Herpes Simplex Virus in the Newborn
Last Reviewed: October 2011
What is herpes simplex virus?
Herpes simplex virus (HSV) is a virus that usually causes skin infections. There are two types of HSV: HSV type 1 usually causes small blisters on the mouth, eye or lips (cold sores) and HSV type 2 usually affects the genital area. HSV infection in newborn babies can be very severe and can even cause death. This is because newborns' immune systems are not fully developed.
Who gets HSV and how is it spread?
- About 70 percent of all adults in the U.S. are infected with HSV-1 and may shed virus in their saliva at any time during their lifetime, even if they don't have symptoms like sores in the mouth or cold sores.
- Anyone can get either type of HSV. HSV-1 infection usually occurs in childhood, before age 5, from close contact with someone shedding HSV-1, often with cold sores.
- Most HSV infections in newborns are caused by HSV-2 that the infant catches from the mother's birth canal.
- Newborns can sometimes get HSV-1 from close contact with someone who is shedding HSV-1 virus in their saliva or has an active HSV-1 outbreak (cold sores).
What are the symptoms of HSV infection?
- Most people with HSV-1 can shed it in their saliva with no symptoms, or they may have a cold sore: a small fluid filled skin blister which breaks open, crusts over, and disappears in about 21 days.
- Infected newborns may have mild symptoms at first, such as low grade fever (100.4 degrees F., or more, rectally), poor feeding, or one or more small skin blisters. This can happen two to 12 days after HSV exposure. If any of these occur, notify your doctor immediately.
- Newborns can become very sick quickly with high fever and seizures, and may become lethargic (floppy).
- HSV infection in newborns can be very severe and can even cause death.
What is the treatment for HSV?
- Cold sores in children and adults don't need to be treated. Creams with anti-HSV medicine can treat cold sore symptoms, if necessary.
- Newborns with HSV require hospitalization for intravenous antiviral medication for 21 days. Even with this treatment, some newborns can suffer death or brain damage from HSV infection.
How can you prevent your newborn from getting HSV?
- If you are pregnant and have a history or signs and symptoms of genital HSV-2 infection, tell your doctor as soon as possible. A C-section delivery is recommended if a mother has an HSV-2 outbreak near the time of birth.
- Everyone should wash their hands before touching the newborn.
- Do not kiss your baby or let others kiss your baby if you or they have cold sores on the mouth or lips.
Care instructions (recommendations for parents and caregivers):
- Wash hands thoroughly with soap and water before touching the newborn.
- Contact your doctor immediately if there are any signs of HSV infection. These include low grade fever (100.4 degrees F., or more, rectally), poor feeding, irritability, and skin rash in the form of pimples or blisters, seizures or other similar symptoms that may develop within six weeks following birth.
- All newborns should be seen by their health care provider between the first and third week of life.