By Chris Tye

CHICAGO (CBS) — There has been a lot of confusion this week after a change in how positive cases of COVID-19 are being reported in Illinois. Friday there were more than 15,000 new cases — the highest day to day jump every in the country and three times where the state was a month ago. The governor describes it as a crisis level.

The state changed how it calculates new cases one week ago, adding cases that were not included before. Until last Friday the state calculated its “confirmed new cases” using only lab confirmed cases using molecular testing. Now, at the direction of the Centers for Disease Control and Prevention, the state is including probable cases, which includes rapid tests. Some are concerned those are more susceptible to false positives, creating higher numbers.

More clinically speaking: probable tests meet clinical criteria and are epidemiologically linked. It could also mean a positive antigen test.

Illinois’ top doctor, Dr. Ngozi Ezike with the Illinois Department of Public Health, says probable tests are 90% reliable.

“Are there a few cases in which it won’t be perfect? Yes,” she said. “That’s true, but that doesn’t mean that you’re going to throw away a positive pregnancy test and say that there’s no way you could be pregnant, so I think people just need to wrap their arms around this test and understand it’s a very good test.”

“This idea that we’re piling on tests and trying to make it look — listen. Nobody wants to have more positive tests showing up in the state of Illinois,” said Gov. JB Pritzker. “What we do want to know though is if people are positive.”

In Friday’s news of more than 15,000 new cases 1,050 are from the new probable side of the ledger. remove them and the total new cases would bee more than 14,000 — still a stunning number.

The governor and Ezike said they get asked all the time what they are doing to keep people safe.

She said people need to take ownership.

No stay-at-home order was announced, but the governor said hospitals are not overrun but the trajectory is troubling.


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