Rock County’s first confirmed case of COVID-19 announced Thursday evening is a support services employee for Mercyhealth, according to a Friday morning news release.

The employee is quarantined at home with mild symptoms and is recovering, according to the release.

The 57-year-old person works at the Michael Berry Building on the Mercyhealth Hospital and Trauma Center campus in Janesville.

The health system confirmed the employee had no contact with patients, according to the release.

Officials Thursday night were careful not to say where the person lives or other personal details out of privacy concerns, but at one point in a telephone conference one department official referred to the person as female.

The Rock County Public Health Department in a release Thursday announced the person who tested positive recently traveled to an event in Chicago.

It is “highly likely” the person was exposed to the disease at an event out of state, according to the Mercyhealth statement.

Mercyhealth is following Centers for Disease Control and Prevention guidelines and taking “every precaution necessary” to ensure health and safety of patients, visitors and staff, according to the release.

“Every COVID-19 case underscores the need for all of us to stay vigilant in the face of the virus, while offering support and care to all those who need it in our community,” the release states.

The health department is working to identify and contact any people who have been in close contact with confirmed cases.

The Rock County woman was tested Monday, and the health department received notification from a state disease surveillance system Thursday, officials said.

Among the many questions officials couldn’t answer Thursday were whether the woman had traveled with anyone to Chicago, what symptoms the woman had, why she was tested, whether anyone else lives in her home and how long she might be in isolation.

Rock County Health Officer Marie-Noel Sandoval said she expected Rock County will see more cases.

Officials all week have advised Rock County residents to act as if there were active cases of COVID-19 in the community, regardless of if positive cases were announced.