HARRISBURG, Pa. (AP) — School closings began radiating farther from the Philadelphia area, with schools in at least 10 Pennsylvania counties closed Friday as the state mounted a sweeping social distancing measure aimed at slowing the spread of the COVID-19 outbreak.

Meanwhile, the number of positive tests grew from 22 to 33, the Department of Health said Friday, with more than 100 tests pending.

Montgomery County was the only one where all schools were closed. Gov. Tom Wolf on Thursday had ordered schools and other facilities closed in the suburban Philadelphia county of more than 800,000 people that has been hit hard by the outbreak, as he discouraged large gatherings of people statewide and canceled prison visits.

However, Wolf administration officials, in an online address to hundreds of school district officials Friday, said they are otherwise leaving the decision to close schools to districts and would try to speedily approve requests for flexibility to meet the requirement that schools be open for instruction 180 days each school year.

Some public schools in Allegheny, Bucks, Chester, Lancaster, York, Berks and Delaware counties were also shuttered for the day or longer, along with Allentown and Philadelphia. In the latter city, 63 schools were closed as a result of Wolf's order for Montgomery County because more than 2,000 of its 18,000 employees live in that county.

A look at the latest developments in Pennsylvania:

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CASES

All of the state's 33 cases of positive tests are in eastern Pennsylvania. Hardest hit is Montgomery County with 17 cases, with more new cases in Philadelphia and Delaware County reported Friday.

Dozens of tests are pending. Most confirmed cases involve someone who came into contact with the new coronavirus in another state or country, and most people are at home in isolation, not at the hospital.

For most people, the new coronavirus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia, and death.

The vast majority of people recover.

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MONTGOMERY COUNTY

Wolf has said his approach to Montgomery County will be continually evaluated. For now, it applies to all kinds of schools, including more than 20 public school districts in the county that educate more than 100,000 children. It also applies to higher education, day cares, adult care centers and private schools.

His administration said Wolf was acting under disaster emergency law that allows him to control movement and occupancy in a disaster area, but it could not say when a governor had last used that power. It also cited the Department of Health's legal responsibility to “determine and employ the most efficient and practical means for the prevention and suppression of disease.”

Gas stations, grocery stores, government facilities, utilities and mass transit should continue to operate, he said, while no-visitor policies are to be adopted by prisons and nursing homes.

For its part, Montgomery County officials are prohibiting all mass gatherings of any size that are outside, or in temporary structures, events that typically require a permit.

They also implored the cancellation of any nonessential public and private gathering indoors, and for businesses to allow employees to work from home.

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CANCELLATIONS

The Wells Fargo Center in Philadelphia said Thursday that it was canceling and rescheduling all events through March 31, while the Kimmel Center for the Performing Arts said it would cancel all events at its venues through April 11.

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PRISON VISITS

The state Department of Corrections has canceled all inmate visits for two weeks and said it will step up screening of employees and vendors, including taking temperatures and asking a series of questions. Anyone with flu-like symptoms or a temperature of 100.4 degrees or more will not be allowed in a state prison, Corrections Secretary John Wetzel said in a statement.

There are no confirmed cases in state prisons.

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This story has been corrected to show that new cases were also confirmed in Delaware County, not Delaware and Wayne counties.

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