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What is the accuracy of p24 test? Had protected sex relationship with multiple women. Chances?

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hi doctor i want to ask about accuracy of p24 (combo) test it is negative in day 40 from protected sex relation with 3 womens and also i have oral sex ?
i have also negative antibody test in day 39
why i wait to 3 months as i am very very depressed and i want to be comfort
Posted Tue, 8 May 2012 in HIV and AIDS
Follow-up: What is the accuracy of p24 test? Had protected sex relationship with multiple women. Chances? 4 hours later
what about my next test is it better to take another p24 combo test or elisa antibody test in day 60?
Answered by Dr. Rohit Batra 18 hours later
Thanks for posting your query!

P24 is an antigen test and usually gets positive within 7 days of unprotected high risk behavior.
If the antibody test is negative at day 40, it can't be a definitive test as the antibodies are not detectable between 3 weeks to 3 months. This happens as the antigens start combining with the antibodies.
A repeat antibody test needs to be carried out at an interval of 3 months after exposure as it's at that time that antibodies get excessive and are detectable.

So I would advise you to wait for 3 months and get an antibody test done. There is no need to get the combo test repeated.


Dr.Rohit Batra
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