Short-Term School Closings Don't Stop Flu

(December 31, 2009) - Closing schools for a couple of weeks during a flu outbreak (Read about "Influenza") doesn't stop the spread of the flu and in fact may make it worse, according to a new study. Closing schools for just a few weeks during a flu pandemic may increase infection rates and prolong an epidemic, say researchers in a study published ahead-of-print and online in the Journal of Public Health Management and Practice. The findings, developed from a series of computer simulations based on U.S. census data, indicate that schools may need to be closed for at least eight weeks in order to significantly decrease the spread of infection.

The value of school closures has been debated as a possible strategy to stem or slow the current H1N1 influenza pandemic. Indeed, hundreds of schools across the country have been closed at different periods during 2009 for fear the virus would spread more quickly if they stayed open.

"Although closing schools may seem like a reasonable way to slow the spread of flu, we found that it was not effective unless sustained for at least eight weeks after implementation," said study lead author, Bruce Lee, M.D., M.B.A. Closing schools quickly at the start of an outbreak was much less important than keeping them closed continually throughout the epidemic, he added.

According to study authors, short-duration school closures can increase transmission rates by returning susceptible students back to school in the middle of an epidemic when they are most vulnerable to infection.

The study also found that identifying sick students individually and keeping them from attending school had minimal impact on an epidemic. In addition, there were no significant differences between individual school closures and system-wide closures in mitigating an epidemic.