CHICAGO (WLS) -- Some travelers at O'Hare Internation Airport said they had no issues flying during a pandemic, on what is traditionally one of the busiest days of the year at airports.
"I felt completely safe," said Alicia Gerin.
"The planes were full. Everybody was respectful. Everybody had their mask on," added another traveler.
Public health officials fear coronavirus cases will soar over the coming weeks after travel and home gatherings for Thanksgiving.
Dr. Anthony Fauci is among many doctors urging people to not let their guard down.
"We may see a surge upon surge. You know, we don't want to frighten people, but that's just the reality," he said. "We said that these things would happen as we got into the cold weather and as we began traveling."
COVID-19 testing sites are preparing to be flooded with people this week, similar to to the days leading up to Thanksgiving, just as Chicago-area hospitals brace for a post-Thanksgiving COVID-19 spike after the long holiday weekend,
"We are concerned that there will be a ramp-up in cases," said Dr. Bala Hota at Rush University Medical Center. "The incubation period to develop symptoms is about five to seven days, so it would be mid-next week where people might have some symptoms of the illness, and that would be when we would expect more cases to come into the hospital."
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"We definitely feel like there's going to be a big spike because of the gatherings. We're very fearful that there will be a spike in positivity rates, and spreading throughout our community, unfortunately," added Innovative Express Care CEO Dr. Rahul Khare.
Health officials said Thanksgiving travel numbers are a clue that the positivity rate could start climbing, yet again.
AAA predicted more than 50 million people had plans to travel for the holiday. Chicago's O'Hare International Airport is just one that had a steady stream of travelers as well.
"If there is going to be a spike, it will be sometime late next week through about 2-3 weeks after that," Dr. Hota said. "Even though it is steady about 7-10 days we are going to see a real ramp up in admissions. We are prepared for that."
That is why Dr. Khare recommends waiting at least a few days before getting tested.
"Three to five days is really important if you did, go and see people, and we're unmasked, we know that this happens. And if that's what happened. Please get tested three to five days after you had your encounter," Dr. Khare said.
Right now, the statewide positivity rate in Illinois remains just above 12%, but with fewer people getting COVID-19 tests over the holiday weekend, the data could be misleading.
"Even though it has been somewhat stable, that translates to quite a bit of disease, and it also shows that there is pretty significant spread in the community," he added.
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Just in the past three weeks, the coronavirus hospitalizations at Rush have tripled.
"What we are seeing now is anywhere from 10-25 admissions per day," Hota said.
Many of those patients are now in the ICU.
Still, doctors are asking people to practice social distancing and monitor their symptoms to avoid another surge.
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"(In) December, we could see a decline in cases but it is dependent on what we do -- If we wear masks, wash hands and distance," Hota pointed out.
If you did go to a gathering, monitor for symptoms and limit contact with others until you have a COVID-19 test result.