Hello Doctors.  This occurred with a Stripper who I highly suspect was a drug user.  I received a hand job with her saliva, followed by 45 seconds of unprotected oral and some frottage that occurred over her panties as she noted she had her period.  Had Chlamydia and Gonorrhoeae test after 8 days that came back negative. My urine lab came back clear. I tested yesterday at 35 days for HIV with a 4th Gen test and Syphilis RPR.  I know its a bit early at 5 weeks instead of 6.

1. What should I be on the look-out for with regard to a chancre? What does it look like as it forms? 

2. If this is the new formation of a chancre and I am positive for Syphilis, does that increase my risk of HIV from this event?

Welcome to the forum. Thank you for your confidence in our services.

You really needn’t be at all worried about HIV – you didn’t actually need testing. HIV has never been documented to be transmitted by oral sex oral to penis (with only a few known infections in the other direction, i.e. penile to oral). The virus also is rarely if ever transmitted by saliva and is not transmitted by hand-genital contact.

As for syphilis, it continues to be quite rare in female sex workers in the US (most infection are in man who have sex with men); and oral sex is not a common transmission route and also not a risk from hand-genital contact, even if genital fluids are used for lubrication.

Your tests for both HIV and syphilis are nearly conclusive. Although 6 weeks is ideal, by 7 weeks (35 days) virtually all newly infected persons have positive test results.

To your specific questions:

1. If a chancre is going to appear at all, it does so no later than 2-3 weeks after exposure. With nothing yet, that alone (even without a blood test) is strong evidence you weren’t infected. Chancres typically start with a reddened skin bump that becomes an open sore within a few days. You can google “chancre photo” or similar term to find lots of images online.

2. In theory, if a sex partner has both syphilis and HIV, the chance of acquiring HIV probably is somewhat higher if syphilis is transmitted. However, the odds of this scenario in your situation are exceedingly low. As discussed above, the risk was low to start, and your negative blood tests show that almost certainly you were not infected with either one.

Had you asked ahead of time, I would have advised that the risk of both syphilis and HIV was low enough that you didn’t need testing. But having started down that path, I’m sure you’ll remain nervous until have had conclusively negative results. So for final reassurance have a repeat syphilis blood test and HIV AgAb (4^thgeneration) blood test when you reach 6 weeks after the event. The results will be negative.

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