Implementation of rotavirus immunization in Philadelphia, Pennsylvania: High levels of vaccine ineligibility and off-label use

OBJECTIVE. Our goal was to predict, using delayed diphtheria-tetanus-acellular pertussis vaccination as an indicator, whether the current narrowly defined age limits for pentavalent rotavirus vaccine exclude a substantial proportion of children from complete immunization against rotavirus and to assess adherence of providers to recommended age limits by examining the first 6 months of use of pentavalent rotavirus vaccine in Philadelphia, Pennsylvania. PATIENTS AND METHODS. Data from a computerized children's immunization registry in Philadelphia were analyzed. Demographics and age at immunization with first 3 diphtheria-tetanus-acellular pertussis doses were examined from 2001 to 2005. Similar characteristics were evaluated for children who received pentavalent rotavirus vaccine doses during the first 6 months of its availability (August 2006 through January 2007). RESULTS. During the 5-year period, 24 403 of 103 967 recipients of first diphtheria-tetanus-acellular pertussis vaccine were > 12 weeks of age; only 56 411 of 79 564 first diphtheria-tetanus-acellular pertussis recipients <= 12 weeks of age received the first 3 doses at ages that they could have completed the pentavalent rotavirus vaccine series if vaccines were given at the same visit. Children using public providers were more likely to have delayed immunization. During the first 6 months of pentavalent rotavirus vaccine implementation, 5566 pentavalent rotavirus vaccine doses were recorded in the Kids Immunization Database/Tracking System: 3912 first doses, 1419 second doses, and 235 third doses. Of 3912 first-dose pentavalent rotavirus vaccine recipients, 770 were > 12 weeks of age. Hospital-based providers were less likely to administer pentavalent rotavirus vaccine off-label. CONCLUSIONS. With the current level of vaccine implementation and current pentavalent rotavirus vaccine recommendations for series initiation, a substantial proportion of children are expected to be excluded from receiving any pentavalent rotavirus vaccine or completing the series. In the first 6 months of availability, pentavalent rotavirus vaccine frequently was used off-label for age, underscoring the importance of education of immunization providers. Current outreach programs for finding 10-month-old toddlers delinquent for immunizations will not improve the possibility of protection against rotavirus.