According to the New Jersey Department of Health, an international traveler—who was confirmed to have the disease—arrived at Terminal B on a flight from Brussels. The flyer, who was highly contagious, may have also traveled to other sections of Newark Airport between the times of 12 p.m. and 4 p.m.

Officials have informed individuals that it could take until January 14 to develop symptoms of measles, which include a rash, high fever, and runny nose. In rare cases, the disease can be life threatening and unvaccinated individuals are at the most risk for infection.

The disease is easily spread through the air when someone coughs or sneezes, and people can also get sick if they come in contact with mucus or saliva from an infected person, reported CBS News.

It is strongly suggested that those who believe they have been exposed to call their doctor before going in or visiting an emergency room to prevent more spreading.

New Jersey’s Ocean County already has an ongoing outbreak of measles that has affected 33 people, but is unrelated to the airport’s exposure, according to New Jersey Health Commissioner Dr. Shereef Elnahal.

Dr. Christina Tan, New Jersey’s state epidemiologist is urging all residents to stay up to date with vaccine and immunizations.

“Getting vaccinated not only protects you, it protects others around you who are too young to get the vaccine or can’t receive it for medical reasons,” Tan said in a statement. “If you’re planning an international trip, the World Health Organization recommends that adults or adolescents unsure of their immune status get a dose of measles vaccine before traveling.”