OWATONNA — Owatonna High School has made grief counselors available to students following the death of a senior who experienced flu-like symptoms.

Family members said 17-year-old Shannon Zwanziger was sick for a week. Her father, Terry Zwanziger, said her symptoms worsened, and her heart stopped Tuesday morning. She was flown to the Mayo Clinic in Rochester, where she was pronounced dead.

Tests results are pending to determine whether Shannon had influenza. Her father said the family was told that results may not be available for eight to 12 weeks.

Shannon was one of more than 100 OHS students absent between Thursday and Monday because of flu-like symptoms. Principal Mark Randall said those numbers are at least double from last year at this time, but they’re declining.