Welcome to the forum. Thanks for your question and your confidence in our services.
3) Going first to question 3, cunnilingus indeed is a very safe sexual activity, with low risk for all STDs and zero risk for some. As for "brass tacks", your symptoms are much more consistent with a garden variety, non-STD upper respiratory infection than for any STD. The problem conceivably could nonetheless be related to the sexual exposure described: being close enough for sex of any kind obviously carries potential for transmission of colds and related viruses; and some viruses (e.g. adenovirus) can involve both the genital and upper respiratory tracts. However, your symptoms came up quite late for them to be related to that event. Almost all such viral infections would show up within 3-5 days, not almost 2 weeks later.
1) While some STDs are theoretically possible from the event described, but oral gonorrhea and chlamydia rarely cause symptoms at all; and if symptomatic, would also usually show up within a few days. Also, the antibiotics you had would have promptly cured either of these. (They also would have aborted syphilis, but that's even more unlikely based on both the exposure and your symptoms.)
As for HIV, your symptoms could go along with it, but HIV has never been proved (or to my knowledge even suspected) to have been acquired through cunnilingus, and unless your new partner is at special risk for HIV (injection drug use, immigrant from an HIV endemic part of the world, etc), it is exceedingly unlikely she has HIV. On average, well under 1 in 1,000 sexually active women in the US have HIV. Also these symptoms, without fever and/or generalized skin rash, don't fit well with acute HIV. I agree mono also could fit, and would recommend testing for it -- even though I agree that repeat infections are rare. Finally, HIV doesn't cause only a few tender nodes in one area of the body; typically they are painless and all over the body, e.g. armpits, groin, etc in addition to the neck area.
2) Herpes? Of all STDs, this probably is the most likely -- but here too the time duration is against it. Initial symptoms can be delayed as long as 2 weeks, but that's uncommon; and herpes rarely if ever causes sore throat or lymph node inflammation without also causing multiple painful open sores in the mouth and/or throat -- not the sort of symptom you would miss. That said, I think you should be tested for it. If indeed it's herpes, either HSV1 or HSV2 could be responsible, acquired by kissing or by cunnilingus, respectively. (But if you've had oral herpes yourself, you're immune to a new HSV1 infection.)
So all things considered, I am very confident this isn't HIV/ARS. As just noted, I'm less certain about herpes -- I think it is a fairly distant possibility, but not impossible. Probably this is unrelated to the sexual exposures described. However, if your partner also has been experiencing a similar illness, that would support a shared non-STD viral infection. Have you spoken with her about all this? Including any past history of either oral or genital herpes?
What to do now? I would go ahead with the mono test, and would also suggest HIV testing -- not because I think it likely at all, but because it's on your mind and I doubt you'll rest easy until it has been ruled out. You're at a point now when a standard antigen-antibody test ("4th generation" test) would detect 90-95% of new infections. Also a repeat evaluation by your doctor, to include careful inspection of your mouth and throat for ulcers you might not have noticed, and (with or without ulcers) a throat swab to test for an HSV DNA test. You might consider printing out this thread as a framework for discussion with your doctor.
I'll be interested to hear all this shakes out. In the meantime, I hope this information has been helpful. Let me know if anything isn't clear.
HHH, MD
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