[Question #701] Unprotected Sex with Escort

101 months ago

Hello Doctors,

I had an unfortunate experience two days ago. I’m a 65 year old man in California and I had vaginal sex with a female escort. The condom came off without either of us realizing it. So I was unprotected for a few minutes. There was no ejaculation. The escort says she tested negative for HIV two weeks ago. I don't believe she is a drug user and I didn't notice symptoms of anything. I am trying to get a copy of her test results but haven’t been successful yet.

I went to a hospital and a Doctor recommended an HIV post encounter prophylaxis consisting of emtricitabine-tenofovir and raltegravir for 28 days. I think this is designed to keep the HIV from becoming established. If I get confirmation of her test results, I would stop the treatment.

If I don't do this, what do you estimate my risk of HIV is?

What would you advise? Continue this treatment?

She says she is vaccinated for Hep B too. The medical assistant said she could still be a Hep B carrier even if vaccinated. Could that be true? I started the Hep B vaccination series. I chose not to do the HBIG prophylaxis. Wise or not?

I think I will test for other infections like gonorrhea, Syphilis and Chlamydia as soon as the incubation time has ellapsed. Any other advice?

Thank You in advance,

Mac

H. Hunter Handsfield, MD

101 months ago

Greetings, Mac. Welcome to the forum. Thanks for your question and for your confidence in our services.

In the hope of reassuring you, but at the risk of adding some confusion, I would not have prescribed post exposure prophylaxis (PEP) against HIV and I'm not sure I would have started vaccination against the hepatitis B virus (HBV). HIV first, then HBV.

Escorts, i.e. expensive female sex workers by scheduled appointment, are generally thought to have low rates of STDs in general and HIV in particular. Most are pretty wise about prevention, use condoms routinely (as yours apparently does), get checked frequently (ditto), and tend to have low risk partners -- men like you, for example. On average, probably no more than 1 in a thousand have HIV. The average transmission risk for unprotected vaginal sex, if the woman is infected, has been calculated at once for every 2,000 encounters. (Lower than you would have thought, right? Also probably lower than the PEP prescribing doctor believes.) So a quick calculation suggests your risk of having acquired HIV was around 0.001 x 0.0005 = 0.00000005. That's one chance in 2 million. Even this may be too high, if her story about recent HIV testing is true.

That said, perhaps your doctor has information about local HIV epidemiology. For example, if your escort partner is a porn film performer -- who as a group have very high rates of HIV infection -- the chance she is infected could be higher than 1 in a thousand. Or maybe there are data showing high rates in escorts in the immediate area. But without such information, I would not have prescribed PEP. In any case, if she is retested now and negative, I agree you should stop taking it.

Hepatitis B: The chance your partner is infected and infectious is extraordinarily low. I've never heard of being a carrier even if vaccinated; she would have had to be a carrier before vaccination, but in that case, she wouldn't have been vaccinated. So that possibilty really doesn't make much sense, in my opinion. I suspect the medical assistant doesn't really understand this and is making unwarranted assumptions. Getting immunized against HBV is harmless, and indeed is recommended for everyone. However, if you haven't acquired HBV by age 65, the chance you would be exposed and infected in the future is very low. It can't hurt, and now that you've started, I would recommend completing the vaccine series. At the same time, the actual risk you were exposed and infected from this one event is zero for all practial purposes.

Finally, other STDs: You can be tested now for gonorrhea and chlamydia. Your risk is very low for the reasons discussed above, but it's routine in this situation. Testing is valid any time more than 3-4 days after exposure. And a syphilis blood teat at 6 weeks also is fine -- although syphilis in this situation is almost as rare as HIV and HBV. Don't lose any sleep worrying about any of these results. Almost certainly they will be negative.

I hope this information is helpful to you. Best wishes and stay safe-- HHH, MD

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100 months ago

Dr. Handsfield,

Thanks for the reply. My kind of answer too, using numbers. (please do that more often, probably more easily said than done) BTW, did the numbers come from a study, or you considerable experience?

I forgot to mention that I tested negative for HIV about 30 hours after the encounter using the “Rapid HIV-1 and HIV-2 antibody” test. But probably irrelevant to this discussion.

The escort works independently now, but 5 or 6 months ago she worked for a couple escort services and I assume she saw many men. She sent me a photo of her test results. It’s dated March 22, 2016 and says no evidence of antibody. So, the chances are probably now less than 1 in 2,000,000, right? So, I’m assuming I can stop the PEP, do you agree? Do you know effective the PEP is? Or if there are significant dangers with it?

I’ve started the PEP and I wonder about just finishing it. Do you know what the down sides are? This seems like a game of Russian roulette but the gun has two million chambers, instead of six. And do I have the courage to spin the chamber and pull the trigger. Any downsides would help me pull the trigger.

Am I missing anything else, i.e. what else should I be tested for etc.? (You already mentioned Chlamydia, Gonorrhea & Syphilis)

In general is it better to get testing at a STD clinic (Planned Parenthood, Govt. health clinic etc.) or at my PCP’s clinic?

BTW, just curious, is this thread visible on the MedHelp.org site somewhere?

I’m an avid reader of this site and so I thought your response would be something like this. However I am very relieved to have my particular situation addressed. You and all the people that make this site happen deserve recognition from the “Paranoia Healers Association of America” or something like that. Thank You!!

Sincerely,

Mac

H. Hunter Handsfield, MD

100 months ago

The various numerical estimates come from either research or public health surveillance. Using them to calculate risk as I did is pretty much my own personal approach. I think many (most) physicians don't think it through in the same way and make knee-jerk assumptons that the risk of HIV is higher than these common sense calculations suggest.

Your 30 hour tests are useful only as a baseline, to show for sure that you were not infected before the exposure.

The risk of allergic reactions and other adverse effects of PEP drugs is very low, but it is very much higher than the chance you caught HIV. If I were in your shoes and making my own decisions, I would not have started PEP and I would stop it now. However, on this forum we never provide such direct medical advice, and I do not want you to stop PEP on the basis of my recommendations. But it would be reasonable to discuss it with your own doctor, ideally whoever prescribed it, then make a joint decision.

I do not recommend any tests other than those I mentioned above. It doesn't really matter where the testing is done; any reliable laboratory will perform the tests accurately.

To my knowledge this is the only online site where this discussion can be seen. Unless someone copies and pastes, it won't show up on MedHelp.

Thanks for the thanks about our services.

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100 months ago

Dr. Handsfield,

I will see my PCP today to discuss risks etc. Can you site a source or two for those number (the .001 and the .0005).
Thanks again for your awesome service.

Sincerely,
Mak

H. Hunter Handsfield, MD

100 months ago

0.001 is a rough guesstimate based on informal reports by experts. There are no firm data on HIV prevalence in escorts vs less upscale sex workers, but in most studies in the US, the overall rate in female sex workers is under 1%. The idea that escorts have one tenth the rate as other sex workers is probably not a bad esimate.

Re transmission risk by particular kinds of exposure, see http://www.cdc.gov./mmwr/PDF/rr/rr5402.pdf See table 1 in particular. In the last line, the calculated transmission rate of 0.5 per 10,000 exposures is 1 in 20,000. Which means my estimate above was in error by a factor of 10. One in 20K is 0.00005, and your overall risk 10 times lower than my estimate above.

From media stories, one can easily get the impression that the sexual world is immersed in HIV. In the US, it just isn't true except in selected population groups.

That completes the two follow-up comments and replies included with each new question, and so concludes this thread. Do your best to move on without worry.

Best wishes and stay safe -- HHH, MD

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