Objectives: To assess age-specific incidence rates, health care utilization, and lost parental work associated with varicella infection in a population-based cohort of children, and to validate parent-reported health care utilization data.
Study design: We conducted a telephone survey of a population-based cohort of 4557 households with children aged birth to 13 years. Medical chart abstraction was used to validate health care utilization information.
Results: We report varicella incidence rates in preschool children that are 2 to 2.5 times higher than previous studies. Rates of varicella-related serious complications, hospitalizations, parental work leave, and medication use are comparable with rates reported elsewhere. However, health provider visits occurred only 0.3 to 0.5 times as frequently as estimated in other studies. One hundred percent of reported hospitalizations and serious complications and 92% of provider visits were validated to be within the study time frame through medical chart audits.
Conclusions: Parents are an accurate source of varicella-related health care utilization data. Parent-reported incidence data indicate that varicella infections are increasing in preschool children. This shift to infections in younger children may be related to the increased use of out-of-home care for infants and young children. Furthermore, the shift may after the community burden of varicella because of the observed increased parental work loss and decreased frequency of health care visits in the preschool children.