CDC urges flu vaccination for all children

The Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP), which advises the CDC on vaccine issues, voted Feb. 27, 2008, to expand the recommended ages for annual influenza vaccination to include all children from 6 months through 18 years of age. The expanded recommendation is based on clinical evidence that the burden of influenza illness is high in children and that prevention of influenza in children can decrease disease in household contacts as well as in the community at large.

The goals of the newly expanded recommendations are to reduce the costly influenza-related morbidity in the entire population and reduce the mortality seen in the elderly, which has continued to climb despite high vaccination rates in this high-risk population.

Yearly seasonal influenza epidemics are responsible for approximately 226,000 hospitalizations and more than 36,000 deaths annually in the United States. In a recently completed economic analysis, the CDC projected that the total burden of annual epidemics amounts to $87.1 billion, which includes costs associated with life-years lost, ≥ 31 million outpatient visits, approximately 3 million days of hospitalization, and time lost from work. Although the majority of influenza-related deaths occur in the elderly, young children, especially those under 2 years of age, have hospitalization rates similar to those of the elderly. In addition to inpatient utilization, studies have shown that for every 100 children an annual average of 6 to 15 outpatient visits and 3 to 9 courses of antibiotics can be attributed to the influenza virus.

A clinical study performed in central Texas demonstrated that vaccinating 20% to 25% of the school-aged population resulted in an 8% to 18% decrease in the number of medically attended respiratory infections in adults in the community. In a recent school-based trial reported in the New England Journal of Medicine, influenza-related disease outcomes were compared among children who were vaccinated with influenza vaccine with children in control schools where influenza vaccine was not offered. Members of intervention-school households (children and adults) had significantly fewer influenza-like symptoms. Similarly, there were significant differences between groups with respect to the use of prescription and over-the-counter medicines, visits by children to doctors or clinics, absentee rates from school, and workdays lost by parents to care for their own or someone else's influenza-like illness. A companion pharmacoeconomic evaluation examined the cost consequences of mass vaccination of children in schools and showed that vaccination not only reduced the number of households that experienced influenza-like illness but that it could also be cost-saving.

Two types of influenza vaccine-inactivated and live attenuated-are currently licensed for use in children. Each vaccine is formulated to protect against the three strains of influenza viruses recognized by the CDC and World Health Organization as the current year's circulating wild type virus. Both vaccines are similarly well tolerated in eligible individuals. There are currently five branded inactivated influenza vaccines, which are all administered by intramuscular injection. Some products are indicated for infants as young as 6 months while others have a more restricted age indication. One live attenuated influenza vaccine is currently available as an intranasal spray for use by those 2-49 years of age.

By expanding influenza vaccination recommendations to include all children through the age of 18 years, the CDC hopes to further reduce the burden of influenza. Mass vaccination programs aimed at children (e.g., school-based programs) may be the most cost-effective manner by which to reduce the burden of influenza in the community. Managed care organizations should expect increased utilization of influenza vaccinations in children in the coming years and may wish to consider options to promote mass vaccination of school-aged children against influenza. The hope is that by fully implementing the new CDC guidelines, overall healthcare cost resulting from influenza disease could decrease in all groups, including the elderly.

J. BAUMAN, PharmD, is president, scientific and technical evaluation for Pharmaceuticals, Inc.

FINANCIAL DISCLOSURE: Dr. Bauman is a consultant to MedImmune and has received compensation for analyses and input on various projects concerning FluMist and Synagis including this article.