Q. Can the p24 antigen get detected nine months after HIV exposure?

Answered by
Dr. Arun Kaushik. R
and medically reviewed by iCliniq medical review team.
This is a premium question & answer published on May 04, 2022

Hello doctor,

I am concerned regarding p24 antigen detection. I read in different articles that it is delectable for only two months, and later it disappears as antibodies are formed. The antigen appears again if the person is not being treated. Is it like that? Does the p24 antigen level increase and get detected after nine months if a person is infected but not being treated?



Welcome to

The p24 antigen can be detected faster than antibodies. After two months, as one produces antibodies, the virus will be killed, and the p24 might not be detectable. However, once the antibody level reduces in the body, the antigen can be detected as the viral load increases and the immune cells reduce.

Hello doctor,

Thank you for the reply.

So after nine months, can it be detected again? I am worried about HIV-1 group N and group P. I got an HIV Combo test nine months after exposure, and the technician told me the machine could detect p24 antigen for all groups, including HIV-1 group N and group P. So I wanted to confirm if p24 can be detected nine months after exposure if there is no treatment?



Welcome back to

It depends if you have contracted the infection or not. Yes, the test can detect the p24 antigen if it is present. So if it is negative, it means you are negative.

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