[Question #3021] HIV Testing/Window/Time Test are Conclusive

93 months ago

Good afternoon Doctor,

Regarding HIV testing and timing:

Is it safe to say that a NAT/RNA test alone is conclusive if negative at 28 days?
Or if the NAT/RNA test was combined with the DUO antibody/antigen 4^th generation test and all are negative at 28 days, would this be conclusive?
My local health care department told me the DUO antibody/antigen 4^th generation test would be conclusive at 14 days which I believe to be false.

Thank you.

H. Hunter Handsfield, MD

93 months ago

Welcome to the forum. Thanks for your questions, which are direct and to the point. My replies are similar.

1) Nearly conclusive, but maybe not quite. An antibody test also should be done. The combination of negative NAAT and antibody is virtually conclusive at 4 weeks. However,...

2) ...this combination, antigen-antibody (duo) plus NAAT is absolutely conclusive at 4 weeks.

3) I agree with you; your health department is mistaken, or there was a miscommunication. This test is probably around 70-80% reliable at 2 weeks.

Let me know if anything isn't clear.

HHH, MD

---

93 months ago

Thank you sir. I like the answer to number 2. I'm two weeks out from what you have called a no risk exposure. For peace of mind I would like to put this out of my mind asap. The exposure was a handjob by an Asian prostitute here in the US. She gave me the handjob for 60 seconds until I ejaculated on her hand. Nothing else occurred. She had her panties on the entire time and I didn't notice any blood or fluids from her on me or scrapes or cuts on me. I could have missed something but it would have had to be a small amout. From reading other post this appears to be no risk.

H. Hunter Handsfield, MD

93 months ago

Indeed, there was no risk of HIV from this exposure, even if your partner had HIV -- which, statistically, is very unlikely. I would have recommended against any testing. But you certainly can expect negative results.---

93 months ago

Thank you again for the info. I haven't tested yet as it has only been 14 days. I'll make a decision over the next couple of weeks as to test or not for peace of mind.

For my education, the CDC states:

"Most, but not all people will make enough antigens and antibodies for fourth generation or combination tests to accurately detect infection 13 to 42 days after infection.

Most, but not all people will have enough HIV in their blood for a NAT test to detect infection 7 to 28 days after infection. This is during the time when someone has acute HIV infection."

Who might the "other" people be not included in "most" in the CDC's guidance. Those with immune system issues? My immune system seems to be fine as I tend to heal from cuts, scrapes, and minor colds very well even as of today.

Thanks again.

H. Hunter Handsfield, MD

93 months ago

CDC is providing cover-your-ass legally driven information. The frequency with which "other people" (or anyone) do not develop antibody is virtually zero if not truly zero. And if someone doesn't develop antibody, p24 antigen will always be present, so the duo test will be positive. So in fact, people with "immune system issues" have a greater likelihood of having positive duo test results, not a lower chance.

Don't overthink it. There is no reason for you to believe you might be the exceedingly rare exception to all the rules. In my 30 years experience with HIV testing, I have never seen or heard of a patient who did not have positive results within the time limits we have discussed. Also, in 14 years of doing this and my previous forum at MedHelp, with thousands of questions like yours, not one person ever turned out to have caught HIV. You're not going to be the first. If and when that happens, it will be someone with a real risk, not the sort of zero risks you describe above. You didn't need testing at all and there is no chance you caught HIV.

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

---

93 months ago

Thanks for your time.

H. Hunter Handsfield, MD

93 months ago

You're welcome. I hope the discussion has been helpful. Best wishes and stay safe.---