How and when to close schools?

About a month ago we posted on some syndromic surveillance work from Boston Children's Hospital suggesting the drivers of influenza pandemics might be school aged children. Respiratory disease in the 3 to 18 year age group shows up about a month earlier than in adults. It may be that they are only heralds of an outbreak, not the drivers of it, but the idea that children are especially good spreaders of influenza has plausibility. It raises at least two questions, one related to vaccination strategy (covered in the earlier post) and the other to the problem of school closings. In the just concluded Geneva conclave of flu experts, one of the strong recommendations was that there be plans for when to close schools.

This is an especially knotty problem because schools function not only to educate children but to care for them as well while their parents are working. When school is closed this places a special burden on parents to find alternative child care arrangements (which may themselves be problematic from the epidemiological point of view) or stay home themselves. If the Boston data are correct, we would want to close the schools when an outbreak is threatened, not after it is underway. They could be closed, for example, as soon as the first confirmed case is diagnosed in the region, or some similar strategy.

But so far there has been little progress in solving the difficult inter-related problems school closings entail. The federal government has punted, leaving everything (including how to figure it out) up to local school boards:

No national plan exists that tells schools how to protect students in case of a bird flu epidemic. Schools are looking to local health departments for guida"We're scrambling just like everybody else," said David Griffith, spokesman for the National Association of State Boards of Education. "You don't want to be slow because when the genie's out, the genie's out."

The best defense may be to close a school so sick students don't spread the flu to others, he said, citing the advice of health experts.

A national plan isn't expected because local authorities make decisions such as when to close a school and how to notify parents, said Susan Wooley of the American School Health Association in Kent, Ohio.
Officials are re-examining school closure policies. Usually, they close if 10% of the children or teachers call in sick, Wooley said.

[snip]

The Department of Health and Human Services has prepared an overall national plan, which wouldn't specify what schools should do but urges them to prepare their own plans.

The Department of Education might issue guidelines that schools can choose to follow. (Gannett, by-line Raju Chebium)

Notice to the Department of Education: your assignment is due.