Masks are required in all Pennsylvania public and private schools.By Royce Jones

PHOENIX (AP/KDKA) — Arizona public schools without mask requirements were several times more likely to experience COVID-19 outbreaks than schools with mandates in place when the current school year began, researchers said Friday in an article published by a federal health agency.

The article published by the Centers for Disease Control and Prevention looked at the impact of mask requirements at K-12 district schools in Maricopa and Pima counties, the state’s two most populous counties.

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“The odds of a school-associated COVID-19 outbreak were 3.5 times higher in schools with no mask requirement than in those with a mask requirement implemented at the time school started,” the article concluded.

The authors included researchers from the CDC, Arizona State University and public health departments of the two counties, which include metro Phoenix and Tucson and which together account for over 75% of the state’s population.

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Earlier this week, the Allegheny County Health Department said there are currently five open outbreaks and six open clusters in schools across the county.

Health Department Director Dr. Debra Bogen said so far this month, more than 1,600 cases among children ages 5 through 18 have been reported in the county.

Masks are required in all Pennsylvania public and private schools, as well as child care facilities. The Department of Health order took effect Sept. 7.

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