Annual flu vaccination was recommended for preschool-age children in the United States beginning in 2006. A new study shows the idea has produced the intended result by lowering flu complications in toddlers and in older children.

The study, published Monday, compared the impact of the 2006 recommendation to flu complication rates in Canada, which did not make the recommendation to vaccinate preschoolers until last year. Researchers at Children’s Hospital Boston and McGill University looked at 114,657 emergency room visits for flu-like illness from 2000 through 2009.

They found that hospital visits among U.S. children age 2 to 4 were 34% lower compared with Canadian children. Even flu rates in U.S. children age 5 to 18 declined up to 18% compared with Canadian children.

Vaccinating young children against flu makes sense because they are the age group that is most likely to bring the illness into the home and transmit it to other family members. But it’s also possible that the new policy on vaccinating toddlers has led to more older children getting vaccinated, too, the authors said. The study appears in the Canadian Medical Assn. Journal.


Flu vaccine for the 2011-12 season is already available in most clinics and doctor’s offices.

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