Neonatal varicella.

Primary infection with varicella zoster virus (VZV) in the final 3 weeks of pregnancy may cause transplacental infection and neonatal varicella. Infants are most at risk of severe disease if born from 5 days before to 2 days after onset of the maternal varicella rash. Administration of post-exposure prophylaxis with varicella zoster immunoglobulin and treatment of varicella with aciclovir for those at highest risk of progression to severe disease is advised. Universal vaccination against VZV significantly reduces the incidence of neonatal varicella.