State health officials say there has been a spike in mumps cases this year.
Evanston Township High School is a large high school, so one case of mumps could potentially be exposed a large group of people. The state says the number of mumps cases in Illinois is the highest it has been in at least the last five years.
Mumps can be spread through contact with each other and sharing various surfaces. That's part of the reason the director of Evanston's public health department says she sent out a warning that a person from Evanston high school contracted a suspected case of mumps.
"I wouldn't be too over alarmed at this point with one case, but I do appreciate the information so I can be on the lookout," said Laura Mudd, parent.
Most school-age kids have been vaccinated to prevent mumps, but doctors say the vaccination is not 100 percent effective. And some parents choose not to vaccinate their children. Some students learned about the suspected case of mumps during discussions in class.
Health officials Tuesday afternoon confirmed another case of mumps at Fremont Middle School in Mundelein.
Doctors say early symptoms include fever, headache, muscle aches, tiredness and loss of appetite, followed by swollen salivary glands. They suggest washing hands frequently, avoiding shared cups or utensils and sneezing or coughing into a tissue.
The case in Mundelein involves a 12-year-old boy who was able to return to school on Monday. School district officials there said it was an "isolated" incident.