Hello.  I've asked a few questions on here before and one of them included the information that a recent partner of mine had tested negative on a 4th generation hiv test at 18 days after a sexual exposure.  I discussed this with Dr. Handsfeld and he stated that my partner was beyond a point where she could have possibly transmitted anything due to the timing of the negative test.  My question is this: would the same apply if the partner had tested negative at 14 days after a sexual exposure, essentially meaning that it would have not been possible for them to transmit hiv?  I tried looking through the directory of answered questions but couldn't quite find an answer.  I appreciate your help.  Thank you. 

My apology, I forgot to add this was after a male/female unprotected oral encounter.  Also I ask because we discussed STDs and I showed her my latest negative result and said I don't mind getting another if it made her feel better.  I talked to her about my questions on here and didn't mind buying a new question to get clarification because I support your site.  Thanks again.  

Welcome back to the Forum.  On this occasion I'll be answering your questions.  In preparing to do so, I reviewed your earlier interactions with Dr. Handsfield and agree with all that he said.  Your encounter was virtually no risk for HIV to start with and your partner's subsequent negative test 14 days following your encounter provides proof that there was no way that she could have transmitted the virus to you during your casual encounter.  Had she had HIV at the time of the encounter, her 14 day test would have been positive.  It was not- you were not exposed.---

Thank you doctor, I appreciate your straightforward and prompt response.  Just to be clear, my partner testing negative on a 4th generation test 14 days after an encounter is 100% proof that they could not have transmitted hiv during that encounter?  Thanks.

Also just to clarify, I had discussed with dr. Handsfeld my partner testing negative for hiv 18 days after an encounter.  This is a new encounter and I was asking if 14 days was just as conclusive as 18 days if my partner were to test negative on a 4th generation test.  Thank you so much.

Sigh.  This is entirely repetitive.  I understood you the first time and that your partner tested at 14 days, not 18 days following your entirely no risk encounter.  No change in my assessment.---

Thank you doctor, and my apology for the confusion on my end.  You’ve answered my main question but as I have one left I was hoping to get some clarification on oral sex risks for hiv infection.  From everything I’ve seen from reputable sources, receiving fellatio (that is your partner’s mouth on your genitals) is either “physiologically improbable” to “NO” risk for hiv.  The San Francisco city clinic website specially says that hiv cannot be transmitted from oral to penis and that hiv cannot be transmitted from performing cunnilingus on the vulva.  Would you agree with this assessment?  I only ask because there is a litany of different information from different sources out there that range from oral sex being an “1%” chance to “1 in 10,000 chance” to “no chance” and I’m trying to assess risk for future encounters that may occur.  

Almost forgot one thing I meant to include: if your partner tests negative on a 4th generation hiv test the day after a sexual encounter with them, does that rule out the possibility they had transmissible hiv during the encounter?  Thank you very much, it is truly helpful.

Final Responses---