An outbreak of Clostridium perfringens has left over 100 students at the University of Canterbury’s University Hall in Christchurch, New Zealand, suffering from foodborne illness. The outbreak occurred during the end-of-year exam period, prompting an investigation by Health New Zealand and the Ministry for Primary Industries (MPI).
Laboratory tests and survey data revealed that the cause of the outbreak was likely linked to improperly prepared shredded chicken served as part of a meal. Clostridium perfringens and its toxin were detected in fecal samples from affected students, confirming the theory.
According to Vincent Arbuckle, deputy director-general of New Zealand Food Safety, the issue arose from unsafe practices around cooling, reheating, and hot holding of the meat. “The time between eating the food and the onset of symptoms, averaging about 11 hours, is typical for Clostridium perfringens infections,” said Arbuckle. He further explained that undercooked meat would have resulted in a different pathogen and a longer incubation period, such as two to five days.
An epidemiological analysis pointed to the shredded chicken dish as the key indicator of illness, with most students who consumed it falling sick. Fortunately, food safety officers conducted a thorough inspection of the kitchen and found no ongoing food safety risks, assuring students of their safety. However, the investigation into kitchen practices continues to prevent future incidents.
Arbuckle emphasized the need for safe food preparation, especially in large catering settings like university halls. “Cooling and reheating must be carefully managed to prevent the growth of harmful pathogens,” he stressed.
This incident is not isolated, as Clostridium perfringens outbreaks have been reported previously in New Zealand. In 2023, 27 cases were linked to the bacteria, with chicken and lamb dishes being common sources.
The university has taken steps to improve food safety measures, and students are encouraged to report any concerns to ensure their well-being.