The University of Chicago Medical Center stated late Tuesday that the patient admitted to the hospital late Monday tested negative for coronavirus.
"We wanted to share news that the patient admitted for possible COVID-19 infection yesterday has tested negative for the disease," the statement read. "We would like to thank the clinical team who cared for the patient while we awaited test results from the Illinois Department of Public Health.
We remain committed to providing safe and effective care to those in our community who become infected with COVID-19. We will continue to work with federal, state and local health officials as we monitor the situation locally and nationally while also ensuring UChicago Medicine’s readiness for the various stages of the epidemic."
Hospital staff did not provide any further details on the patient.
If confirmed, this would have marked Cook County's fifth case of the coronavirus amid the global outbreak. State health officials announced Monday that a fourth patient in Illinois had tested positive for the virus.
The woman in her 70s is the spouse of a man, also in his 70s, who tested positive over the weekend in a Chicago suburb, the Illinois Department of Public Health said in a release.
Health officials said both patients were in "good condition." The woman was being quarantined at home and was "complying with health officials," they said.
"Public health officials are working to identify and actively monitor individuals who were in contact with both patients in an effort to prevent additional transmission," the Illinois Department of Public Health said in a statement. "Public health officials will reach out to individuals who may have been exposed."
Meanwhile, the hospital treating the woman's spouse said Monday that the person remains hospitalized in isolation.
Northwest Community Healthcare said infectious disease specialists are at the hospital "working closely with communicable disease officials from the Cook County Department of Public Health, the Illinois Department of Public Health and the CDC."
"NCH is closely following recommended guidelines outlined by these officials," the hospital said in a statement. "At the moment we are implementing all associated protocols, including an exposure investigation, to identify those who might have had contact with this patient in order to treat them accordingly. Along with this patient, our top priority will remain to keep our staff and community safe at all times."
The husband and wife have not been identified and additional details, including where or when they were exposed, weren't immediately available.
Though tests for the latest patient, which were conducted in Illinois, came back with positive results for COVID-19, the results for both cases have yet to be confirmed by the U.S. Centers for Disease for Control and Prevention, officials said.
Public health officials said they're working to identify and actively monitor individuals who were in contact with the patient in an effort to reduce the risk of additional transmission. The state of Illinois also plans to ask the CDC to deploy a team for assistance.
In January, two Chicago residents, a husband and wife, were diagnosed with the coronavirus. The wife had recently traveled to Wuhan, China, the epicenter of the outbreak, to care for a relative.
Both patients were treated at AMITA Health St. Alexius Medical Center in Hoffman Estates and have since made a full recovery.
At least six people have died in the U.S. from the coronavirus, with more than 90,000 cases and 3,100 deaths reported worldwide.
Last month, Illinois became the first state to conduct its own tests for the coronavirus, allowing for quicker results.
At a news conference Friday, Gov. J.B. Pritzker said as a precautionary measure, the state will expand to two additional testing labs in central and southern Illinois in the coming week.
On Monday, officials said Pritzker requested that hospitals across the state implement additional testing to "improve surveillance for COVID-19."
The Illinois Department of Public Health launched a statewide hotline for the coronavirus, also known as COVID-19, "to answer any questions from the public or to report a suspected case," Pritzker said. That number is 1 (800) 889-3931.