More than half of the victims of a swine flu pandemic three years ago were school children and school closures proved to be a practical way to slow the spread of the disease, a study has found.
Between May and September 2009, 25,473 cases of influenza A (H5N1) were reported, forcing the closure of all kindergartens, primary schools and special schools, as well as secondary schools with many cases.
The study by Chinese University researchers found that the illness hit pupils at the start of the pandemic and spread to working adults and then younger children.
Elderly people were the least likely to be infected, and researchers speculated that they may have developed immunity in their younger days.
Reviewing the pattern of the outbreak, the researchers found that 54 per cent of those infected were pupils, and pointed out that cases involving children predominated during the first two weeks of the pandemic, in May.
'School-age children are usually the main transmitters of human influenza as a result of their high contact intensity with peers,' the study, published in the Hong Kong Medical Journal yesterday, said.
The researchers said that acting faster and closing all schools in a district, rather than individual schools where cases had been recorded, could theoretically be a more practical way of slowing transmission.
