'Hidden Outbreaks' Hit IL Earlier Than Previously Known: Report

CHICAGO, IL — Hidden outbreaks of coronavirus were spreading through cities including Chicago, New York, Boston San Francisco and Seattle long before testing confirmed cases of COVID-19, according to research from Northeastern University shared with the New York Times.

Even in early February, when the world's focus was on the coronavirus outbreak in China, a model created by researchers shows the virus was likely spreading in multiple American cities.

Chicago's first confirmed coronavirus case — the second confirmed in the United States — was diagnosed in a woman in her 60s in late January. Her husband was also infected. Both recovered from the illness and were released from home isolation in mid-February.

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As of March 1, five major U.S. cities had only 23 confirmed cases. By March 2, Illinois officials said the state had four confirmed cases. In reality, the numbers were likely much higher, according to the Northeastern University model, which shows about 3,300 cases in Chicago at that time, according to the New York Times.

New York, which confirmed its first coronavirus case on March 1, probably had closer to 10,700 cases under the model.

In February, long before school closures were issued — Illinois' was announced March 13 — and stay-at-home or shelter-in-place measures were enacted, "little or no systematic testing for the virus was taking place," the New York Times reported.

"Meanwhile, in the background, you have this silent chain of transmission of thousands of people," said Alessandro Vespignani, director of the Network Science Institute at Northeastern University in Boston, who led the research team.

In California's Bay Area, there is more evidence coronavirus was spreading before the public was aware. A patient who died Feb. 6 is now believed to be the county's first coronavirus death. Two other people also died before what was previously thought to be the area's first coronavirus death on March 9.

Because not everyone who is sick gets tested — those who are well enough to manage their symptoms at home are advised to do just that — the numbers of coronavirus cases in the U.S. and Illinois are still likely much higher than the official numbers. Gov. J.B. Pritzker has acknowledged the need for more testing, as well as the fact that daily testing numbers are still far below what is ideal.

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As of Thursday, there were 36,934 confirmed cases of coronavirus in Illinois and 1,688 deaths. By Friday morning, there were 869,172 confirmed coronavirus cases in the U.S., hundreds of thousands higher than earlier coronavirus "hotspots" including China, Italy and Spain. Nationwide, nearly 50,000 people have died of coronavirus.

Illinois' stay-at-home order will be extended through May 31, with some modifications allowing some state parks and non-essential businesses to reopen.