SPRINGFIELD — There is still no definitive answer for what caused 30 students in Springfield to become ill last week, but "diagnosis by exclusion" has resulted in the Minnesota Department of Health pointing to psychogenic illness, said spokesman Doug Schultz.
A battery of air-quality tests by numerous agencies, as well as tests conducted on the patients at Mayo Clinic Health System in Springfield, have not turned up any irregularities. Carbon monoxide exposure, which originally was suspected, was ruled out.
"You're basically left with a mass psychogenic illness," Schultz said. "(But) it's nothing you can prove."
Psychogenic illness means the sickness of one or more people leads other people to then also feel sick.
At about 9 a.m. Feb. 6 students were practicing for choir when 10 or more suddenly became ill. They were taken to the nurse's office and because of the large number of them, the school initiated its emergency response plan and evacuated the school, which included all 600 students who were taken to the community center.
Eleven children were initially taken to Mayo Clinic Healthy System in Springfield with symptoms commonly associated with carbon monoxide exposure, such as headache and nausea. By day's end, 30 children had been seen at the hospital and all had been discharged.
The Springfield Fire Department, Centerpoint Energy and the Institute for Environmental Assessment conducted numerous tests at the school and repeated them Friday. No gas leak or air-quality issues were found.