Herpes infection in babies is called neonatal herpes. This type of infection occurs in newborns and is caused by the herpes simplex virus (also known as human herpes virus). Although both herpes simplex virus type 1 (HSV1, also known as HHV1) and herpes simplex virus type 2 (HSV2, also known as HHV2) can both cause neonatal herpes, most cases are caused by HSV2. Transmission usually occurs when a parent with oral or genital herpes passes on the virus to the baby before, during, or soon after the baby is born. Usually, the virus is passed on during delivery. The disease can affect the skin, eyes, mouth, lungs, liver, or central nervous system (brain and spinal cord).

There are a few challenges to the treatment of neonatal herpes. The first is that treatment cannot undo damage already done to the body, although it can probably stop the damage from getting worse. Second, treatment does not cure herpes - it only helps treat the symptoms. The virus can hide within the body (become latent), only to reappear later in life.

Neonatal herpes needs to be detected and treated quickly. If a newborn baby becomes ill and the mother has a history of herpes, she should make sure that the pediatrician knows of her history. If the father or any other sexual partner of the mother has herpes, that fact is also important, since the mother could then have herpes without knowing it. Remember, too, that neonatal herpes can occur even where both parents have never knowingly had a herpes sore of any kind. Make sure the pediatrician or another health care professional explains to you how the possibilities of herpes and other problems are being investigated. It is certainly possible to have good medical reasons not to consider the diagnosis of herpes in a newborn, but you should suggest looking for herpes just to make sure that your doctor has thought of the possibility. If your doctor does not consider herpes a possibility, he or she should explain why not.

Medication therapy

The antiviral medication acyclovir (Zovirax®) is used in treating neonatal herpes. It is usually given by injection. It cannot cure herpes or reverse damage that has already occurred, but it can reduce symptoms and decrease the risk of further damage.

Doctors can now diagnose neonatal herpes more quickly and at much milder stages than in years past. This means a greater likelihood of better results for newborns with herpes. Still, the diagnosis is all too often made after some irreversible harm has already come to the newborn baby.

Treatment with acyclovir should be started if:

  • an infection is suspected (e.g., if lesions are present on the newborn's skin)
  • if laboratory tests indicate an infection
  • if at the time of delivery, the newborn's mother has a primary (first-time) genital herpes infection

Although treatment is available for herpes, there is no cure. Prevention of neonatal herpes is challenging. Preventing infection in the parents can help reduce the newborn's risk of infection. Although there may be a vaccine on the way, more research is still needed.

Any medication use, especially in babies or young children, needs to be undertaken only with the careful advice, prescription, and follow-up of a physician. This and other medical issues need to be discussed with your baby's physician. In the future, we may be able to further protect the infant with vaccines for the mother, the infant, or both, and treat them with more potent medications.

Stephen L. Sacks, MD, FRCPC, with revisions by the MediResource clinical team