[Question #5674] Testing timeline

19 months ago
Hi Drs thank you for having this forum.       I have a question regarding timeline of 4th generation test .I am testing after having a few protected encounters the last one being this week.I do see you suggest 4th generation test to be conclusive after 6 weeks but I’m wondering if that reliability is because it tests for antigen also how can that be definitive for HIV 2 that it only tests for antibody .I understand that HIV 2is not very common but if I wanted to completely rule that out what test would do that.   Also dies having an autoimmune disorder affect testing timelines.             Again thanks     
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
19 months ago
Welcome fo the forum. Thanks for your question.

Correct that the antigen component of the AgAb (4th generation) HIV tests does not detect HIV2 antigen. But the antibody component detects HIV2 antibody by 6 weeks. The exceptions are sufficiently rare -- and HIV2 sufficiently rare in the US -- that the overall result can be considered conclusive any time 6 weeks or more after the last possibel exposure.

There are no medical conditions -- autoimmune problems or anything else -- that are known to alter the reliability of the current AgAb tests. Although in theory some conditions or medical treatments, like advanced cancer, potent immunosuppressive drugs or cancer chemotherapy, could delay antibody development and thus positive results in an infected person. However, this remains pretty much theory only that actually doesn't happen in real life. And in these conditions the antigen component could be even more strongly positive, and for a longer period of time. To my knowledge, there hve been no reports of false negative AgAb tests in patients with such conditions or treatments.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD
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19 months ago
Hi thank you so much .I know me question is anxiety ridden but I do suffer anxiety what would be a timeline for me if I wanted the total assurance on hiv 2 would it be 10 weeks like the old 3rd gen test
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
19 months ago
The 3rd generation HIV antibody tests are conclusive by 8 weeks, and nearly so by 6 weeks. In any case, since your sexual encounters all have been condom protected, there was little if any risk of HIV. ---
19 months ago
There may have once  that it was unprotected would that change anything 
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
19 months ago
No, doesn't change anything.

That completes the two follow-up comments and replies included with each question, and so ends this thread. I hope the discussion has been helpful. Best wishes and stay safe!
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