A Kane County Health Department investigation showed that the majority of student absences at St. Charles East High School two weeks ago could not be attributed to the flu.
St. Charles Community Unit School District 303 closed St. Charles East on Oct. 21, 22 and 23 after 972 students, or 45 percent of the school, were absent Oct. 20.
About 8 percent of students reporting illness Oct. 19 and Oct. 20 complained of influenza-like symptoms, a health department report said. Influenza-like illness is defined as a fever with cough and/or a sore throat.
Around 22 percent of students were home with gastrointestinal illness, 20 percent with respiratory illness and the other 50 percent with variety of unrelated symptoms.
The report concluded that the increased absenteeism at St. Charles East did not appear to be due to a swine flu outbreak, but rather a combination of other several causes.