Dr. Keith Warriner, a food scientist in the Ontario Agricultural College, spoke to several news outlets this week following a large E. coli outbreak at several Calgary daycares, and the deaths of several people in the U.S. due to contaminated oysters.

Warriner spoke CTVNews.ca and helped explain the most common and most serious causes of foodborne illness, and why statistics on these illnesses are so unreliable.

In an interview with Yahoo! News Canada , Warriner discussed the outbreak of deadly illnesses in the U.S. linked to raw oysters. 

Warriner said oysters can easily be contaminated with noroviruses or Vibrio, a genus of naturally occurring bacteria. He added that oysters “are considered one of the most high-risk foods per serving.” 

A professor in the Department of Food Science, Warriner researches food safety and microbiology with an emphasis on food-borne viruses like listeria.