Confidential data shows thousands of undisclosed coronavirus cases in Illinois at schools, prisons, meatpacking plants and more

"Newly obtained confidential statewide data shows that coronavirus outbreaks in workplaces, schools and prisons are driving Illinois’ rising cases — and many of these outbreaks have never been made public," according to a joint investigation by Georgia Gee with Columbia University's Stabile Center for Investigative Journalism, Derek Kravitz with Columbia's Brown Institute for Media Innovation, and Sky Chadde with the Midwest Center for Investigative Reporting. 

State health officials said they refused to release the locations of many outbreaks because of state and federal laws meant to protect the identity of infected people. The same thing could be happening in other states.

Columbia's Documenting Covid-19 project and the Midwest Center obtained the internal data from the state health department, which covered four days between July and September, as part of an open-records request. The data gives detailed information and case counts for nearly 2,600 separate cases across the state. Federal, state and county prisons and jails are the single largest source of infections. That's largely driven by the Cook County Jail in Chicago, but there have been significant outbreaks at other prisons in rural areas such as Robinson Correctional Center in Crawford, Gee, Kravitz and Chadde report. Such outbreaks brought the total of prison cases to at least 3,500 as of Sept. 30—nearly double the figure reported by the Marshall Project and The Associated Press.