Infants aged less than 1 year who initiated a rotavirus vaccine series between 01 January 2009 and 30 June 2009 were identified in US health insurance claims data. Cohorts were formed based on vaccine brand use. Series completion and compliance with the FDA-approved and ACIP-recommended harmonized schedules were analyzed descriptively and a log binomial model was used to estimate the difference in series completion by vaccine brand while adjusting for demographic variables.
Among infants in the RV1 and RV5 cohorts (N = 55,584), 84.3%completed a full series. A greater proportion of the RV1 cohort than the RV5 cohort completed their series (91.0%vs. 83.4%; P < 0.001; multivariate-adjusted relative risk 1.07; 95%CI 1.06-1.08). In the RV1 and RV5 cohorts, respectively, 75.0%and 59.5%of infants were fully compliant with the FDA-approved administration schedule for their vaccine (P < 0.001); 83.3%and 76.4%of infants were fully compliant with the harmonized schedule (P < 0.001).
The proportion of infants that completed the series was greater and compliance with respective FDA-approved and harmonized dosing schedules was higher among infants vaccinated with RV1 than among infants who received RV5.