By Natasha Brown

MONTGOMERY COUNTY, Pa. (CBS) — Schools with coronavirus cases could be forced to close on short notice under new Pennsylvania rules. Districts just reopening for in-person instruction are concerned.

The Montgomery County Board of Health ordered all schools to go virtual two weeks ago in light of spiking COVID-19 cases throughout the region. Schools are set to reopen on Monday with a new set of state guidelines in place.

“These new rules do apply to us,” Wissahickon School District Superintendent Jim Crisfield said.

The Wissahickon School District is preparing to welcome students back for in-person learning, but Crisfield says under the state’s new rules, schools could shut down abruptly depending on COVID-19 case counts.

“We are now obligated to count cases by school,” Crisfield said, “so now it’s by school, not by district or not by county, and now they have shared these tables depending on the school size if you have X number of cases in a 14-day period you have to close down for Y number of days.”

Under the new rules, public schools have to revert to virtual instruction once they record certain numbers of coronavirus cases. For a building with fewer than 500 students that number is five or more COVID cases over 14 days is recommended to close for two weeks. The metrics vary depending on the school size.

“One of the problems with this new rule, though, is that it’s going to be very little advanced notice to staff or parents when we have to close,” Crisfield said. “Let’s say on a given Tuesday we get three cases and that puts us over the count limit for that school then we’ll have to close the next day.”

Two-thirds of the Wissahickon School District’s 4,500 students will return to classes on Monday. The district has not seen any in-school transmissions as of yet and officials hope it stays that way as they try to reassure concerned parents.

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