CHICAGO (CBS) — Another case of measles exposure has been reported at O’Hare International Airport, the second instance there in five days.

This case involves a patient who was at the International Terminal on Jan. 9. The State Department of Public Health insists there is no outbreak.

“There have been two, unconnected and unrelated individuals who traveled through O’Hare Airport, one on January 9th and one on January 10th,” said Nirav D. Shah, Director of the Illinois Department of Public Health. “Both of them had measles.”

But, people at the airport between 8:30 a.m. and noon could be at risk of infection.

The Illinois Department of Public Health said the patient already was infected with the measles upon arrival at the airport.

The other case was reported on Jan. 14. That patient arrived at the International Terminal and then boarded a domestic flight at Terminal 1.

In the most recent case, the patient was also at the Concourse Office Plaza, 4709 Golf Road in Skokie on Jan. 10. The patient then went to three health care facilities between late evening of Jan. 10 through the early morning of Jan. 13–first Northshore Evanston Hospital, then Northshore Skokie Hospital and Advocate Lutheran Hospital in Park Ridge.

“One of the reasons that we’re taking the steps to notify the public is that the measles virus is highly contagious. The virus can linger for up to two hours in the air or on surfaces,” Shah said.

The timeline for exposure at the office plaza would be 11 a.m. to 2 p.m.; 11 p.m. to 1:20 a.m. (Jan. 10-11) at Evanston; 11:50 p.m.-3:30 a.m. at Skokie (Jan, 10-11) and Park Ridge 3:15 p.m.-2:15 a.m. (Jan. 11-13). The times represent the window of potential exposure to others, not the actual time the patient was in those place.

The reason for the multiple visits to those facilities was not immediately known.

People who are considered to be close contacts and most at risk, including passengers on the inbound flight to O’Hare and others in the airport, are being contacted directly by local health departments.

Symptoms include rash, fever, cough, runny nose, and red, watery eyes. If infected, individuals could develop symptoms as late as February 1, 2018. Shah said most people have been vaccinated, but those who haven’t are most at risk.

“It is important for everyone who can be vaccinated to get vaccinated, if they aren’t already,” said IDPH Chief Medical Officer Dr. Jennifer Layden. “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. Two doses of measles vaccine are about 97 percent effective in preventing measles.”

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