COVID-19

CHICAGO — The latest count of new coronavirus cases was jarring: Some 1,500 virus cases were identified three consecutive days last week in Illinois, and fears of a resurgence in the state even led the mayor of Chicago to shut down bars all over town on Friday.

But at the same moment, there were other, hopeful data points that seemed to tell a different story entirely. Deaths from the virus statewide are one-tenth what they were at their peak in May. And the positivity rate of new coronavirus tests in Illinois is about half that of neighboring states.

“There are so many numbers flying around,” said Dr. Allison Arwady, the commissioner of the Chicago health department. “It’s hard for people to know what’s the most important thing to follow.”...

When the coronavirus pandemic began, public health experts had high hopes for the United States. After all, the U.S. literally invented the tactics that have been used for decades to quash outbreaks around the world: Quickly identify everyone who gets infected. Track down everyone exposed to the virus. Test everyone. Isolate the sick and quarantine the exposed to stop the virus from spreading.

The hope was that a wealthy country like the United States would deploy those tried-and-true measures to rapidly contain the virus — like quickly dousing every ember from a campfire to keep it from erupting into a forest fire.