The Chicago Department of Public Health is advising city residents to check their measles vaccination records, as the illness continues to spread in other parts of the country.
No cases of measles have been reported in Illinois this year. But across the country, there have been more than 300 cases so far this year in 15 states, according to the U.S. Centers for Disease Control and Prevention.
The measles, mumps, and rubella (MMR) vaccine is the most effective way to protect against catching the illness. Two doses of the vaccine are recommended for lifetime protection and are 97% effective against measles, according to the CDC. One dose is 93% effective against the illness.
Without protection, measles is highly contagious. If one person has the measles, up to 90% of the people nearby will catch it if they are not immune, according to the Chicago Department of Public Health.
People can check their vaccination status by contacting their health care providers or looking at their medical records. Or they can use the Illinois Department of Public Health’s online portal, Vax Verify, to check their immunization status.
The first dose of the vaccine, or a similar vaccine — the measles, mumps, rubella, and varicella (chickenpox) vaccine — typically is given at age 12 months to 15 months. The second dose is often given from ages 4 to 6.
The Chicago Department of Public Health offers MMR vaccinations for anyone who needs them, regardless of whether they have health insurance, at immunization clinics throughout city, a list of which can be found by going to getvaxchi.chicago.gov. The clinics take walk-ins, but patients are encouraged to register online or by calling the clinic.
Measles symptoms typically start about one to two weeks after a person is exposed to the illness and can include a high fever, cough, runny nose, red, watery eyes and a rash that breaks out three to five days after symptoms start, according to the CDC.
The recommendation from the Chicago health department comes amid outbreaks of the illness, including in Texas, which has had 279 cases since late January, according to the Texas Department of State Health Services. Of those cases, 277 people were either unvaccinated or their vaccination status was unknown.
In the Texas outbreak, 36 patients have been hospitalized, and one child has died. The child who died was unvaccinated and had no known underlying conditions, according to the Texas Department of State Health Services. The child was the first person to die of measles in the U.S. in a decade.
New Mexico has had the next-highest number of measles cases so far, with 38, according to the New Mexico Department of Health.
Illinois had an outbreak of measles in March 2024 in which 67 cases were reported, with most linked to a Chicago shelter for migrants on the Lower West Side where nearly 2,500 people were living in close quarters. It was the largest outbreak in Illinois since 1990, according to the state health department.
In Illinois, about 91.6% of kindergartners had received the MMR vaccine during the 2023-2024 school year. In Illinois, routine childhood vaccinations against diseases such as measles, polio and whooping cough decreased during the COVID-19 pandemic. Nationwide, the percentage of U.S. kindergartners vaccinated against measles decreased from 95.2% during the 2019–2020 school year to 92.7% in the 2023–2024 school year, according to the CDC.
