Ugh. My oldest has a cold sore and it looks like my 2 year old may have one as well. I have never had one so have no immunity. Is it ok to continue to nurse if he does or am I at risk of contracting the virus myself if I do so? Weaning has been slowly happening and he's down to nap time, bed time and first thing in the morning.
I believe I posted on this a couple of years ago. If you are seeing a cold sore now, you have already been exposed, so stopping nursing now will not prevent exposure and would be really hard on your little one(s). A cold sore can be transmitted to any place on your body, but it seems that transmission to the breast is fairly uncommon (according to what I found back when faced with what to do when my nursing 2 year old had one and I had never had one before). I'm not sure if it's because many of those children likely got the cold sores from their mothers or if it's because they are more easily transmittable on mucous membranes or some other factor(s).
FWIW, I continued to nurse my son for over 1.5 years after that with multiple outbreaks for him and have still never expressed a cold sore. I did register + for HSV in my OB blood screening panel last year, but I could easily have already been exposed from kissing my husband when he was shedding the virus but the cold sore wasn't visible. More people actually "have" HSV than express cold sores (or genital herpes), so it is entirely possible that you are already a carrier and can't catch it again.