A spike in measles cases in the Chicago area has public health officials on watch across Illinois.
Illinois has seen 66 cases this year through April 22. That’s more than half of the 125 cases around the country. The U.S. saw only 58 measles cases nationwide in 2023.
This is the most cases the country has seen since an outbreak of nearly 1,300 cases across 31 states in 2019. Illinois only had nine cases that year.
Measles is a highly contagious virus that affects mostly, but not exclusively, children. It can cause high fever, sore throat, and the red rash the disease is famous for. The rash starts on the face and eventually covers the whole body.
“If you have 10 people in a room that are not immune to the measles, and one person with it walks in, nine of those people will get measles,” said Heidi German, communicable disease coordinator for the McLean County Health Department.
In rare cases, the virus can cause serious respiratory infections or encephalitis, swelling in the brain that could lead to permanent brain injury and may not happen for months after having the virus. Measles is also known to cause complications with pregnancy, including premature birth and fetal death.
Measles is spread through the air from contaminated particles from the coughing or sneezing of an infected person. The virus can survive in the air for up to two hours after leaving its host body, German noted.
The disease was endemic in the U.S. until 2000, when the nation finally achieved elimination status.
The U.S. is in danger of losing its eliminated status as cases spike around the country. This is happening at the same time as a drop in vaccination rates. Coverage rates in schools fell from over 95% to just over 93% between the 2019-20 and the 2022-23 school years.
German doesn’t believe there is much risk in McLean County.
“We were getting things from the (Illinois Department of Public Health) on a regular basis and those have majorly slowed down,” she said on WGLT's Sound Ideas. “I’m thinking hopefully that this outbreak has kind of just stopped."
German said the only way to truly protect yourself from measles is to get vaccinated.
“Most people have never gotten the measles,” she said. “It [the vaccine] is very, very effective.”
The measles, mumps, and rubella vaccine, also known as MMR, was introduced in 1971. A stand-alone measles shot has existed since 1963. The vaccine needs two doses, both usually given in early childhood. The first shot is given between 12 and 15 months and the second between the ages of 4 and 6. The vaccine can be given at any age, though.
“It just immunizes your body and helps your body to fight it off,” German said. “So measles is still around, but when you have the immunization, you either have no symptoms or symptoms that are so small that people don’t even know.”
German recommends anyone who hasn’t been vaccinated to get the shot, especially those traveling to countries that have not reached elimination status, or people planning to become pregnant.
You can check your vaccination status through the Illinois Department of Public Health's Vax Verify feature. Most states have a similar system for checking your status.
