CHICAGO (CBS) —  A fourth person is diagnosed with the virus in the Chicago area.

CBS 2’s Vince Gerasole has more from the Thompson Center about the new cases.

A CDC task force is on the ground working with public health officials. A fourth patient, the wife of patient number three, has now tested positive for coronavirus, also known as COVID-19.

And from healthcare workers to those patients may have interacted with, 286 Illinois residents are being monitored at least twice a day because of potential exposure.

Illinois’ patient number four is a woman in her 70s who tested positive for COVID-19.  She is now under at-home isolation and in good condition according to the Illinois Department of Public Health.

She is married to patient number three. He is a man, also in his 70s, who tested positive over the weekend and is now in isolation at Northwest Community Hospital.

He is also said to be in good condition.

Doctors from Northwest Community Hospital are working with an onsite task force that includes infectious disease experts from the Centers for Disease Control as well as personnel from the Illinois Department of Public Health.

“All staff that has been identified as having any contact with this patient have been notified and are undergoing testing and monitoring,” said Doctor Daniel Reaven of Northwest Community Hospital.

“In cases this involves keeping health care workers at home who were in contact with the patients,” said Dr. Ngozi Ezike of the Illinois Department of Public Health.

The IDPH said there are currently 286 people in the state undergoing monitoring and twice daily testing who may have been exposed.

Elsewhere as a precaution, Arlington Heights School District 25 is notifying families that two workers and two students from four different schools have been asked to stay home. Each may have had contact community contact with a hospital worker who might have been exposed to a positive patient.

Illinois Governor JB Pritzker said Illnois’ numbers remain low and urges calm.

“The best thing the public can do is to take the same precautions you take at flu season,” Prizker said.

Pritzker said the state is not ready to release where this couple, patients three and four, may have been in the past few days, who they may have had contact with, whether they were on public transportation.

Click here for CBS 2’s Coronavirus Facts site for more information on the illness.

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Vince Gerasole