CHICAGO (CBS) — So how will flu season look during a pandemic?

Doctors and health care workers have been asking that very question lately. CBS 2’s Marissa Parra spoke on Sunday with someone on the front lines of an intensive care unit to get some answers.

The 2020 winter flu season is filled with a lot of unknowns, especially with concerns over a possible “twindemic.”

“There’s a lot of anxiety around that,” said Dr. Benjamin Seides, an interventional pulmonology doctor at Northwestern Memorial Hospital. “This period of time, we tend to see an increase of hospitalizations due to influenza, and how that’s going to confound our current crisis.”

Seides works with Northwestern’s ICU and said amid a surge of COVID-19 cases in Illinois, they are seeing another rise in COVID-19 patients and ventilator use.

The good news is they are more ready for it now than they were back in the spring. But back in the spring, they only really had to worry about COVID-19.

And if someone is feeling that malaise and those symptoms and they’re worried whether they have the flu or COVID-19, is there an easy way to tell the difference?

“So no, not really,” Seides said.

He said that is one of the most vexing things about it all – that the two illnesses often present in similar ways.

But the other fear is coinfection – amid reports that a handful of people in other states have tested positive for both influenza and COVID-19.

Parra asked Dr. Seides whether these patients are battling both illnesses at the same time, or battling one and testing positive for both.

“It’s unlikely they’d be battling one and testing positive for both,” Seides said. “I don’t think we know enough to know how those two illnesses as a coinfection will look clinically.”

And while we don’t know for sure yet, it’s possible that having both at the same time could be worse than having one at a time. So aside from the usual advice of social distancing and wearing a mask, the ICU doctor had one more plea.

“We have an influenza vaccine, so go and get it,” he said. “It’s doubly important this year, because we are struggling with resource management.”

Dr. Seides’ other piece of advice is to treat your illness like it is COVID-19 by isolating yourself from others until you can get tested.