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IDPH Reports Measles Case Identified in Cook County

News – Friday, October 13, 2023

First Measles Case in Illinois Since 2019 is a Reminder of the Importance of Measles Vaccine

CHICAGO – The Illinois Department of Public Health (IDPH) reports that on October 10, a suspected case of measles was reported by Cook County Department of Public Health (CCDPH) to IDPH.  The case, involving an unvaccinated individual with exposure internationally, was confirmed by the IDPH laboratory on October 11. IDPH is working with CCDPH to identify potential exposure locations in the U.S.  The case’s rash onset was identified as October 9; therefore, the infectious period would be between October 5 through October 13.  Prior to this case, the last measles case in Illinois was identified in 2019.

Most people are vaccinated routinely in childhood and are not at high risk.  Of most concern are people who have not been vaccinated.  Individuals who think they have been exposed should check with their health care provider about protection through prior vaccination or the need for vaccination.

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.

“This first reported case of measles in Illinois since 2019 is a reminder that this disease can be prevented with up-to-date vaccination,” said IDPH Director Dr. Sameer Vohra. “Two doses of measles vaccine are 97% effective in preventing measles. 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.”

"This is a good reminder to everyone to talk to their healthcare providers to make sure they and their loved ones are up to date on their vaccinations," said CCDPH Chief Operating Officer Dr. LaMar Hasbrouck. "According to the CDC, one dose of MMR vaccine is 93% effective against measles and two doses are 97% percent effective, if exposed."

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 when they come in contact with mucus or saliva from an infected person.

IDPH stresses the importance of ensuring everyone in your family is up to date on their immunizations. Since the COVID-19 pandemic, vaccination rates in the United States have dropped, increasing the likelihood of more cases of vaccine-preventable diseases. Individuals can protect themselves and their communities by doing their part and ensuring their families are up to date on vaccines.

For more information about measles, contact your health care provider, or visit the Illinois Department of Public Health webpage on measles  or the CDC’s measles site.