COOK COUNTY, Ill. — The Illinois Department of Public Health said Friday that a positive test for measles was identified in Cook County.

The confirmation is the first case of measles in Illinois since 2019.

According to IDPH, on Tuesday, Oct. 10, the Cook County Department of Public Health reported a suspected case of measles to IDPH. The case involved an unvaccinated individual with exposure internationally. The IDPH laboratory confirmed the diagnosis on Wednesday, Oct. 11.

Health officials believe the infectious period would have been between Oct. 5-13. Symptoms include rash, high fever, cough, runny nose and red, watery eyes. Symptoms can take seven to 21 days to appear.

IDPH Director Dr. Sameer Vohra said Illinois’ first case of measles in four years is a reminder that the disease could be prevented with up-to-date vaccination.

“Two doses of measles vaccine are 97% effective in preventing measles,” Vohra said. “However, as we saw this week, it still can affect those who are unvaccinated. I urge everyone to make sure they and their family members are up-to-date on measles/mumps/rubella (MMR) vaccine and all other age-appropriate immunizations.”

Most people are vaccinated routinely during childhood and are not at high risk of infection. Locals who feel they have been exposed, however, should immediately contact their health provider by phone or email before an in-person visit at a medical care facility.

Health officials also cautioned Illinoisians that:

• Measles can cause serious complications such as pneumonia and encephalitis (swelling of the brain).
• Measles is easily spread through the air when someone coughs or sneezes.
• People can also get sick with measles when they come in contact with mucus or saliva from an infected person.

More information on measles is available on the Illinois Department of Public Health and the CDC‘s website.