Feasibility of Influenza Immunization for Inner-City Children Aged 6 to 23 Months

Abstract

Background: Annual influenza-related hospitalization rates of children aged <2 years in the United States are second only to those of the elderly. Yet no recommendations existed for vaccinating healthy children aged 6 to 23 months until 2002, when the Advisory Committee on Immunization Practices encouraged influenza vaccination for them. This study tested the feasibility of vaccinating 6- to 23-month-old children against influenza and assessed the effect on timely receipt of other vaccines. Methods: A pre–post trial was used in urban health centers serving low-income children. Sites selected interventions from strategies proven to increase vaccination rates. Targeted patients were aged 6 to 23 months by November 30, 2002 (N=1534). Results: Influenza vaccination rates for the 2002–2003 intervention season improved significantly from 6.5% to 38.5% for the first dose (p <0.001). Second-dose rates were significantly improved over preintervention (1.9% preintervention, 13.2% intervention), but lower than first-dose rates. Mean ages at vaccination for other recommended childhood vaccines did not differ or were significantly younger (measles, mumps, and rubella vaccine [MMR] and varicella) for children who received influenza vaccine versus those who did not. Moreover, a higher percentage of influenza-vaccinated than unvaccinated children received MMR, diphtheria, tetanus, pertussis vaccine 3 (DTaP3), inactivated poliovirus vaccine 2 (IPV2), and Haemophilus influenzae b (Hib2) vaccines within a 2-month grace period of the recommended age (p <0.039), with no differences between groups for Hib1, DTaP1, IPV1, and varicella. Conclusions: With directed effort, it is possible to increase influenza vaccination at health centers serving low-income children. The addition of a two-dose vaccine was not associated with delayed receipt of other vaccines among these children.