Cold, Flu, & Cough Health Center

Preschool Kids Driving Flu Epidemics?

Flu Study

The new flu study comes from researchers including John Brownstein, PhD, of the emergency medicine division of Children's Hospital Boston and the pediatrics department of Harvard Medical School.

Brownstein's team checked medical records of flu patients at six Massachusetts health care settings, including hospitals and a large group medical practice, from January 2000 through September 2004.

Preschool-age children provided the first sign of pneumonia and influenza, the researchers report.

Flu season can begin as early as October and last as late as May, says the CDC.

In the study, 3- and 4-year-old children started showing up in hospitals and doctors' offices with respiratory illnesses as early as late September. Younger kids began arriving a week later, older children in October, and adults in November, states a news release.

In addition, respiratory illness in kids younger than 5 years old was a stronger predictor of death than in any other age group.

'Hotbeds of Infection'

"The data make sense because preschools and daycares, with their close quarters, are hotbeds of infection," says Brownstein in a news release.

The findings don't prove that preschool-age kids are the first victims or main spreaders of the flu, note Brownstein and colleagues. But "this age group does appear to have an important role in influenza transmission," they write.

The Advisory Committee on Immunization Practices is considering a recommendation to vaccinate all preschool-age children against the flu, and the study's results support that recommendation, write the researchers.