What are the odds?

[Skiff]

Sir,

I've had cold sores for over 20 years.  I usually have an outbreak once or twice a year and have never passed this on to one of my partners that I am aware of.  I had an outbreak a little over two weeks ago and I took my Acyclovir as prescribed ( I've been using it and always have a bottle at the ready).  By the time the bottle was finished, the sore had run its course and healed completely (or so I thought).  I've been seeing the same lady for over 2 years and we've had a good, active sex life all throughout our relationship.  I've always refrianed from kissing her anywhere during the first signs of an outbreak until the sore has run its course.  Last night I performed oral sex on her and then early this morning I notice the tell tale signs.  It's been 24 hours and the blisters have formed in the usual area on my lip.  I've never had back-to-back outbreaks though I have been very stressed at work.  I'm sick with worry that she is going to contract genital herpes!  Please give me your honest opinion on the odds that she will contract the disease. I guess we've been lucky thus far.  I've never had a situation like this and I will never perform oral sex on her again...period!
Thank you for your consideration.

Steve

[Edward W Hook, MD]

Welcome to the Forum.  I have several pieces of advice for you regarding your concerns.  Let's start with your risk of transmission.  The fact that you had an outbreak start soon after performing oral sex on your partner does not by any means guarantee that she is going to get infection.  Most exposures to infected partners do not lead to transmission and that you developed a typical outbreak 24 hours after your last contact does not mean that you were shedding the virus at the time of oral sex.  Chances are that you did not transmit your infection to her.  

In addition, unless she has been tested, there is a more than 50/50 chance that she already has HSV-1 but does not know it.  Remember. about 60% of Americans have HSV-1 but only 90% of those who are infected know that they are.  If she already has HSV-1, she cannot get it again from you.

If she does not develop lesions in the next 10-12 days, she di d not get infected from the encounter you describe.

Finally, I presume that she knows of your cold sores.  Thus you should express your concerns to her.  In addition, I would recommend that she have a type-specific HSV blood test such as the HerpeSelect.  As pointed out above, she may already be infected and it would be good to know.  

Hope this is helpful. Take care.  EWH

[Edward W Hook, MD]

Actually, if you do not develop lesions, I would not do any further testing.  If you are looking for lesions and have acquired HSV you will almost certainly be aware of it.  On the other hand, with the blood test, if you have no lesions or other good reason to be concerned, the blood test is more likely to be false positive than to make a true diagnosis.  EWH

[Skiff]

Dr. Hook,

So, concerning this episode, we could wait to see if she develops lesions in the next 10 - 12 days (something will happen by that time, right?)  If not, then schedule the tests (HSV-1 and HSV-2) as it will provide useful information going forward?

thanks

[Edward W Hook, MD]

You've been going out for two years.  I think you could get the HerpeSelect tests at this time.  While it will not help with this particular episode, it will provide useful information for the two of you going forward.  EWH

[Skiff]

Dr. Hook,
How long should she/we wait before having the HerpeSelect blodd test?

Thanks again for all your help!