A passenger arriving on an international flight at Chicago’s O’Hare Airport last Wednesday may have exposed some people in the airport to measles, health officials say.

While they stress there is no current risk to the public, the Illinois Department of Public Health said in a statement that anyone inside O’Hare between 6:30 a.m. and 1 p.m. on January 10 may have been exposed to the measles virus.

On January 10, a passenger on an international flight with a contagious case of the measles arrived in O’Hare’s Terminal 5 and traveled through Terminal 1, possibly in addition to other areas of the airport, officials say.

The passenger was diagnosed with measles after arriving in his home state. Soon afterwards, the Centers for Disease Control learned of the case and contacted passengers who sat next to the passenger during his journey. Health agencies are now working to inform others who were inside O’Hare on January 10 that they may have been exposed.

“If you weren’t at O’Hare on January 10 there’s no concern, and even if you were the risk was very, very low, and even if you’ve been vaccinated it’s next to nothing,” said CDPH Chief Medial Officer Dr. Allison Arwady.

Since the vaccine that protects people from measles is a standard childhood vaccine, travelers who received it as a child are generally protected. But if you have not been vaccinated or you were traveling with small children that day you should check in with your doctor, officials say.

If you were exposed to measles, symptoms could come on as late as January 31, and include rash, high fever, cough, runny nose and red, watery eyes. If you think you have it, do not go to the doctor’s office right away; call first so you don’t infect anyone else.

The Chicago Department of Public Health says there is no current risk for travelers coming into or out of O’Hare and they do not expect an outbreak, but it’s a good reminder to make sure you and your children have all your vaccinations.