[Question #8417] Herpes and syphillis testing

45 months ago

Hey docs,

Me again. 12 weeks is approaching from my encounter with a csw where I received a protected blow job. I tested negative for herpes(1/2) igg and syphillis RPR at 6 weeks. I’ve read that 12 weeks is the best time to test for herpes post exposure. I’m not sure about syphillis.

I’ve had no symptoms of either herpes or syphillis although I have been looking thoroughly since my possible exposure. As you can tell I have some anxiety about this. As I don’t want to give anything to my partner.

1) Is my negative syphillis test (RPR) conclusive at 6 weeks?

2) Can I trust my negative herpes 1 and 2 test (igg) at 6 weeks?

3) Do you think I should test for herpes at the 12 week mark?

H. Hunter Handsfield, MD

45 months ago

Welcome back. I understand your anxieties, but I'm still sorry you found it necessary to return. I reviewed your two recent discussions with me and Terri and wouldn't change anything either of us said in those threads. This event was too low risk for you to be tested for herpes, syphilis, or anything else, in the absence of symptoms. And I agree with Terri's advice that there was no need for any further testing beyond the results you discussed with her. To your questions:

1. The outside limit for conclusive of RPR testing has never been formally studied or analyzed. Six weeks probably is sufficient, and is what I usually recommend, but some experts say 8 or 12 weeks. However, in the US it is the rare female CSW who has syphilis, and absence of an obvious sore (chancre) on your penis also is strong evidence you were not infected.

2. You can never "trust" a negative HSV1 blood test, since 30% of infected people never develop a positive result. However, the negative result at 6 weeks plus absence of symptoms is strong evidence you were not infected.

3. You were not at risk for HSV2, since that virus rarely infects the oral cavity and therefore oral sex transmits HSV2 extremely rarely, if ever. However, if you feel you need conclusive laboratory evidence you weren't infected, you'll need to test again at 12 weeks. Or, even better, 16 weeks.

Putting the situation in personal terms, if somehow I were in your situation, I would not have any further tests (but then I wouldn't have been tested at all); and I would be continuing unprotected sex with my wife, without worry of infecting her with any STI.

I hope this information is helpful. Let me know if anything isn't clear.

HHH, MD

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44 months ago

Thanks for your quick response. A couple of things.

What are the chances that I received hepatitis c from this encounter? Would you test for it? I was tested for all the hepatitis variants a,b,c at 6 weeks. They all came back negative.

The way I understand from my research it typically takes 8 weeks for hep c to show up on a blood test.

Thanks

H. Hunter Handsfield, MD

44 months ago

Zero risk for hepatitis C virus. HCV has been oversold as an STI: the only proved sexual transmission occurs between men having sex with men via potentially traumatic anal sex practices. The frequency of HCV in the heterosexual spouses of infected persons, even after 20 years or more, is no higher than in the rest of the population. And one calculation (from Denmark, as I recall) is that the risk from unprotected vaginal sex with an infected partner is one chance in 190,000. In other words, zero. And for sure no risk from oral sex. Testing for any hepatitis virus after such an exposure was a waste of money. Don't waste any more on this!---

44 months ago

At this point if I were too receive a negative test for herpes 1 after a negative at 6 weeks. As well as no symptoms would you be confident that I was not infected with hsv 1?

44 months ago

Just to be clear. I DID go ahead and get tested for hsv 1/2 at 12 weeks. So if I receive a negative result again for herpes 1 as well as no symptoms would you be confident that I was not infected?

Thanks so much for your help. This will be the last you hear from me I swear

H. Hunter Handsfield, MD

44 months ago

The HSV tests confirm you do not have HSV2 and probably not HSV1. But you can never be sure about HSV1; see no. 2 in my answer above.

That concludes this thread. Repeated questions on the same topic are not permitted, so this will have to be your last on these issues. Thanks for your understanding. I hope the discussions have been helpful. Best wishes and stay safe.

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44 months ago

I lied, one more question. How likely is Trich transmission from a protected bj? Thanks Rhys my last one

H. Hunter Handsfield, MD

44 months ago

Trich never infects the oral cavity, therefore never a risk by oral sex (whether or not condom protected).---