New hospital standards needed for pediatric flu vaccines

February 4, 2008

A new study published in the February 2008 issue of Pediatrics finds that many children hospitalized for influenza have had a recent, previous hospitalization that would have provided an easy, convenient opportunity to receive a hospital-based influenza vaccination. The authors suggest that evaluating and establishing industry standards for flu vaccines for hospitalized children could help prevent additional hospitalizations and complications from influenza.

In the peer-reviewed article “Hospital-Based Influenza Vaccination of Children: An Opportunity to Prevent Subsequent Hospitalization,” the research team led by Danielle M. Zerr, MD, MPH, medical director of infection control at Seattle Children’s Hospital and associate professor of Pediatrics at the University of Washington School of Medicine (UWSOM), evaluated the frequency of previous hospitalizations among children hospitalized with influenza.

Overall, they found that 23% of children hospitalized with influenza and another complicating illness had a previous hospitalization during the most recent flu-vaccine season. This suggests that reaching those children at highest risk for influenza complications and reducing rates of pediatric hospitalization for influenza may be aided by providing in-hospital vaccinations when children are hospitalized during flu vaccine season.

The study looked at five years of hospital discharge data from the Pediatric Health Information System (PHIS) database from 2001 through 2006 to determine how many children hospitalized with influenza or respiratory illness had a previous hospitalization during the most recent flu-vaccine season. PHIS is an administrative database developed by the Child Health Corporation of America (CHCA), used by 42 free-standing pediatric hospitals. Subjects included newborns through age 18. A previous hospitalization during flu vaccination season was considered if it occurred in the two weeks to six months prior to the influenza admission and between September 1 and March 1. Approximately 14,000 cases of children hospitalized with influenza and 170,000 hospitalized with influenza or a respiratory illness were reviewed.

Researchers found approximately 16% of those hospitalized with influenza and 23% of those hospitalized with influenza and another underlying condition had previous hospital admissions during the vaccination season.

“This information will help pediatricians recognize hospitalization as an important opportunity to vaccinate the highest-risk children, and may hopefully prompt the development of hospital-based flu vaccine programs,” said Zerr.

Influenza is a highly contagious illness causing an average of 36,000 deaths and 200,000 hospitalizations per year in the United States; pneumonia is the most common complication in high-risk groups. Young children and those with certain health conditions are at high risk for serious flu complications.

Influenza, unlike the common cold, has a swift onset of severe symptoms beginning with two to seven days of fever, headache, muscle aches, extreme fatigue, runny nose and sore throat, and a cough that is often severe and may last seven days or more. The flu season is generally from November to April, with most cases occurring between late December and early March.

In 2007 the Centers for Disease Control and Prevention Advisory Committee on Immunization Practices recommended that unvaccinated patients of all ages (including children with high-risk conditions) and all persons aged 6 months to 4 years as well as those 50 and older who are hospitalized at any time, beginning from the time flu vaccine becomes available for the upcoming flu season and continuing throughout flu season, should be offered and strongly encouraged to receive influenza vaccine before being discharged from the hospital.

Seattle Children’s has had a long-standing aggressive flu prevention program, offering free flu shots to inpatients, outpatients and staff. In 2007-2008 Seattle Children’s also offered free vaccines to those with close contact with patients such as family members, teachers, day care staff, nannies and more.

“Many of the sickest children have very fragile immune systems. At Seattle Children’s we’ve already expanded our program beyond patients and staff to ensure we’re doing everything we can to reduce the risk of exposing our high-risk patients to the flu and its complications,” said Zerr. She adds “With findings from this study, we can see that an industry-wide review of hospital-based flu vaccines for all children could take flu-prevention to the next level.”

Source: Children's Hospital and Regional Medical Center of Seattle