Question:
My 15 yr old daughter and her boyfriend only had sex and oral sex with each other and no one else. They were both virgins. We know our daughter and her boyfriend, and are convinced this is true. She only "kissed" one boy before her boyfriend when she was 14, no sex involved at all. Her boyfriend never even kissed a girl.
We noticed she has had a fair amount of sores in her mouth since she got braces at age 13. Possibly earlier and we never noticed.
My daughter has just been diagnosed with genital herpes. Not yet sure if herpes 1 or 2. Looking for explanation how this could happen.

Answer:
If your daughter is a virgin, this is probably a case of HSV-1 (typically cold sores) that has been transferred to the genital area via oral sex. Either she had HSV-1 first and gave it to her boyfriend via kissing, or he had it first, or they both already had it as children! An estimated 80 percent of the population has this first kind of herpes strain, and it's commonly passed from skin-to-skin contact, so even a parent kissing their child can pass it on.

She may have had the HSV-1 virus (cold sores) for years but they might've only cropped up when she got braces because the irritation triggered an outbreak.

If this is HSV-1, she may only get mild outbreaks, and some scientists suggest that it's less contagious than HSV-2 as well.

(based on original question by user vinniemac)