This is highly suggestive of initial oral herpes. HSV1 is the most likely cause, but HSV2 also is possible in this situation. Onset usually is 3-5 days after exposure, but it can take up to a couple of weeks. In addition, none of the specific sexual events described is likely to transmit HSV of either type, and onset at only 2 days is atypical. For those reasons, I am suspicious that you acquired it during one of the other sexual exposures you had in the last month -- especially if one of those occurred roughly 5-15 days before onset. Did either of those other events include kissing or cunnilingus? (I'm assuming your CSW partners are female -- but these comments also are valid if they were male.

In addition, oral herpes can be from a regular sex partner who has HSV1. Does your partner have oral herpes (cold sores)?

Other viral infections also could be responsible -- conditions called herpangina and hand foot and mouth disease, caused by non sexually transmitted viruses in the viral groups called coxsackievirus and echovirus. These would usually imply contact with infected child; infections in adults are uncommon but could occur. These are considerations if you have young kids at home or are otherwise in touch with children.

I imagine you're also worried about HIV. While that conceivably could be the problem, it is very unlikely. Acute HIV infection sometimes includes oral ulcers, but nearly so many or so severe as your comments suggest.

What to do now? Immediately seek medical care. You can start with your GP -- although if s/he is not highly experienced in STIs or infectious diseases, you might ask for immediate referral to such an expert. The UK's NHS genitourinary medicine (GUM) clinics are superb and likely would see you immediately. Or an infectious diseases specialist. One way or another, you need to be tested for oral HSV by PCR; a blood test for HSV 1 and 2 (too soon to be positive, but as a baseline against which to compare follow-up testing later on). Finally, if the professional you see agrees initial herpes is possible, you should immediately be started on treatment with valacyclovir or acyclovir -- without waiting for your test results.

Another aspect concerns the health of your most recent CSW partner. If you have herpes, you likely were highly infectious in the 2-3 days before onset of symptoms -- in other words, you could have exposed her and she should be on the alert about it. You also should contact your two other recent CSW contacts about symptoms they may have and whether they have known genital or oral histories.

I have asked Terri Warren, our forum's herpes expert, to take a look this discussion and to weigh in if she has additional thoughts about it. In the meantime, I hope these comments are helpful. Let me know if anything isn't clear. Best wishes and good luck.

HHH, MD

In answer to your questions, my previous exposures were on the 11th July and the 1st of August (so at least a month ago, apologies I miscalculated originally) and there was no kissing or cunnilingus on either occasion, just brief protected oral.  Is it plausible that I would have contracted HSV in my mouth under these circumstances? I  thought canker sores and mouth ulcers were separate from cold sores / herpetic lesions? For what it is worth I have had outbreaks of canker sores in the past, and they usually coincide with flu / cold symptoms - but this dates back to my childhood.

I am in a regular partnership, but she is displaying no cold sores, although she is also experiencing flu symptoms now. We do also have a child, 6 years old - would this make Herpangina or Hand Foot & Mouth more likely do you think? Is it the suggestive timing that makes you rule out just the flu?

Apologies if it seems like I am questioning your judgment, I will certainly follow the steps you have laid out, I am just praying that this isn't herpes.

This information exonerates your CSW partner as a source, even if it's herpes. Onset of your symptoms less than 48 hours later is too soon, and none of the events you describe seem to have exposed your mouth. The other two sexual visits with her were too long ago. That your regular partner has had no cold sores doesn't exclude HSV1, since most infections cause no symptoms. So you have to consider the likelihood that she or your child was the source, and your partner's flu-like symptoms might indeed be significant.

This information does indeed make herpangina or hand-foot-and mouth disease more likely. You need to discuss the situation with your partner. Even if this turns out to be HSV1 or even HSV2, given the monogamous nature of your relationship (from your partner's perspective), herpes of either type would not imply either of you has had other sex partners, and you need not mention your CSW experiences to your partner. 

You're right that canker sores and herpes are entirely different. And whichever virus is causing your illness, it is your first exposure to it, not recurrence of a past infection.

You definitely need to get into care ASAP. Testing by PCR or other methods, both for HSV and perhaps for echo- or coxscackievirus, is most accurate the earlier it is done; and if your doctor considers herpes a possibility, treatment with valacyclovir or acyclovir is more effective the sooner it is started. (There is no antiviral treatment for herpangina or HF&M disease.) I also strongly suggest you discuss the situation with your partner. As noted above, even if it turns out you have initial HSV1 or 2, it will not imply sexual infidelity on either your part or hers. Depending on whether your child has had symptoms, it might also be good to involve his pediatrician; or your family GP, if that's your health care situation.