WASHINGTON — Expanding the traditional window for influenza immunization would add vaccination opportunities by increasing the number of pediatric office visits, based on data for 77.6 million children from a nationwide survey during the 2004-2005 flu season.
By expanding the vaccination window 6 months, either earlier or later, the overall number of children aged between 0 and 18 years with at least one provider visit jumped from 11.1 million to 23.4 million (July through December) or to 18.2 million (October through March), Dr. Richard G. Judelsohn reported in a poster at the jointly held annual Interscience Conference on Antimicrobial Agents and Chemotherapy and the annual meeting of the Infectious Diseases Society of America. The study was sponsored by MedImmune LLC, which makes Flumist nasal influenza vaccine. Dr. Judelsohn's coauthors are employed by MedImmune.
In early 2008, the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices expanded its recommendation that all children aged 6 months to 18 years receive the seasonal flu vaccine each year. However, many children do not visit a health care provider during the traditional flu vaccine window—October through December. The need for additional office visits for the vaccine could be a barrier to increasing flu vaccination.
For this study, the researchers used data from the Medical Expenditure Panel Survey, which is a federally funded survey of families, medical providers, and employers nationwide. Data from the 2004-2005 flu season was used to assess the number of children with existing medical provider office visits during specific monthly intervals. In particular, the researchers identified the number of children with one or more provider visit for various intervals by adding 1, 2, or 3 months before or after the typical flu vaccination window of Oct. 1-Dec. 31.
The researchers also looked at the data for five distinct age groups: less than 12 months, 12-23 months, 2-4 years, 5-8 years, and 9-18 years. Well visits were summarized separately from other provider visits because these may represent the greatest yield vaccination opportunity.
“With expansion of the traditional vaccination window, the largest percentage increase in the number of children with a provider visit is seen in children 5-18 years of age,” wrote Dr. Judelsohn, a professor of pediatrics at the State University of New York at Buffalo, and his coinvestigators. The percentage jumped from 27% between October and December to 46%-48% having a visit during either 6-month window.
“Overall, the proportion of children with existing visits decreases with increasing age,” they wrote. In all, 59% of children younger than 23 months had a visit between October and December, compared with 27% of children aged 5-18 years. Among children with a visit, the proportion with well child visits also decreases with increasing age.
ELSEVIER GLOBAL MEDICAL NEWS