CHICAGO (CBS) — Starting Wednesday morning, visiting patients at The University of Chicago Medical Center will be a bit more difficult. As flu season picks up, the hospital won’t allow children under 12, or anyone having a fever, cough or runny nose to enter as a visitor.

“It’s not for the sake of being mean-spirited, it really is for the health and safety of our patients,” said Dr. Allison Bartlett, assistant professor of pediatric infectious disease at U. of C. Medicine.

Visitation at the hospital has been restricted during every flu season since 2011, she said, but this is the first time it has happened this early.

Bartlett said restrictions normally go into effect after Jan. 1, but that the timing is based on when the hospital reaches its “threshold for influenza activity.” The threshold is based on how many patients with flu symptoms are kept in the hospital overnight.

“Once we have more than a handful of patients admitted for the flu, we make a judgement call that triggers our decision,” she told the Sun-Times.

Dr. Julie Morita, Commissioner of the Chicago Department of Public Health, said 22 people in Chicago have been hospitalized for flu symptoms in the Intensive Care Units at several hospitals since October. She said that although it’s hard to predict how severe this flu season will be, the number of reported cases has spiked in the past few weeks, and “people’s risk for influenza is definitely increasing.” She said it’s not too late to get a flu shot.

According to Bartlett, anyone with flu-like symptoms won’t be allowed to visit U. of C. because even if their symptoms are mild, they could hit a sick patient much harder.

Children under 12 will be restricted because they can’t always identify their symptoms, and they carry or “shed” the flu for longer periods of time, Bartlett said. Children may be contagious days before they show symptoms, and for days or even weeks after their symptoms are gone, she said.

Northwestern Medicine does not have visitor restrictions at any of its hospitals.

Rush University Medical Center hasn’t placed any restrictions yet, but “that could literally change any minute,” said Dr. Alexander Tomich, director of infection prevention and control.

Tomich said the hospital has seen a spike in patients reporting flu symptoms since early last week. The hospital passed its threshold for high flu activity early last week, when more than 10 percent of patients visiting the emergency department reported flu symptoms, Tomich said.

He said any restrictions placed on visitation at Rush in the past have been geared toward children.

According to Tomich, restricting younger visitors is a win-win for slowing the spread of the flu. By keeping kids out of hospitals, fewer patients contract the virus from sick kids, and fewer young visitors pick up the virus from sick patients and bring back it back to their classrooms.

At U. of C., Bartlett said the hospital staff was working to give patients and families advanced warning of the new rules.

An announcement was made last week, and on Tuesday, patients received hand-delivered letters explaining the restrictions and “the rationale behind what is a very disruptive practice,” she said.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2017. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)