[Question #9612] HIV Concerning

30 months ago

Hello Doctors

I live in Barcelona, and 9 weeks ago I had protected oral and anal sex with a russian woman from an expensive brothel (we used the same condom). The condom seemed ok when we finished. As many of other clients here in the forum, HIV became the main concern after this encounter. As a result, I got (over) tested:

1) 10 days after the encounter: PCR Negative
2) 14 days: PCR Negative
3) 21 days: PCR Negative
4) 28 days: 4th gen test lab/PCR Negative
5) 47 days: 4th gen test lab/PCR Negative
6) 57 days: 4th gen test lab Negative

My questions are:

1) Can I finally move on and leave this behind? Should I concern for HIV-2? (Some say it may take 12 weeks to have a conclusive result for both types of HIV, especially for HIV-2)

2) Do condoms offer full protection in a single act? There's a study cited by the CDC that the consistent and correct use of condoms reduce the risk by 80% https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6195215/
3) When I took the last exam I had 4 days taking Amoxicilina and Enantyum. Can this affect the so-called window period for this test?

4)Between week 8 and 9 after the encounter, I had symptoms similar to a common cold (stuffy nose, dry cough, mild sore throat). My rational mind tells me it's only a cold, but my anxiety wonders if it's related to "delayed seroconversion", because my roomates don't have the same symptoms.

My problem is that I tried to manage this by myself and have spent too much hours reading about the topic and I'm really confused now. I tried to stick only to official sources, but it's impossible when anxiety kicks in.

I just want to leave this behind and stop thinking about it each day. It's exhausting. With your help and knowledge, I hope I can.

Thanks

H. Hunter Handsfield, MD

30 months ago

Bienvenido al foro y gracias por su confianza en nuestros servicios.

You describe a completely safe exposure. Condoms work, so you were well protected. If you had asked before now, I would have advised that no testing was needed. And I agree with your own statement that you were over tested for HIV. Even if you knew your partner had untreated HIV with a high viral load, the negative test results you report are conclusive. You could have stopped after the combination of negative PCR and antigen-antibody (AgAb, 4th generation) at 28 days.

Those comments pretty well answer your questions, but to be explicit:

1. No responsible and knowledgeable expert believes or advises waiting as long as 3 months for conlucsive results with the AgAb tests. Negative results always are conclusive at 6 weeks (officially 45 days). That includes HIV2; but anyway, HIV2 is nearly absent in most industrialized countries (although I do not know the data for Spain).

2. The 80% estimate for condom effectiveness against HIV is the average over time for multiple uses by large numbers of people. Such estimates include mistaken reporting, errors in condom use, and breakage. Condoms are 100% effective, or close to it, for any single exposure with proper use with a condom that does not break.*

3. There are no medications or medical conditions that alter the reliability or timing of HIV test results. None, including amoxicillin and non steroidal anti-inflammatory drugs like Enantyum.

4. HIV test results overrule all symptoms. It is not possible to have HIV symptoms with a negative antibody test; your results prove HIV was not the cause of the symptoms you describe. In addition, they occurred much too long after exposure to be caused by ARS. Finally, ARS does not cause nasal congestion or cough.

Anxious persons are easily drawn to information that confirms their fears, missing the reassuring information. In the US, there is a somewhat famous statistician named Nate Silver (see https://fivethirtyeight.com/). He wrote a book about how statistics, "The Signal and the Noise". In it he writes (approximate quote) "Give an anxious person a computer with an internet connection in a dark room, and soon he will believe his common cold is bubonic plague." Does that sound familiar? I suggest you stop searching, or at least be careful!

* Interesting that you cite this particular source. in addition to the condom estimate, it provides estimates on the risk of HIV from entirely unprotected sexual encounters with infected persons. It's the main source we use on this forum for such estimates. For unprotected vaginal sex with an infected (and untreated) female, HIV is estimated to be transferred about once for every 2,500 episodes of unprotected vaginal and once for every 1,000 exposures by insertive anal sex. (See Table 1.) That's only with a known infected pattern and without a condom. If we assume a 1% chance your partner had HIV, these risks become 1 in 250,000 and 1 in 100,000, respectively. So even before considering condom use, there was almost no chance of HIV from the events you are concerned about. (Do you see what I mean about online information? You focused on 80% condom effectiveness, but not the low chance of sexual exposure even without condoms!)

The bottom line is that you can stop worrying about HIV. You were at little risk to start and you do not have HIV.

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

HHH, MD

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30 months ago

Thank you for your clear responses, Dr Handsflied (Excellent Spanish, btw). If you don't mind, I have a couple of more questions/comments:

1) Could please explain why the combination of PCR/4th gen test is considered conclusive at 4 weeks? It was my little understanding that 33 and 45 days were necessary to "capture" 99% of HIV-1 infections, respectively.

2) My confusion for HIV-2 window period comes from 2 paper/documents that I read. One from Sweden authorities (https://pubmed.ncbi.nlm.nih.gov/26414596/) and from UK authorities (https://www.bhiva.org/file/6089146990eff/HIV-2-guidelines-consultation.pdf). They both state that the window period for HIV-2 may be 12 weeks/3 months. Would say they are being overcautious about it or is it because the 4th gen tests work as a third gen test for HIV-2, given it does not detect HIV-2 antigen? Anyway, in Spain there are less than 500 cases reported and the majority are people from endemic regions or people who have travelled there. So, as you said, we can pretty much discarded.

Anyway, muchas gracias por su ayuda, Dr. As you said, we, the anxious people, tend to convince ourselves of the worst case scenario even when everything points out to the contrary. I guess it is time to move forward, get out of my room and have a life again.

H. Hunter Handsfield, MD

30 months ago

Thanks for the comment on my Spanish. (I did it myself, not a translate program; I studied it 5 years and am reasonably fluent.)

1) Simple statistical principles: each test (PCR, AgAb) is ~99% conclusive at 4 weeks, i.e. 1% of infections missed. The combination misses 0.01 x 0.01 = 0.0001, i.e. one in 10,000 infections. Then add the low risk of transmission discussed above, i.e. one chance in a thousand for insertive anal sex. So even with a proved infected partner the chance you have HIV with those test results is 0.0001 x 0.001 = 0.0000001, i.e. one chance in a million. If we then add a 1% chance your partner has HIV, it's one in 100 million. Zero.

2) My understanding is that the third generation antibody tests (including the antibody component of the AgAb tests) detect all HIV2 by 8 weeks. And the same principles above apply here as well: the low chance your partner had HIV, low transmission risk if she did, and the rarity of HIV2 in most industrialized countries; multiply the test performance figures and it would come to under one chance in a billion you have HIV2 after your negative tests results. In other words, zero. (The data you found on HIV2 in Spain is in nearly exact agreement with the situation in the US.)

Indeed you can "get out of [your] room and have a life again." Bienvenido de vuelta al mundo!

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30 months ago

Hello doctor

I was reviewing some emails from past weeks and I realized I never replied to you. First of all, thanks for the valuable information and advice. Getting out of my room was really helpful and it helps to see things more clearly and rationally. Maybe I can use my last follow-up question to ask you about other tests I took and safe practices:

1) On day 28 I took a gonorrhea and chlamydia test and on day 47 I took a syphilis, Hepatitis B and C test (I know from your replies in other questions that Hep C is not considered a STD, but it was included in the package). The results were negative. Are these results conclusive given that the sex was safe (despite it was with a CSW)?

2) Besides condom usage and wise partner selection, do you have another advise for safe practices? (Maybe testing more regularly and discussing sexual health before?)

Anyway, thanks for your help and again, very impressive Spanish!

H. Hunter Handsfield, MD

30 months ago

1) Yes, those test results are conclusive.

2) Periodic testing is indeed a wise practice, although the frequency of course depends largely on the frequency of potentially high risk exposures. If events like your Barcelona adventure occur say once a month, perhaps routine testing every 6 months would make sense. Less frequent exposures, maybe test once a year. I would limit such testing to urine for gonorrhea/chlamydia and blood tests for HIV and syphilis. Those probably will cost less than larger "comprehensive" panels, and you really don't need testing for viral hepatitis, HSV, etc, unless maybe once every 10 years or so.

That concludes this thread. Thanks for the thanks -- I hope these final comments also are helpful. Mis mejores deseos y mantente seguro.

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