The Virginia Department of Health is warning people who flew through D.C.-area airports the first week of January about a potential measles exposure following a confirmed case in one individual who was traveling through Northern Virginia.

You may have been exposed to measles if you were in the international arrivals area of the main terminal at Dulles International Airport on Wednesday, Jan. 3 between 4 p.m. and 8 p.m., health officials say. The same goes for passengers or others who were in Terminal A at Ronald Reagan Washington National Airport on Thursday, Jan. 4 between 2:30 p.m. and 6:30 p.m.

Measles is highly contagious and can spread through the air when an infected person breathes, coughs, or sneezes.

The Department of Health is warning travelers who have never received a vaccine or are otherwise at risk to watch out for signs of measles until Jan. 25. Symptoms include a high fever, runny nose, watery eyes, and a cough, and usually begin seven to 14 days after exposure. About three to five days after symptoms begin, a rash develops on the face and spreads to the rest of the body.

Health officials are asking anyone with symptoms of measles to isolate themselves and to contact their health care provider or an emergency room right away.

In Virginia, approximately 95% of kindergartners are fully vaccinated against measles but infants younger than 12 months cannot receive the vaccine and are at risk of infection. Immunization records in Virginia can be requested online or by contacting your health care provider.

Individuals who have received two doses of a measles, mumps, and rubella (MMR) vaccine are protected and do not need to take action, officials said.