[Question #6079] HIV test conclusiveness

19 months ago
Hello Doc, thanks for the service.Had a risk event while abroad in Switzerland July 27, 2019. I am a 23 year old white male from the USA and had unprotected vaginal intercourse with a 23 year old white female from the USA. (She had recently been to South Africa btw, that scared me due to their HIV epidemic.) Sex lasted 10 minutes max, I did not ejaculate inside, and I am circumsized. Sex was not super rough and she was not on her period from what I could tell. She does not fit profile of a drug user, she said she tested negative for everything in August, and I was her first encounter since her ex boyfriend in April.

5-6 days after risk event, I developed numerous symptoms. I was not concerned because we were traveling a ton and I have a history of getting sick in close quarters (dorms, hostels, etc.) Symptoms included: 100-102 fever for approx. 10 days, then severe sore throat for about 3 days, had night sweats, chills, moderate fatigue, headache, and swollen lymph nodes in my neck (one was much more swollen than the other and continues to be a little inflamed to this day). I am finally getting over all of these symptoms about 2 months later. Now just the one sort of swollen neck node and a yellowish smelly substance on the back of my tongue that does not scrape away, and sort of gives my mouth a bad taste and makes it feel a little cotton-y.

I went to my doctor when the sore throat came on and had a negative strep test. Then a blood test for Epstein Barr Virus which came back positive and indicated a very recent exposure. Mono was confirmed by monospot. However after reading HIV symptoms online I started to really freak out that it could also be HIV. 

Here are my following test results over the last 9ish weeks:

Oraquick in home antibody @ 21 days = negative

Oraquick in home antibody @ 47 days = negative

4th generation Ag/Ab intravenous lab test w/ Labcorp @ 59 days = negative

Have I tested 100000% conclusively negative for HIV??? What's with the 3 month window period?
Edward W. Hook M.D.
Edward W. Hook M.D.
19 months ago
Welcome to the Forum and thanks for your detailed description.  The short answer to your question is that your tests are absolutely conclusive.  There is no reason for continuing concern or for further testing for HIV related to the encounter you describe.  Having provided you with the "bottom line", let me provide you with a bit more information:

1.  HIV is rare in American women and even if by some chance she had HIV, HIV is transmitted to men through heterosexual genital contact only about once in every 2500 encounters.

2.  Your flu-like illness has been proven to be mononucleosis due to EBV.  FYI, when at risk persons have been studies, less than 1% of persons with the sort of flu-like illness you describe end up having HIV as the cause.

3.  IF your flu-like illness had been due to HIV, your tests would have been positive.  

4.  Your 4th generation test is conclusive.  These tests are entirely reliable any time more than six weeks after an exposure.

Finally, the 3 month window. When HIV tests were just beginning to be available, they tested only for antibodies to HIV and took up to three moths/12 weeks to provide definitive results.  Since then test performance has improved and the 4th generation tests test for both HIV antigen and antibodies to HIV letting them provide conclusive results in 99% of persons 4 weeks after exposure and in everyone at 6 weeks.

I hope this information is helpful. Please don't worry.  EWH
19 months ago
Thank you so much for your reassurance, Doctor. I have had horrible anxiety over this for weeks. Just a few more quick questions!

1) Just to restate, you have never once seen, either in your practice or elsewhere, someone test negative for HIV on a 4th gen lab test past 6 weeks and then turn positive at 3+ months? What factors might extend the window period?

2) I am not sure if my lab test was whole blood or plasma/serum (I ordered it online from lab corp through stdcheck.com, just says HIV 4th generation test). Would this affect the window period or results? The website told me to test again at 3 months for conclusive results. 

3) Is there any cross-reactivity related to acute EBV and HIV that may affect the window period or results?

4) Is there a window within the window period where p24 antigens are undetectable after binding to the antibodies, but there aren't enough antibodies to show up on a test?

Also, have been trying to calculate my odds. I estimated about 300,000 women in the USA have HIV out of an approximated 165,000,000 women in the USA (0.18%). Assuming she had a viral load, my chances of contracting were 29 out of 10,000 according to the CDC (0.29%). And finally, I assumed my test was a false negative 4th gen at 8.5 weeks, a 1.0% chance according to an HIV window period calculator from SmartSexResearch. Together my odds under this scenario would be 1 in 10,000,0000 (0.00001%) of having HIV. Is that a fair assessment?

Thanks again, I really really appreciate it

Edward W. Hook M.D.
Edward W. Hook M.D.
19 months ago
With all due respect, I think your anxiety is getting the best of you.  Straight to your follow-up questions:
1.  Repetitive.  Correct.  The only thing that would extend the period needed for tests to become positive is taking anti-HIV medications.

2.  Your test was almost certainly performed on serum.  Irrespective of whether it was blood, plasma or serum your result would be reliable.  The recommendation for a 3 month follow-up test is overly conservative and unnecessary..

3.  No

4.  This is a theoretical concern which I have never seen or heard of occurring in a person.

I think your odds of being infected are lower than your calculation.  The majority of women with HIV are on therapy and therefore not infectious and the chance that your test was falsely negative is far lower than 1%.

You really need to accept your results.  You did not get HIV from the encounter you described.  Your odds of being struck by lightening are far higher than your odds of having gotten HIV from the encounter you have described.  EWH
19 months ago
Yup got it. I’m going to move on. No reason to doubt modern testing and no reason to doubt some of the best doctors in the field. 

Appreciate the time and the assurance. I can finally get back to my life lol

You may close the thread 
Edward W. Hook M.D.
Edward W. Hook M.D.
19 months ago
Good plan.  You are in the clear.  Glad I could be helpful.  EWH---