The State Department issued its highest-level travel advisory, Level 4, because of the Coronavirus outbreak on Thursday night.
After more than 7,700 cases and at least 170 deaths, the State Department is warning Americans not to travel to China, which has seen more than 90% of coronavirus cases.
"I feel like it's very scary, and everyone should protect themselves," said Nasir Shaw of South Philadelphia.
Some of those airline passengers are protecting themselves by wearing face masks as they travel.
Marta Pietruszka is one of those passengers
"I thought, you know, just for safety," she said while wearing a face mask in Philadelphia international Airport.
She'd just traveled from Orlando where she says many more people were wearing face masks in the airport.
"None of the masks were available. I had to get one at Home Depot. They were all sold out," Pietruszka said.
We checked area drug stores and found a shortage of masks, as well. Some shelves were empty while just one box of masks remained at another store.
One worker said that customers have been asking for them increasingly.
Tesha Cagle works in the medical profession, so she was well-equipped to get a mask before her trip.
"I have a spray that is hospital grade and masks," Cagle said while preparing to go through airport security. "I haven't put everything on in the airport. But I probably will when I get on the plane with all the recycled air."
Still, not every traveler is worried.
"I'm not really concerned," said Herman Beyleveld of Columbus, Ohio. "You don't see much of it happening here. The numbers are still low. What are the chances of getting it?"
Philadelphia International Airport doesn't have any direct flights to China. But passengers do go through other airports that do have flights that go to and from China.
They think it's worth it to take precautions.
"(Wearing a mask) makes me feel better," said Pietruszka.