Can A 4th Generation HIV Ab/Ag Test Help In Detecting HIV 2?

Posted on Mon, 25 Jan 2016

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Mon, 25 Jan 2016 Answered on

Thu, 25 Feb 2016 Last reviewed on

Question : Dr. I just forgot to mention that the 4th generation ab/ag test on 34th day was both HIV1 and 2. Should I consider it conclusive for both HIV1 and 2?
Thanks alot.
Please refer to my original question today which you were very kind to reply:

Answered by Dr. Dr. Kakkar (26 minutes later)

Brief Answer:
Hiv 2 is rare but can be reliably excluded by Ab testing at 12 weeks

Detailed Answer:
Hello. Thank you for writing to us

I have gone through your query and I have also reviewed your previous query.

A negative Hiv ag/ab test beyond 4 weeks reliably rules out Hiv 1 however Hiv 2 which is itself very very rare can only be excluded reliably by an antibody based test at 12weeks. Ag/ab test does'nt include testing for Hiv 2 antigen therefore this test for hiv 2 detection has a longer window period i.e 12 weeks as antibodies might take longer to appear. However hiv 2 is itself very very rare.

Regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar