Child's Flu Shot Helps Whole Family

Mar. 23 --

FRIDAY, Sept. 7 (HealthDay News) -- Getting the flu shot for a young child protects both the little one and his or her family from getting sick this season, research shows.

In fact, if half of U.S. children between six months and five years old got their flu shots, more than 2,000 hospitalizations and up to 650,000 outpatient visits due to flu could be prevented.

"We found that only 12 to 42 children need to be vaccinated to directly preventone outpatient visit for the flu," study author Dr. Elizabeth Lewis, of MassGeneral Hospital for Children, Boston, said in a prepared statement. "And since the vaccination of some children in a preschool or daycare setting also reduces the chance that unvaccinated children would be exposed to the flu virus, the effects of vaccination are probably even greater than we found."

The American Academy of Pediatrics currently recommends flu shots for all children in this age group. Older siblings and family members should also get the flu shot to keep younger children protected during flu season. Lewis points out that when children are vaccinated against the flu, they also provide protection for the older adults in their home.

The study assumed a moderate flu season and a good match between the flu vaccine and the flu strains for the year.

For the current study, the authors analyzed existing data from several sources reporting on flu-related outpatient visits or hospitalizations covering several flu seasons. These included years in which the flu season was relatively mild as well as those in which flu was widespread and caused more serious illness.

Each year's flu vaccine needs to be designed in advance, based on which strains of virus are anticipated to be prevalent in the coming year. Because the accuracy of that prediction varies, the effectiveness of the flu vaccine also varies from year to year. To account for that variation, the research team calculated results based on several potential rates of vaccine efficacy.

"If the match is better or the flu season is more severe, then more visits would be prevented," senior researcher Dr. Katherine Poehling, of Wake Forest University Medical Center, in Winston-Salem, N.C., said in a prepared statement. "This is a very conservative estimate. We only account for direct protection by the flu shot. We do not account for the indirect protection to other children and adults who are less likely to be exposed to the flu when persons around them are vaccinated. This tells us that flu shots are an effective means to prevent illness and doctor visits from the flu each winter."

Flu vaccines do not contain live viruses, so children are not at risk for getting the flu from the shot itself, the researchers said.

The study is published in the September issue of Pediatrics.

More information

To learn more about the flu vaccine, visit the U.S. Centers for Disease Control and Prevention.

SOURCES: Wake Forest University Baptist Medical Center, news release, Sept. 4, 2007; Massachusetts General Hospital for Children, news release, Sept. 4, 2007