conditions are met. For example: condom less sex, sharing needles, unsafe tattoos or piercings, vertical transmission–from mother to child (in utero, during delivery, breastfeeding).

If you are continuously engaging in high risk activity there are biomedical approaches such as PrEP (pre exposure prophylaxis) and PEP (post exposure prophylaxis) that help lower your risk of acquiring HIV.

P24 Antigen Test: The antigen portion of the test is detectable immediately after infection (3-4 days post exposure) for the first 2-4 weeks. The Antibody portion of the test is detectable from 3-4 weeks on wards. Many HIV specialists consider this test conclusive at 6 weeks. At 6 weeks it is considered 99.9% accurate. Official guidelines recommend re-testing at 12 weeks with an antibody test. Since your tests were negative at 39 and 67 days they are considered to be accurate. However, the Official guidelines do recommend retesting at 12 weeks therefore, you can get re tested at day 84.

Recommendation: Refer to Physician for HIV test.

Regards, AIDS Vancouver Helpline/Online, (Vardah)