CHICAGO (Reuters) - Inoculating children against flu protects more people of all ages in the larger community, probably because young people tend to spread viruses through physical play, Canadian researchers said on Tuesday.

Researchers at McMaster University in Hamilton, Ontario found there were 61 percent fewer flu cases in isolated communities where children and adolescents received the seasonal influenza vaccine, compared to communities where children received an unrelated vaccine.

Targeting children with a vaccine could protect the wider population, researcher Mark Loeb and colleagues concluded in their report in the Journal of the American Medical Association.

Influenza struck 2,326 unvaccinated collaborators in the 46 religious Hutterite communities in western Canada that were chosen for study because they have limited outside contacts.

In communities where roughly four out of five children aged 3 to 15 were vaccinated, 3.1 percent of the people got the flu compared to a 7.6 percent infection rate in communities where no one was vaccinated against flu.