By Jan Carabeo

MONTGOMERY COUNTY, Pa. (CBS) — It’s time to wear your mask again in four local school districts. Norristown, Cheltenham, Lower Merion, and Lower Moreland schools are telling students and staff to wear them in the classrooms and on the buses.

“Please remember to send your child to school with a mask. If your child doesn’t have a mask, they are available in the nurse’s suite. Once the county has returned to ‘medium’ on the data tracker, the district will pivot back to ‘mask recommended.’ We are still offering Test to Stay and Mask to Stay for eligible students and staff,” Cheltenham Superintendent of Schools Dr. Brian Scriven said in a letter sent to parents.

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When kids get on the bus and step inside school in the Lower Merion School District Friday, they will once again need to wear a mask. 

The district announced the move Thursday night saying that Montgomery County has moved into what’s called a “high COVID community level.”

What does that mean?

Well, that “high COVID level” is designated by the CDC, and Lower Merion has aligned its masking policy with those metrics. 

It means Montgomery County has:

  • More than 281 cases per 100,000 people.
  • More than 10 hospital admissions per 100,000 people.
  • And that 3.4% of inpatient hospital beds are in use by COVID patients.
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So, generally, it means both case numbers and hospitalizations have increased in the county.

Nationwide about one-third of the country lives in areas where COVID infections are at medium or high-risk levels.

New cases are nearing 100,000 per day. Cases are up in 41 states, and hospitalizations are on the rise in 40 states.

Health experts say the situation is likely worse. 

“The reality is much worse because we’re undercounting COVID cases,” Dr. Celine Gounder, of Kaiser Health News, said. “Many people are testing at home using at-home rapid tests, and many people are not testing at all.  

Lower Merion isn’t alone. The Norristown, Cheltenham and Lower Moreland School districts are also returning to masks for all students and staff. 

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Meantime, Philadelphia is still at the medium community level.