BACKGROUND: Cytomegalovirus (CMV) infection continues to be an important occupational risk in the daycare setting. A comprehensive update of scientific evidence is timely to inform and promote appropriate preventive measures. METHODS: A review of the literature was conducted to examine the evidence for an occupational risk of CMV infection in daycare educators. Sources included Medline, government documents and additional references from published bibliographies. The key words used for searches were 'child day care centres' or 'nurseries' and 'cytomegalovirus' or 'cytomegalovirus infection'. RESULTS: Eight CMV seroprevalence studies on daycare educators in industrialized countries were found: four in the United States, three in Canada and one in Italy. Risk factors for seropositivity were older age, nonwhite race, foreign birth, birth in a low-or middleincome country, diaper changing, having children at home, and a child to educator ratio greater than 6:1 in children 18 to 35 months of age. Risk factors for seroconversion were younger age and working with young children. These studies suggest that daycare centres may be a high-risk setting for CMV infection. DISCUSSION: Recommendations to prevent CMV infection in this setting include handwashing, selective serological screening, avoiding work with younger children if pregnant and, in some cases, preventive leave from work. Evaluation and expert opinion of the effectiveness of various preventive options for CMV acquisition are needed to ensure that recommendations are evidence-based.