CHICAGO (CBS)– The CDC is issuing a Health Advisory for a mysterious illness seen in children.

Experts believe it may be linked to the coronavirus multi-system inflammatory syndrome and children account for at least three deaths reported in several states including, Illinois.

CBS 2 spoke with a local mother whose son became seriously ill.

“It hit so quick, it was like one minute he was fine and the next minute it’s like he woke up with this weird strange fever,” Sara Garcia said.

She said her son Nolan’s health quickly declined. Earlier this month, at one point, his fever almost reached 105 degrees,

When she couldn’t get the fever down, she took her 6-year-old to the ER at Advocate Lutheran General.

“I didn’t know what it was, but my doctor had told me the only real virus going around right now would be COVID,” Garcia said. “But, I was thinking, well none of us are sick, we didn’t go out, I’m not quite sure.”

Doctors told her Nolan’s coronary arteries were enlarged, a symptom often associated with Kawasaki disease. Hours later, Nolan tested positive for COVID-19, but often kids with the same symptoms are not testing positive.

“It wasn’t typical what you are thinking COVID symptoms,” Garcia said. “There wasn’t a cough, he was not having a hard time breathing.”

Nolan is one of more than 130 recorded cases of pediatric multi-system inflammatory syndrome in the U.S. Hospitals in 11 states and DC say they have treated patients.

“There is usually some mouth lesions, you can have swelling and rashes and then conjunctival infection with red to the white part of the eyes when there isn’t discharge or tearing,” Dr. Cynthia Ambler, a pediatrician at Northwestern Medicine, said.

She said parents should keep an eye out for any of those symptoms and call your doctor if your child has a prolonged high fever or any combination of the symptoms.

Now’s not the time for people to avoid the hospital. Kids can get sick quickly with this illness, so if you notice any of those symptoms, the hospital is your best resource to help them get better.