The number of measles cases in Illinois climbed to 14 Tuesday, public health officials said.
The most recent case is another infant from a Palatine day care at the center of a northwest suburban outbreak, according to the Illinois Department of Public Health.
All 14 cases reported statewide are in Cook County and 13 of them are related to the outbreak at the KinderCare Learning Center, including one adult and 12 infants.
One of the infants diagnosed is from Chicago while the adult was a student at Elgin Community College, officials have said.
A second adult diagnosed earlier this year was not related to the day care outbreak.
Illinois health officials are still trying to figure out how the people became infected with the measles virus. No ties have been found to the December outbreak at Disneyland in California, health officials said.
None of the people infected so far in Illinois had been vaccinated for measles, health officials said.
Measles is a highly contagious respiratory disease that can cause severe health complications, including pneumonia, encephalitis and death.
The DuPage County health department warned of possible exposure at three locations, but the state health department has not confirmed any cases.
