Three "probable" cases of whooping cough have been reported at schools in Huntley Unit District 158, district officials said this week.
Two cases are at Marlowe Middle School and one is at Huntley High School, according to an announcement on the district's website.
Officials said there are "several" other cases at Marlowe that have been referred to the McHenry County Health Department for follow-up.
They say it's part of an increased number of whooping cough cases in the Chicago area.
Whooping cough, also known as pertussis, is a highly contagious respiratory disease known for uncontrollable, violent coughing, according to the Centers for Disease Control and Prevention. It's transmitted through coughing and sneezing.
Infants and young children are most commonly affected by the disease since they have not been fully immunized against it, experts say.
District 158 officials said symptoms may include a persistent cough for two or more weeks, coughing fits where the person feels they cannot stop, and coughing until vomiting.
For more information, district officials recommend calling the health department at 815-334-4500.