Preventing cold sores in babies
© 2013 Roy Benaroch, MD
Eileen wrote in: “I’ve been cursed with cold sores since I was little, and I’m having yet another outbreak. However, I now have a baby to worry about, and I desperately want to avoid passing this on to my little girl. Do those over-the-counter cold sore remedies do anything? Would going to my doctor for a prescription help?”
Cold sores are those annoying sores near the mouth, most often right on the border of the lip and face. They’re caused by herpes simplex virus, and like other herpes family infections this virus becomes dormant in the body after the first infection. In some people, herpes simplex likes to pop back out every once in a while, causing recurrent sores. We don’t know why some people get frequent recurrences, while most other people never get any recurrences.
What we do know is that almost all of us, by the time we’re adults, are infected with the kind of herpes simplex that usually causes these oral sores. And many of us shed the virus intermittently—meaning we’re contagious and spreading the virus around—even when we don’t have any symptoms or sores at all. So it’s nearly impossible to avoid exposure to this virus.
Recurring outbreaks are somewhat less contagious than the first outbreak, at least in people with normal immune systems. Treatment options include topical medicines, either OTC or prescription—these are highly effective in making the sores look shiny, but pretty much ineffective at making them go away or making them less contagious. Oral anti-viral medicines (these are all prescriptions) can make the outbreak shorter and can decrease viral shedding and contagiousness, especially if they’re begun right at the start of the outbreak (or even better, before the sore even appears. Some people can tell they’re going to get a sore even before they can see it.) For people who have frequent outbreaks, taking anti-viral medications every single day can help suppress the next outbreak, too.
But again: people with herpes simplex can shed virus even when they have no symptoms or sores at all! So, again, it’s very difficult to prevent the spread of this virus.
If mom has had recurrent herpes simplex sores for years, her baby will probably be born with high concentrations of anti-herpes antibodies that will protect the baby from infection for the first six months of life. After that, those antibodies fade away, opening the window for infection. A worse scenario for baby is when mom has her first outbreak of herpes (oral herpes or genital herpes) right near the end of pregnancy—that means mom has no antibodies to share across the placenta with baby, and that baby can get a widespread, potentially catastrophic herpes infection during or right after birth.
For Eileen: especially as you get closer to your baby’s six month birthday, it would be a good idea for you to talk with your doctor about the pros and cons of an anti-viral medicine, either to take continuously or to take as a burst dose at the first sign of an outbreak. Most of these medicines are safe with nursing. There’s no guarantee that they’ll prevent transmission, but they may help delay or prevent your baby from picking up the virus.