CHICAGO (WLS) -- Memorial Day weekend brought out large, non-social distancing crowds all over the country - almost as if the coronavirus pandemic doesn't exist.
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From Alabama to Missouri to our neighboring states of Wisconsin and Indiana, pools, beaches and bars opened up with a vengeance.
"We are going to see another surge and we're going to see that surge sooner than later if people do not maintain the appropriate public health guidance," said Dr. Rachel Rubin, Cook County Health Dept.
Guidance like wearing masks and social distancing appeared to be ignored in Lake Geneva over weekend, where many Illinois residents spent their holiday.
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"The more we think it's OK for us to go to other cities and states, the more people from other states think it's going to be good to come to us," said Dr. Emily Landon, University of Chicago Medicine. "It's just more moving the virus around the country."
Infectious disease specialist Dr. Emily Landon urges people to use caution when considering summer vacations in other states or a staycation. If a beach is too crowded, Landon says to turn around and go home.
"Nothing has changed about the virus in the time that we've been spending at home," Dr. Landon said. "What is supposed to change is us, we are supposed to figure out how to exist with the virus."
Mayor Lori Lightfoot said the lakefront will eventually open in Chicago later this summer, but she warns if crowds get too big, she'll shut the beaches down
Which is why the mayor makes no apologies for reopening Chicago in a slow and measured way.
"We are not going to undo all the hard work, all the sacrifice that people have little paid for with lives," Lightfoot said.
While the numbers have gone down, the pandemic is still here and doctors say all it takes is one carrier in a big crowd to become a super spreader.
Coronavirus US: Doctor warns of 'another surge' after crowds ignore social distancing, mask guidelines over Memorial Day
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