CHICAGO - The Chicago Department of Public Health (CDPH) has confirmed a case of measles in a Chicago resident, the first case identified in a Chicagoan since 2019. The source of the infection is unknown at this time and the infectious period ended on March 6. The individual is recovering well at home.

Although case investigation identified no recent travel outside of Chicago, the resident reported interaction with domestic and international travelers. No link has been identified between this case and a measles case in an Indiana resident who had visited Chicago last month. That case did not result in any secondary measles cases among Chicago residents.

Illinois had five measles cases in 2023. Those cases were the first in the state since 2019, when the last measles case was identified in Chicago.

CDPH is working to identify and notify people that may have been exposed to measles, including at the facilities where the Chicago resident sought medical care, and is in close contact with the Illinois Department of Public Health (IDPH) and the Centers for Disease Control and Prevention as the investigation continues.

CDPH and partners have identified the following exposure locations in public settings for which a list of exposed people cannot be obtained.

Members of the public who were at the location(s) on 2/27/24 below might have been exposed to measles:

• Swedish Hospital, Galter Medical Pavilion at 5140 N California Ave, Chicago, IL 60625 between 8:30am and 12pm.
• CTA Bus #92 (Foster) between 9:15 and 11:30am.

Anyone at the locations above on 2/27/24 during times listed should immediately call CDPH at 312-743-7216 Mon-Fri between 8am-5pm. CDPH will recommend next steps based on documented immunity to measles and level of exposure. Symptoms of measles include rash, high fever, cough, runny nose and red, watery eyes. After exposure to someone with measles, symptoms can take from seven to 21 days to show up. Individuals who develop symptoms of measles should contact a health care provider by phone or email BEFORE going to a medical office or emergency department. Special arrangements can be made for your evaluation while also protecting other patients and medical staff from possible infection.

While cases of measles are exceedingly rare in Chicago due to high vaccination coverage from childhood, reports of measles cases have been increasing recently internationally and in the United States. The measles-mumps-rubella vaccine (MMR) is extremely effective at preventing measles and remains by far the best protection against measles for people of all ages. However, measles is highly contagious and can be dangerous to those who are unvaccinated, especially babies and young children.

"The key to preventing measles is vaccination. If you are not vaccinated, we strongly encourage you to get the vaccine," said CDPH Commissioner Olusimbo Ige, MD, MPH. "If you are unsure whether you’ve been vaccinated, ask your healthcare provider to find out if you need an MMR. If your child is 1 year old or older, and has never received the MMR vaccine, contact your child's pediatrician to discuss how your child can get caught up with their vaccines."

Measles is a serious respiratory infection that causes a rash and high fever and is capable of leading to pneumonia and other complications. A first dose of MMR is recommended at 12 months of age and a second at 4 to 6 years of age, but it is never too late to get your MMR vaccine if you haven't already. CDPH offers MMR vaccinations at no cost for uninsured adults and children eligible for the Vaccines For Children program at our various health clinics around Chicago. Adults who aren't sure if they're vaccinated against measles should contact their health care provider. For more information about measles and how you can protect yourself, visit the CDC website.

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