[Question #2069] Question - Risks & Tests

91 months ago

Hello doctors,

Situation:

Got unprotected fellatio from a sex worker (masseuse) in Spain; she was aged approximately 30 and was working in an establishment with other workers. This act lasted approximately 3 minutes, and I believe all additional contact can be deemed safe. This happened at 5am on a Saturday morning. On Monday afternoon (1pm) I conducted a general urine test for STIs, which has now been sent to the lab. I have no symptoms, and it is now Tuesday.

Questions:

1. What are the true risks associated with unprotected oral (mouth to penis), considering she was a sex worker?
2. Should I consider test results void considering the timeframe between exposure and testing (2.5 days), or can I see as encouraging if negative?
3. Would you recommend I get re-tested in 2 - 3 weeks if these results return as negative?

There is a lot of conflicting information out there, and nearly all websites promote huge caution when engaging in oral sex.

Edward W. Hook M.D.

91 months ago

Welcome to our Forum. I'll try to help. Commercial sex workers tend to be cautions about STIs (bad for business), particularly when they work in a fixed location. In addition, different sex acts have difference STI risks. Thus taking all into consideration this was a low risk encounter and the testing you did will effectively rule out the most common STIs. Here are some facts:

1. HIV is uncommon in Spain with a national prevalence of less than 1/2 of 1% in adults (admittedly, probably higher in adults). further, I am not aware of any instance or report in which a person has been proven to acquire HIV from receipt of oral sex. I would have no concerns about HIV.

2. Oral sex only relatively rarely leads to infection with other STIs. The absence of symptoms at this time if further evidence that you were not infected. When it does, the most common problems are either gonorrhea of non-gonococcal urethritis NGU) caused by mouth organisms introduced in to the urethra during sex. This sort of non-chlamydial NGU (chlamydia infections are very rare in the throat) is not clearly and STI in the traditional sense, is not readily transmitted to sex partners like other STIs, and in not associated with complications. In the United Kingdom, many specialists do not treat NGU associated with oral sex. When treated, oral sex-related NGU typically resolves quickly. When your tests are negative as I am confident they will be, you can be confident in the result.

3. Lesion diseases like herpes and syphilis are spread by direct contact with a sore which you most likely would have seen and are very, very rare following oral sex. Your risk is tiny. If you do not develop sores or lesions at a site of contact within 2 (for herpes) or 3 (for syphilis) weeks of contact, you can be confident that you did not acquire one of them. Personally I do not feel any specific testing is needed in your case for the exposure you describe. If you need syphilis testing the "official" time when results will be definitive is in 6-8 weeks although I would be confident in the result in your case at 4 weeks. We recommend against blood tests for herpes- they are too often misleading due to false positive results.

I hope these comments are helpful. EWH

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91 months ago

Thank you Dr. Hook,

I wanted to emphasise in particular the issue of testing 2.5 days after exposure. With specific reference to Chlamydia and Gonorrhea, which is measured through the urine sample I provided after that period. If I receive negative results in a few days, can this issue be completely shelved, or would you recommend a later test to be certain (according to official incubation period guidelines)?

The above situation would be in the absence of symptoms; if symptoms arise in the next 2 weeks, I will certainly re-test.

Three final short questions to wrap it up;

1. Upon contracting an NGU is it passable to another partner when engaging with unprotected vaginal sex?
2. Are NGUs typically tested via urine samples at the same time as G & C?
3. Is there a reason why your advice (as a group of professionals) is so different to other sources, and even credible experts on the web?

Again, thank you for your help.

Edward W. Hook M.D.

91 months ago

I considered the time-frame you mentioned in my response. Your test results should be believed nd if you develop symptoms after a negative test, you should look for another explanation.

1. As stated above, there is no clear evidence that non-chlamydial NGU is transmissible or has negative consequences for sex partners. Chlamydia, of course, is transmissible. Other pathogens listed as causing NGU (trichamonas, Mycoplasma genitalium) are not known to be transmitted through oral sex.

2. No, the diagnosis of NGU is made with a urethral swab, taken from the inside of the penis. In your situation, there is no reason for this as the major pathogen you are looking for is gonorrhea and (very rarely) chlamydia.

3. I'm not sure who or what internet sites you are referring too. The information available on the web is all too often incorrect or taken out of context.

EWH

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91 months ago

Thank you Dr. Hook, this will be my last reply. Many thanks for your time.

Regarding the advice of others on the web. With specific reference to the time period between exposure and testing, why does almost every other expert recommend a minimum of 2 - 3 weeks for G & C?

I know you can only speak categorically from your own research, but I'm surprised that there is such a disparity between guidance.

Edward W. Hook M.D.

91 months ago

I can't clarify why anyone who understands the biology of gonorrhea or chlamydia would tell you that you need to wait 2-3 weeks before testing. This has no basis in science and is simply wrong. Just consider, typically persons with gonorrhea develop symptoms within 3-5 days of exposure. At that time cultures and stains for the organism are positive. Whomever you are suggesting are "other experts" is wrong.

As you mention, this will end this thread. Take care. eWH

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