Carbon monoxide poisoning is the suspected cause of the illness that sent 30 children from the public school in Springfield, Minnesota, to the hospital Thursday. The building was evacuated after students became ill, and school was canceled Friday as officials continue to investigate.
The New Ulm Journal, citing fire department sources, reported that no carbon monoxide had been found by emergency personnel who checked the K-12 school building during the day Thursday.
But the Mankato Free Press reports lab tests indicated some patients had higher than normal levels of carbon monoxide in their blood. Micah Dorfner, a spokesman for the Mayo Health System in Mankato, told the newspaper by Thursday night all of the students had been discharged.
Hospital administrator Scott Thoreson said the elementary-age patients had symptoms that included headaches and nausea, common symptoms of carbon monoxide poisoning. Hospital staff treated the patients with oxygen, the newspaper reports.
According to KEYC, Springfield School District Superintendent Keith Kottke evacuated all 600 students from the elementary and high school after students in fourth and fifth grade reported fainting and vomiting in the school's auditorium Thursday morning.
They were taken to the community center for evaluation before being released to their parents, according to KEYC.
The Free Press reports Thoreson said the hospital received an alert from the ambulance service that the hospital would see an influx of patients from the school.
The New Ulm Journal reports the ambulance initially took three students to the hospital for possible exposure to carbon monoxide. The Journal says while at the community center, ambulance personnel assessed other students, telling several they should consult with their physicians.
Many of the students heeded the advice as the number of hospitalized students grew from 11 initially to 30 by late Thursday afternoon. All of them had been released by Thursday night.
KARE 11 reports that school officials say the school will be closed on Friday as the investigation into the incident continues.
Carbon monoxide is a colorless, odorless gas commonly found in combustion fumes (more info from the CDC here).