 Cytomegalovirus CMV is the largest member of the virus family Herpesviridae that infects almost all humans at some point in their lives Ross, 2004. Congenital CMV infection is most likely to occur when the mother experiences a primary infection during pregnancy, and it is much less common in cases of reactivation of the disease or infection by a different CMV strain Boppana 1999, Endres 2001. The prevalence of congenital CMV infection varies between 0.15-2.2 Ross 2004, Ross 2006, Malm 2007. While most infants born with congenital CMV infection are asymptomatic, 10 to 15 show clinical findings at birth Ross 2004. 