What is chance of HSV1 transmission

[patch100]

My new partner has HSV1 confirmed by antibody test result > 40.  She is HSV2 negative (and negative for all other screened STIs).  She has never had a cold sore and never had any genital symptoms. It seems likely that she had the primary infection some time ago, and has built her own immunity.  My question is how likely that HSV1 could be passed to me, vI have read that asymptomatic shedding occurs less than 10% of the time for HSV1, but I am not sure of the transmission rate during one of these infrequent episodes. ia asymptomatic shedding, through (a) unprotected vaginal sex or (b) oral sex?   Thank you.

[auntiejessi]

Have you had a test? You should have one. About half the adult population has hsv1 and doesn't know it, since 90% will never get symptoms.

If you have it already, you don't need to worry about anything. You can't get what you already have.

Actually, oral hsv1 sheds more than that. I'm not sure where you got that 10% figure.

Shedding rates:

HSV 2 genital 15-30% of days evaluated

HSV 1 genital 3-5% of days evaluated
  
HSV 1 oral 25% of days evaluated

HSV 2 oral 1% of days evaluated

There are no studies on transmission rates for hsv1 like there are for hsv2, so I can't tell you that.

I can tell you that yes, there is a chance that you'd get it orally if you don't already have it, and yes, you could also get it genitally from oral sex.

She is only infectious from her mouth, assuming she has it orally. Since she has had no genital symptoms, statistically it's an oral infection. Vaginal sex is not an issue here.

If she has it genitally, it only sheds 3-5%, so it almost never transmits that way.

There is no way to predict that if you got it orally, that you'd ever have symptoms or not.

Most people with ghsv1 find it nothing more than an occasional nuisance. Many never get more than 1 outbreak, and never transmit it.

However, you have to decide if you are okay with these chances. I have genital herpes type 2. My experience with it says that herpes - oral or genital - is never a reason to end a good relationship or stay in a bad one. With hsv1, chances are really good that the next person you meet will also have it, as will the person after her.  

If you find yourself freaking about hsv1 - and some do - then let her find someone who won't. That's only fair to you both.

[patch100]

Thank you for the post and the sage comment at the end.  I read a paper where subjects swabbed for 30 days one year after infection and the asymptomatic shedding was c.10% of days ie 3 in 30 on average - it was higher in the period immediately following infection.  So I am thinking that perhaps the shedding diminishes over time, and that for an infection probably acquired 40 years ago, the shedding might be minimal?  (again this assumes the primary site of infection was oral, which I think is reasonably certain in this case).   One follow-up question: over time, do ones antibodies actively reduce the pathogen load, or do they merely reduce the shedding (asymptomatic and symptomatic)? Many thanks.

[patch100]

To your first question, I was tested negative 5 years and 2 partners ago, one of whom I am reasonably sure had oral HSV1 (we avoided contact during the clinical manifestations). But, yes, I could potentially stop worrying by being tested again, and ironically a positive result would ease the stress in this case.  

[auntiejessi]

In the very early stages of infection - the first 6 months, you may shed more. After that, it's pretty steady.  https://academic.oup.com/jid/article/203/2/180/908022 (This is hsv2. We can only assume hsv1 works the same way.)

Some people do find that their outbreaks reduce over time, but the virus is still shedding at the same rate.

Are you sure you had a herpes test? I ask because most STD testing doesn't include herpes testing. They will often say things like "Yep, we'll test you for everything", and not include herpes, so you should find out, or you can just do another test if you can't get those results.

Really, in the big scheme of it all, hsv1 is nothing. I'm not entirely sure what you are stressing about. At least one of your parents, probably all of your grandparents, some of your aunts, uncles, etc., all have hsv1. I know you weren't all up on them really kissing them, but chances are really excellent that you've been exposed to this a lot.