A few questions about window periods and HIV testing in general. 

Firstly, my exposure was unprotected oral and genital grinding. No penetration but definitely my penis coming into contact with outer vagina.

Q1. tested negative with early detection PCR test at 25 days. Tested negative at 8 weeks post exposure with combined abs/p24 ag test. Are these conclusive for negative HIV?

2. This week, 11 weeks after exposure I began experiencing flu symptoms. Is this too late for seroconversion? Tested positive for Covid just wanted to make sure Covid lateral flow wouldn’t pick up seroconversion as Covid? 

3. Also tested negative for syphilis by eia igg/igm at 8 weeks, is this conclusive? 

Thanks ! 

You describe a zero-risk sexual event in regard to HIV. Although a few persons have believed they were infected by receiving oral sex, there has never been a scientifically documented case of HIV being transmitted mouth to penis; and the fleeting contact with a partner's outer vagina is risk free as well. (Even with unprotected vaginal sex to completion, the average risk to a male partner -- if the female partner has HIV -- is around one chance in 2,500. And the large majority of even high risk female partners do not have HIV.) In this circumstance, I would have advised against even being tested for HIV. The chance of syphilis was almost as low as for HIV. Finally, your negative test results are conclusive and prove you were not infected.

Those comments cover your questions, but to confirm:

1. By itself, the negative PCR test was at least 99% conclusive; and the AgAb (4th generation) blood tests are definitely conclusive any time 6 weeks or more after the last possible exposure.

2. Yes, 11 weeks is too late for seroconversion. Your covid test was reliable:  there is no interference between covid and HIV tests.

3. There are few data on seroconversion time for the syphilis EIA tests, but all experts consider them conclusive by six weeks. Further, if you had acquired syphilis, you would have experienced an obvious chancre (syphilitic ulcer/sore) on your penis. You can be sure you don't have syphilis.

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

HHH, MD

Me giving oral is also low risk I assume? 

I think I’ve spent too much time reading horror stories online about late seroconversion etc etc 

I think I will do a 12 week blood test as I can do it for free in the UK just for peace of mind but there’s no way you’d expect the results to change? 

Indeed you have to be very cautious in reading online testimony about HIV transmission! You'll be less likely to have problems if you limit searching to professionally run or moderated sites and avoiding those by and for people with various health problems or at risk for them (like reddit, for example).

Of course feel free to test again. You can be sure the results won't change.

Happy new year! 

What are the symptoms of seroconversion and how do they differ from other flu like illnesses. Such as Covid for example.

This is more out of curiosity than anything else. 

That completes the two follow-up exchanges included with each question and so ends this thread. I hope it has been helpful. Best wishes and happy new year yourself!