Congenital cytomegalovirus infection in the Netherlands: birth prevalence and risk factors.

Congenital cytomegalovirus (CMV) infection is the most common congenital viral infection worldwide. The sequela encountered most frequently is hearing impairment, affecting approximately one out of five infants congenitally infected. Data on the birth prevalence and risk factors of congenital CMV infection in the Netherlands are scarce. The aim of this study was to determine the birth prevalence of congenital CMV in the Netherlands. A sample of 6,500 dried blood spots (DBS) from infants born in the Netherlands was tested anonymously for CMV DNA. The sample was stratified by the number of live births in different regions of the Netherlands of the year 2007. Additionally, on a regional level, risk factors for congenital CMV were analyzed. The birth prevalence of congenital CMV in the Netherlands was 0.54% (35/6,433, 95%CI 0.36-0.72). Congenital CMV infection was significantly higher in regions with more than 15% young children (0-5 years) compared with regions with a lower proportion of young children (OR 5.9, 95%CI 1.4-25.2). Congenital CMV infection was significantly higher in regions with more than 30% immigrants compared with regions with a lower proportion of immigrants (OR 2.2, 95%CI 1.1-4.6). This association was strongest for regions with more than 30% non-Western immigrants (OR 3.3, 95%CI 1.5-7.5). Based on the knowledge of the natural history of congenital CMV infection, approximately 1,000 children are born with congenital CMV infection in the Netherlands annually, of whom eventually approximately 180 children (0.1% of all newborns) will be affected by long term sequelae, with hearing loss being the symptom encountered most frequently.