Understanding the Contagiousness and Transmission of Chicken Pox

10. Neonatal Varicella

If the mother acquires this infection within the last three weeks of her pregnancy, the virus passes through the placenta. The result is the infection of the child. In this case, the condition is called neonatal varicella. Neonatal varicella can also occur after birth. It's less likely to cause congenital anomalies, but it is still a serious condition. Neonatal varicella leads to death in one out of five newborn babies with the infection. Infection of the newborn is more dangerous when it occurs from five to 12 days of age. The good news is that neonates born to a vaccinated mother are protected from acquiring the infection.