Cytomegalovirus infection in day care centres: A systematic review and meta-analysis of prevalence of infection in children.

Maternofetal transmission of cytomegalovirus (CMV) is the most common infectious cause of congenital malformation in developed countries. Maternal infection often results from close contact with infected children, and this may occur in day care centres (DCCs). A systematic review of observational studies was conducted to examine the prevalence of CMV infection among children attending DCCs. Meta-analysis using the random effect model was performed for studies including controls. Sources included PubMed, EMBASE (until August 2018), and references from identified publications. Inclusion criteria were studies reporting CMV infection prevalence among childcare children aged less than 7 years of age. Controls were children without childcare exposure. CMV infection was defined as viral excretion detected by culture, polymerase chain reaction, or CMV seropositivity. Twenty-eight publications including 8347 participants met the eligibility criteria. The pooled prevalence of CMV infection among children in childcare from all studies was 32% (95% CI 23-41). Within case-controlled studies, prevalence among children attending DCCs was 34% (95% CI 25-44), whereas prevalence among those without childcare exposure was 22% (95% CI 15-30). Meta-analysis showed a significant association between DCC attendance and CMV infection (odds ratio 2.69, 95% CI 1.68-4.30; heterogeneity χ2 /df = 8; I2  = 84%, P < 0.00001). Attendance at DCCs is significantly associated with increased risk of childhood CMV infection. Prevention strategies to reduce risk of CMV infection of pregnant women and children should involve review of DCC exposure and consideration of preventative hygiene strategies.