Neonatal herpes simplex

Neonatal herpes simplex is a herpes simplex virus (HSV) infection in a newborn baby, mostly as a result of vertical transmission of the HSV from an affected mother to her baby. Types include skin, eye, and mouth herpes (SEM), disseminated herpes (DIS), and central nervous system herpes (CNS). Depending on the type, symptoms vary from a fever to small blisters, irritability, low body temperature, lethargy, breathing difficulty, and a large abdomen due to ascites or large liver. There may be red streaming eyes or no symptoms. The cause is HSV 1 and 2. It can infect the unborn baby, but more often passes to the baby during childbirth. Onset is typically in the first six weeks after birth. The baby is at greater risk of being affected if the mother contracts HSV in later pregnancy. In such scenarios a prolonged rupture of membranes or chilbirth trauma may increase the risk further. Globally, it is estimated to affect one in 10,000 births. Around 1 in every 3,500 babies in the United States contract the infection. Neonatal herpes manifests itself in three forms: skin, eye, and mouth herpes (SEM, sometimes referred to as "localized"); disseminated herpes (DIS); and central nervous system herpes (CNS). SEM herpes is characterized by external lesions but no internal organ involvement. Lesions are likely to appear on trauma sites such as the attachment site of fetal scalp electrodes, forceps, or vacuum extractors that are used during delivery; in the margin of the eyes; in the nasopharynx; and in areas associated with trauma or surgery (including circumcision). DIS herpes affects internal organs, particularly the liver. CNS herpes is an infection of the nervous system and the brain that can lead to encephalitis. Infants with CNS herpes present with seizures, tremors, lethargy, and irritability. They feed poorly, have unstable temperatures, and their fontanelle (soft spot of the skull) may bulge. CNS herpes is associated with higher morbidity, while DIS herpes has a higher mortality rate.