Congenital Cytomegalovirus and Zika Infections

Congenital infections affecting newborn infants can have potentially devastating clinical outcomes. They are usually caused by viruses that infect mothers during pregnancy and are transmitted to the fetus or newborn during the prenatal, perinatal or postnatal periods. Congenital cytomegalovirus (cCMV) is the most common congenital infection affecting up to 2.5% of all live births. Even though most infected infants are asymptomatic at birth, cCMV is an important cause of neurodevelopmental impairment and represents the main cause of non-hereditary sensorineural hearing loss. Also, congenital Zika infection has emerged in recent years as a cause of microcephaly and neurodevelopmental delays. Currently, universal screening is not recommended for either infection in pregnant women or newborn infants. Therefore, screening for both conditions is based on multiple factors such as maternal immune status, exposure, and clinical manifestations of the infant. Use of antiviral medications on symptomatic cCMV has shown improvement in outcomes, in contrast with congenital Zika for which there are no therapeutic options available. Even though both viruses can be present in breast milk, there are no recommendations against breastfeeding in full-term infants. Close follow-up for affected infants is necessary to monitor for developmental delays and sensory impairments to implement interventional therapies at the earliest time possible.