Research Shows Many Coronavirus Cases Have No Known Source

PITTSBURGH (KDKA) — With coronavirus case numbers rising, the time for targeted closures has passed, especially when it’s been hard to pinpoint where infections are coming from.
“As we’re seeing an explosion of cases around the world and in the United States, and certainly in our area, I think the targeted restrictions get more difficult to be able to do,” says Dr. Nathan Shively, an infectious diseases specialist at the Allegheny Health Network.
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