“School closures can be disruptive and costly for families,” LWSD said in a statement, recommending schools not shut unless there were COVID-19 exposure risks.

The dilemma over whether to close schools has rolled into the United States as U.S. coronavirus cases top 200. The outbreak has had an unprecedented impact on schools worldwide, the education of over 290 million students affected in 13 countries, according to the United Nations.

Closures have long been a U.S. response to influenza, a dangerous and highly contagious disease for students. But health authorities are rethinking their approach for coronavirus, shown to have limited effects on children.

“Do we really want to close schools or do we want to keep schools open so faculty can continue to come in and serve children?” said Jeffrey Duchin, health officer for Seattle and King County.