MARION, Ill. (WLS) — The Chicago Department of Public Health and Cook County Department of Public Health have identified the first two cases of measles in Cook County this year, the agencies said Wednesday evening.
One case is an adult, who is asuburban Cook County resident, and whose vaccination status is unknown, health officials said.
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They went to a local hospital on Monday, officials said.
The other case is an adult Chicago resident, who traveled internationally through O’Hare airport in early April, officials said.
That person had one prior dose of MMR vaccine. The person had a rash onset on Friday, and has been isolated at home since being diagnosed.
The following locations are points of potential public exposure:
– April 21: Chicago Public Library – Independence Branch, 4024 N. Elston Ave.
– April 21: Fittingly Delicious, 3939 W. Irving Park Road
April 22: O’Hare airport, between 10 a.m. and 8 p.m., especially Terminal 1
– April 23: O’Hare airport, between 10 a.m. and 8 p.m., especially Terminal 1
– Friday: Aldi. 7235 39th St., Lyons, between 10 a.m.-12:30 p.m.
– Sunday: Shell. 3901 S. Harlem Ave., Stickney, between 10 a.m.-12:30 p.m.
– Monday: Mobil, 2945 S. Harlem Ave, Berwyn, between 10:20 a.m.-1 p.m.
Those who may have been exposed should tell healthcare providers, if they are unsure about their vaccination status. The healthcare provider will determine the need for testing if symptoms develop.
If an exposed person develops symptoms, her or she should notify his or her healthcare provider or a healthcare facility before going to a medical office or emergency department for evaluation to ensure that special arrangements can be made to prevent other patients and medical staff from possible exposure.
“Most individuals are vaccinated against measles routinely in childhood and are not at high risk. The best defense against measles is vaccination. Two doses of MMR vaccine are 97% effective against measles and generally provide lifelong immunity,” health officials said.
The Illinois Department of Public Health reported the first case of measles in the state in 2025 last week.
That patient is an adult in far southern Illinois.
An outbreak in Chicago early last year led to 67 cases.
Earlier this month, Indiana health officials announced at least six cases in Allen County, which is in the area around Fort Wayne.
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Measles is highly contagious, and is spread when an infected person sneezes or coughs.
Illinois officials said the risk of measles transmission for the general public in Illinois remains low.
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