Medical professionals at OSF St Francis Medical Center say we're about four weeks into the real center of flu season and according to data from the CDC, it's shaping up to be one of the worst in decades.
The emergency room at OSF is on high alert with the fast moving flu season. Nursing Director of Emergency Services, Debbie Trau, said their number of patients keeps going up.
"So the flu trends according to the CDC and Public Health Department are tracking probably some of the worst flu we've seen in up to 40 years." said Trau, "The flu we're seeing is respiratory, not gastrointestinal like a lot of people call the flu, it is a respiratory ailment and it impacts the immune system as well."
Medical Director for the Emergency Department, Victor Chan, said flu symptoms come on very quickly.
"Fever, body aches, and cough. Those are the tell tale signs of influenza. If you are having the nausea, vomiting and diarrhea those are maybe more of what we call a GI flu or a stomach bug flu." said Chan
The most at risk are children under two, the elderly, pregnant women and those with pre-existing conditions.
"There's a medication that's an anti-viral medication that you can start within two days, after two days it's not much help so it's really important that you seek help within the first two days of the onset of symptoms." said Chan
One of the best defenses is the flu shot which takes two weeks to process in your body.
"You may feel the body aches, it's your body's response, your immune system ramping up to prepare to fight off the flu so that you can build those antibodies to fight off the flu." said Chan
OSF's priority is to keep their patients safe so if you think you may be sick, it's best not to visit others in the hospital.
"Some of our patients who are already sick, getting a virus can really make them that much more ill and be life threatening to them." said Trau
In Illinois, the Department of Health reports nearly 200 Intensive Care Unit admissions due to the flu since September, 56 of those in the past few weeks alone.
The CDC reports 9.7 millions cases across the U.S.