Neonatal herpes is a viral infection affecting newborns, caused by the herpes simplex virus (HSV) – the same virus responsible for cold sores and genital herpes in adults. This article explores how infants acquire neonatal herpes, its nature, and whether an infected infant can spread it.
Understanding Neonatal Herpes
The herpes simplex virus (HSV), primarily HSV-1 or HSV-2, can be acquired by a baby in several ways. The most common route, accounting for approximately 85% of cases, occurs during vaginal delivery when the baby contacts the virus in the mother’s birth canal. This risk is elevated if the mother experiences a new genital herpes infection in late pregnancy, as she may not have developed protective antibodies to pass to the baby.
About 10% of neonatal herpes cases are acquired after birth, known as postnatal transmission. This can happen if a newborn is exposed to someone with an active herpes lesion, such as a cold sore, through direct contact like kissing. In rare instances, less than 5% of cases, the virus can be transmitted to the fetus while still in the womb via the placenta or cervix.
Contagion and Transmission from Infants
Yes, neonatal herpes is contagious from an infected infant. The herpes simplex virus is highly transmissible through direct contact with active lesions or infected bodily fluids. An infant with active neonatal herpes can spread the virus to others, including caregivers and family members.
Transmission from an infected infant occurs through direct contact with fluid-filled blisters on their skin, around their eyes, or in their mouth. The virus can also spread through contact with infected secretions, such as saliva or tears. For instance, if an individual touches an infant’s active lesion and then touches their own eyes, mouth, or broken skin, the virus can be transferred.
Careful hygiene practices are important to prevent the virus’s spread from an infected infant. This includes thorough and frequent hand washing, especially after touching the baby or changing diapers. Anyone with active herpes lesions, such as cold sores, should avoid direct contact with newborns and cover any lesions, washing hands meticulously if contact is unavoidable.
Recognizing the Impact on Infants
The signs and symptoms of neonatal herpes vary depending on which body parts are affected. Symptoms often appear between 6 to 11 days after birth. The infection can manifest in three main forms: localized to the skin, eyes, and mouth (SEM disease); central nervous system (CNS) involvement; or disseminated disease, which affects multiple organs.
In SEM disease, infants may develop fluid-filled blisters on their skin, around their eyes, and in their mouth, though not all affected babies will have these visible blisters. If the virus affects the central nervous system, symptoms can include lethargy, irritability, seizures, poor feeding, and an unstable body temperature. These neurological signs may appear later, around 16 to 19 days after birth.
Disseminated disease is the most severe form, impacting organs like the liver, lungs, and adrenal glands, and can lead to symptoms such as jaundice, respiratory distress, and shock. Early diagnosis is important, as the infection can progress rapidly and cause serious health issues. Diagnosis involves testing samples from skin lesions, blood, cerebrospinal fluid, or other affected areas for HSV DNA using methods like viral culture or PCR testing.
Treatment and Prevention Strategies
Prompt treatment for neonatal herpes is important to improve outcomes and reduce complications. The primary treatment involves antiviral medications, with acyclovir being the most commonly prescribed. This medication is administered intravenously, directly into the baby’s vein, for a duration that depends on the infection’s severity and type.
For infections localized to the skin, eyes, and mouth, intravenous acyclovir is usually given for 14 days. If the infection has spread to the central nervous system or is disseminated, treatment may extend to 21 days or longer, sometimes followed by a six-month course of oral medication to prevent recurrence and improve neurodevelopmental outcomes. Early initiation of antiviral therapy, ideally as soon as the infection is suspected, is important for effective management.
Preventive strategies focus on reducing the risk of transmission from mother to infant. Pregnant individuals with a history of genital herpes should inform their healthcare provider, as they may be prescribed antiviral medication in the last month of pregnancy to suppress outbreaks. If active genital lesions are present at the time of labor, a Cesarean section may be recommended to avoid exposing the baby to the virus during birth.