Just as the symptoms of genital herpes vary with the location of the infection, so do the signs of neonatal herpes.

In some unusual cases, herpes is already present at birth. Since infection usually begins at the time of birth, however, it typically takes several days to a couple of weeks to become evident.

The most common herpes infection in newborns is on the skin. The skin sore looks much like a sore on an adult - a single vesicle (blister) or cluster of vesicles.

Occasionally, herpes begins as a red or purplish rash.

Because many very mild skin rashes of infancy mimic herpes, it is important to ask a doctor's opinion when a skin rash develops in a newborn. Genuine herpes sores may be found anywhere on the skin, especially on the head of a baby born head first, the buttocks of a baby born rear first, and so on.

Figure 1 shows a newborn who was delivered feet first. However, skin lesions in a newborn are not always or only found at the site of first contact with the virus. Figure 2 shows the recurrent herpes on the hand of a baby that had neonatal herpes at birth.

neonatal herpes on foot

Figure 1

Neonatal herpes on foot

neonatal herpes on hand

Figure 2

Neonatal herpes on hand

Another common site of herpes of the newborn is the eyes. Most babies receive either silver nitrate or an antibiotic ointment in their eyes at birth to prevent eye infections caused by certain types of sexually transmitted infections, such as chlamydia and gonnorhea. However, this does not provide protection from herpes in the eyes. Herpes infection of the eye is often detectable only by an examination by an ophthalmologist (eye specialist). Talk to your doctor or your baby's doctor if you have concerns about a herpes infection in your baby's eyes.

How severe can herpes infection of a newborn become?

Most studies suggest that many newborns who develop genital herpes never develop skin lesions at all. The more severe neonatal herpes syndrome is infection of the central nervous system (the brain). This infection spreads by being carried in the blood and distributed in many parts of the body. Brain infection tends to appear at 1 to 4 weeks of age.

An affected baby may suddenly lose his or her active behaviour and become lethargic. The baby may stop caring about things such as feeding, or may do just the opposite and become very irritable. This, of course, is a very common thing in normal babies as well, but an irritable baby should be assessed to make sure it is nothing more than "just colic." Shaking, twitching, or fits - like epileptic fits - should be checked out by a physician without delay. Babies with herpes infection of the nervous system may have skin sores, but very often a baby with serious herpes infection shows no skin problem whatsoever.

The same is true for disseminated herpes (herpes infection found in many parts of the body) - skin sores may or may not be present. Disseminated herpes appears a bit earlier, often within the first 7 days of life. In most cases, herpes is present at birth, implying that herpes infected the baby inside the womb. There is no known specific method for prevention of womb infection.

Most babies with disseminated herpes have nonspecific symptoms, including apparent sluggishness, going off feeding, and vomiting. An affected baby may become gravely ill very rapidly. Jaundice (yellow skin) is very common in infants. Jaundice may be the result of herpes or it may be caused by many other things. Sometimes a baby with herpes gets pneumonia, has difficulty breathing, or has apnea - spells with no breathing at all. These are serious problems that require intensive investigation in hospital. If the mother has herpes, the pediatrician needs to know in order to consider this possibility.

All of the scenarios discussed above, with the possible exception of skin sores, have nonspecific symptoms. This is the problem. So many things - some infectious, some noninfectious; some very serious, some very minor - show themselves in exactly the same way. Even if your baby gets all of these symptoms, herpes is unlikely. Neonatal herpes is exceedingly unlikely to occur and is highly preventable. Furthermore, if it happens in spite of efforts at prevention, it is treatable. In fact, the problem with treatment is less the difficulty of finding a useful medication and more the delay that often occurs before the diagnosis is made. If the first sign of something serious is nonspecific, it may take days to find the correct diagnosis. The delay makes treatment more difficult. If your infant becomes ill, get medical attention. Herpes can be diagnosed only if it is looked for. Tell your physician about your herpes to make sure he or she considers herpes as a possibility for your baby. You should not attempt to make your own diagnosis for your baby.

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