High rates of transmission of and colonization by Streptococcus pneumoniae and Haemophilus influenzae within a day care center revealed in a longitudinal study.

Day care centers (DCCs) are unique settings where young children are at increased risk for colonization by pneumococci and Haemophilus influenzae. Although point prevalence studies in DCCs are frequent, only a few longitudinal studies on the dynamics of colonization have been published. We conducted a 1-year longitudinal study with 11 sampling periods on nasopharyngeal carriage of pneumococci and H.