What is impetigo?

Q: My baby has crusty blisters around his nose and mouth. What's happening?

A: The sores you see on your baby's face may be impetigo, a contagious infection caused by staph or strep bacteria. Although impetigo is most common on the face and bottom, it can occur anywhere the skin has been broken and bacteria have invaded. Impetigo usually starts with red sores that quickly rupture, ooze and form a yellowish-brown crust. Anyone can contract impetigo, but children between 2 and 6 are most vulnerable because their immune systems are still developing and they're often in groups settings (like daycare) where staph and strep are more common. Your child probably contracted impetigo when bacteria entered his skin through a rash or bug bite, but it can also affect otherwise healthy-looking skin. Impetigo must be diagnosed by your pediatrician and is usually treated with antibiotics, although mild cases may go away on their own. Let your doctor make the call.

While your baby is healing, soften and clean the sores with warm water and apply an antibiotic ointment several times a day. Impetigo is highly contagious, so discourage your child from touching his face since this can spread the infection can spread to other parts of the body. Covering the area with gauze is a great way to prevent scratching. You should wear gloves while caring for your child so you don't become infected, and be sure to wash all your child's clothes, towels, and sheets in hot water to prevent re-infection. After your child begins antibiotics, the infection should clear up in a few days (usually he'll no longer be contagious after 24 hours of treatment). Even though your child is feeling and looking better, you should still finish the whole course of antibiotics so the bacteria don't return.

If the outbreak does not begin clearing up quickly after your baby starts antibiotics, see your pediatrician again. A cluster of tiny blisters that scab in a couple of days may be a herpes infection (one on the mouth is called a cold sore) and not impetigo.

Copyright 2003 Meredith Corporation. Updated 2009.