Manuel Balce Ceneta / AP, file
White-tailed deer similar to this one were the source of an odd outbreak of E. coli food poisoning among students in a Minnesota high school science class.
A Minnesota high school science project that involved hunting and butchering deer -- including one road-kill capture -- and turning the meat into venison kabobs backfired when 29 students were sickened with a rare kind of E. coli food poisoning, investigators say.
The 2010 incident just now reported in the journal Emerging Infectious Diseases highlights the risks of E. coli contamination, not just from factory-produced meat, but also from small, local providers.
Doctors first knew they had a problem in December 2010 when two kids from the same high school turned up at a Minnesota hospital with abdominal pain and bloody diarrhea. Fearing they had a food poisoning outbreak on their hands, they quickly called in the state’s top-notch public health officials.
Both teens had taken part in a school environmental science and outdoor recreation class that involving hunting, shooting and butchering six white-tailed deer, explained Joshua Rounds, the study’s lead author and an epidemiologist with the Minnesota Department of Public Health. A seventh deer was harvested after being hit by a car, the report says.
The deer were processed on school grounds and then grilled and eaten in class a few weeks before the students got sick.
Epidemiologists interviewed 117 kids in five class periods and found that 29 definitely had become ill, but not with E. coli O157:H7, the strain commonly associated with food poisoning from ground beef.
Rounds suspected the deer might have carried another E. coli strain that also produces poisons known as Shiga toxins. He was right. Samples from the students and the deer meet turned up E. coli O103:H2, which is part of a larger category of non-O157 Shiga toxin-producing E. coli bugs, known as STECs.
Scientists also turned up another E. coli strain, E. coli O145:NM that didn’t produce Shiga toxins.
STECs are becoming a more worrisome form of E. coli, so much so that federal agriculture officials are poised to begin banning six strains of the possibly lethal bacteria from some forms of beef in the nation’s food supply starting next spring.
Under the new regulations, the bacteria will be considered adulterants and it will be illegal to sell beef contaminated with the bacteria collectively dubbed “the big six,” including Shiga-toxin producing E. coli O103 and O145.
In the case of the Minnesota deer hunters, the source of the problem was clear.
People don’t usually get sick from eating hunks or steaks of muscle meat, Rounds said. In this case, however, the meat had been skewered and cooked only to medium rare. The skewers had dragged contaminants from the meat’s surface down to the center of the kabobs, which hadn’t been cooked to a high enough temperature to kill the bacteria.
Unless the entire hunk of meat is cooked to 165 degrees Fahrenheit, there’s a risk of food poisoning, Rounds said.
Another factor was hand-washing when handling meat -- or the lack of it, Rounds said.
Not everyone in the class was as fastidious about cleaning their hands as they could have been.
“If you think about high school males, they’re probably not the best when it comes to food safety practices,” he said. “So you can have cross-contamination.”
The case is a reminder, Rounds said, that all meat, no matter where it comes from, should be treated with careful precautions.