Thanks once again for this forum - I have read many of the questions and they have certainly allowed me to have a much better understanding of STI transmission.  I have read that heterosexual syphilis is not that common and oral heterosexual sex even less - The incident involved heterosexual sex - 1st time was 08/17/23 - mutual unprotected oral both way - both caucasian - she 35 me 63 - met on sugar daddy website - both educated - both fully employed - both discussed safe sex and sexual history - both agreed - to have unprotected mutual oral sex only and always use condom for insertive sex - she was concerned about pregnancy as well -  second no later than 09/13/23 - mutual unprotected oral both way - condom protected vaginal sex - condom remained in tact - no failure. I have read on this forum and the cdc website that the first sign of syphilis is a chancre sore. It usually occurs approximately three weeks after infection. The cdc website also gives a range between 10 days to 90 days.

Welcome back to the Forum.  I think your analyses have answered your questions.  The encounter you described was low risk and the timing and lesions you describe are in no way suggestive of syphilis.  As you point out, the CDC guidelines for the development of syphilis are quite conservative, The majority of syphilis chancres appear within 3 weeks (21 days) of exposure and the idea that a chancre would appear more than 4 months after an exposure is simply not a possibility. Further, the lesions you describe in no way suggest syphilis.  OTOH, the fact that these lesions bleed when they merely come into contact with your underwear (I presume you were not repeatedly examining the lesions) is highly unusual and warrants a trip to your dermatologist- not because I suspect an STI but because for lesions to bleed with light contact is quite unusual---

Dr. Hook - your comment put my mind at ease - I thank you 

The observed data are that cunnilingus on an infected person very rarely leads to infection with HIV.  There are likely many reasons for this.  Clearly virus is present in vaginal secretions from multiple sources including the cervix, the vagina itself as well as from Bartholin's glands.  The oral cavity seems more resistant to infection than genital sites.  Insertion of the tongue into the vagina is less abrasive than penile-vaginal sex.  All of these likely contribute to the low risk of acquisition of HIV from cunnilingus.  EWH---

Let me thank you in advance for answering my questions 

As you know, these will be the final responses as part of this thread.---