Even while airports, like Philadelphia International, have precautions like mask wearing, health officials are still worried about a surge in cases.
"Just wear the mask. That's all you gotta do. That's the only thing that's different," said Will Glick, who was visiting family in Cape May.
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At the airport, TSA lines wrapped around corners as masked and gloved workers checked people into their flights. Some travelers chose to fly Monday to avoid the weekend crowds.
"Cheaper flights and to stay away from one of the busiest days yesterday," said James Cameron from Houston.
"This is my first time, actually was kind of nervous, but I think I'm going to be fine," said Milan Landers, who was flying to visit her husband in Florida.
Over the two week holiday travel period, more than 17.7 million people were screened at TSA checkpoints nationwide. That's more than six times the number of people AAA predicted would travel by air.
On Sunday alone, TSA screened more than 1.3 million people, the highest number since the pandemic began.
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"I think I'm around more people at Walmart, to be honest, than at the airport," said Cherie Gottshall from Auburn, Pennsylvania.
State rules require travelers to get a COVID-19 test within 72 hours or quarantine for 10 days.
Delaware County amped up staffing at its COVID testing site at the US Army Reserve in anticipation of a holiday surge, but lunchtime lines were thin. Volunteers say the testing crowd comes in waves.
"I think that's kind of the key is being prepared and looking at trends and knowing that after other holidays we had similar kind of response," said Karen May, a volunteer nurse there.
The airport has its own COVID-19 testing site too for passengers. It recommends people who want to take advantage of it to plan ahead and allow time for the test to be processed.