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TheBugDoctor, Doctor (MD)
Category: HIV and AIDS
Satisfied Customers: 1664
Experience:  I am a Board Certified Infectious Diseases physician with many years experience treating a broad range of infectious diseases.
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intercourse..HIV Positive..weeks post exposure, it came back negative

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I had intercourse with someone one time who I learned after was HIV Positive. I am female he is male. Since the exposure, I hade a P24 Antigen test at two weeks post exposure, it came back negative. What is the liklihood that my ELSA test will also come back negative at the three month mark? How accurate is P24? It there a strong chance that i may still be positive?



The risk of infection depends on a number of things- including the viral load ( quantity of virus) that the guy had, what specific activities you engaged in ( oral, anal sex etc), use of condoms, exchange of fluids/ blood, etc. Even still, the risk from having sex on one occasion, is still fairly uncommon- like 1 in 1000 for penile/vaginal intercourse.


We rarely do check the p24 test in the United States as it is not as accurate as other more standard tests ( ELISA and PCR). While it may be positive early after infection ( within a few weeks) I would not rely on its results one way or another.

I would recommend ELISA and Western Blot testing at 1 and 3 months after your exposure.


Good luck.


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