Can PEP treatment prevent HIV showing up on a blood test?

[Dm123456]

I had unprotected vaginal sex with a sex-worker and 7 days later went for an antibody/antigen HIV test, which came back negative.

I started taking tenofovir and rilpivirine meds at this point (this is very late and I was not prescribed them) and took a qualitative HIV PCR test 2 days later (9 days post-exposure) which came back negative.

However, my lymph nodes around my neck, behind my ears, inside elbows, upper arms, groin and behind my knees are all very warm to the touch and my forehead is constantly hot. My temperature is running at about 37.5 degrees. Also, my throat is a little sore and I have a mild dry cough. This has been ongoing now for almost a week.

My questions are: Is it possible the PEP meds prevented HIV showing up in my blood on the PCR test? What can I do now to test for HIV? And how soon can I find out?

Also I intend to stop taking the PEP 28 days from my first dose (as usually recommended).

Thanks.

[Dm123456]

UPDATE: The CSW I had a high-risk exposure with had a negative Anti-HIV test at 19 days and a negative HIV Ag/Ab Duo test at 5-6 weeks.

My HIV Ag/Ab Duo at 36 days post-exposure was negative. NAAT test at 40 days (1 week post PEP) was negative.

Will re-test in August to make absolutely sure, although the specialist said the NAAT test is 100% confirmation.

[kapster1978]

Firstly, did you speak with care taker at std testing- about possible pep meds? 48hours is recommended and latest is 78 hours. But the likehood it works from near 78hours is low. So if you take the meds 7days after expoture it's really no use anymore. But that aside, to answer your question. Yes the meds for pep are supressing the virus and when taken very early after expoture it gives a chance to suppress so much that the virus can't get hold in the body. Therefore it can influence testing and is testing 4 weeks after stopping meds advised for 4th gen and 12 weeks for conclusive. But this all aside, if you didn't have a wound on your penis and you didn't notice blood from the vagina the chance of contracting hiv is low. Also if you don't know the status of that sex partner it will even lower your chance for hiv. If she would have hiv the chance is 1:2000 if circumized and if not 1:1000.  Also most csw don't have std's as they are checked often, only drug addicted csw are higher risk to have std's. Therefore I think the chance you have hiv is low, but not zero. For other std's the chance is much bigger.(chlamydia, gonnnoroe)

[Dm123456]

Thanks for your answer. So after 2 days, the PEP meds could have suppressed the virus enough to cause the negative PCR test result? Or would there still be an amount of detectable HIV RNA? I know there's a lot factors at play..

I read the virus hides itself in places like the lymphatic system when under attack from ART meds, making it undetectable in blood.

Is there anyway I can gain more clarity about my status at this point through HIV testing? Sorry for the questions and thanks for any help.

[kapster1978]

It could. But way did you start with PEP and especially so late? Most std doctors wouldn't suggest to do pep with vaginal sex. Only when it's sure the partner has hiv. Therefore you can see that the chance for you to get hiv in the first place wasn't huge. For conclusive answer hiv, you now need to do testing 4th gen duo 4 weeks after stopping meds and conclusive after 12 weeks.(most doctors would say it's conclusive after 4 weeks. But unproted vaginal sex gives highest risk for gonnoroe and chlamydia.

Ps self medication is really not recommended because possible side effects. Especially with pep the combinations need to correct and has heavy effect on your health. In my country it even would not be possible to get the meds without a doctor sub recommends it.

[Dm123456]

I got PEP from someone who was prescribed it before.. which was stupid. The HIV specialist I saw today told me the meds I'm on wouldn't affect an NAT test.. and he reiterated your point that vaginal sex is lower risk.

So I'm no closer to understanding what that PCR test meant.. some sources say PEP can cause a false negative.. and the doctor told me the opposite..