Enteric disease: A major health concern in Canada

Despite efforts to reduce the presence of dangerous pathogens in Canadian food and water, Salmonella, E. coli, Campylobacter, Yersinia, Listeria, Shigella, Vibrio, Cryptosporidium, Cyclospora, Giardia, Norovirus, Rotavirus, and others continue to cause gastrointestinal, or enteric, disease in Canada. The Public Health Agency of Canada estimates that each year roughly one in eight Canadians (or four million people) get sick with a domestically acquired food-borne illness¹.

Most cases of enteric disease are mild and require only a day or two of reduced activities. However, these cases pose a significant burden due to lost productivity and other related costs. Other cases are severe and can result in hospitalization, serious chronic conditions or death.

Traditional passive surveillance systems, which rely on a patient to seek care from their doctor and submit a stool sample, have resulted in the under-diagnosis and under-reporting of enteric disease in Canada (and internationally).

• According to the Public Health Agency of Canada's 2013 Estimates of Food-borne Illness in Canada¹ (which developed estimates of under-reporting and under-diagnosis for several pathogens causing food-borne illness):
  • For each case of verotoxigenic E. coli O157 reported to Canada's national surveillance system it is estimated that there are approximately 20 cases in the community.
  • It is estimated that there are approximately 26 cases of Salmonella and 27 cases of Campylobacter in the community for each reported case.¹
• Only about 14 percent of people with mild symptoms and 44 percent of people with more severe symptoms of E. coli O157, Salmonella or Campylobacter infections seek medical care.¹

FoodNet Canada (formerly known as C-EnterNet) was launched to help answer the question of the true burden of enteric disease in Canadian communities and help to improve food and water safety in Canada. Data from FoodNet Canada's first sentinel site was integral to the development of the most recent estimates of food-borne illness in Canada.

FoodNet Canada's comprehensive and integrated surveillance system focuses on active surveillance of human cases of illness, coupled with monitoring possible sources of illness in food, animals, and water. The information gathered helps us to better understand long-term trends of enteric disease and develop Canadian-specific source attribution estimates. FoodNet Canada also helps to answer important questions about source attribution; for example, how much salmonellosis in Canada is caused by certain food types versus others. These objectives are being addressed not only in Canada and the United States, but at the international level as governments strive to improve the safety of our food and water supplies.

¹ M. Kate Thomas, Regan Murray, Logan Flockhart, Katarina Pintar, Frank Pollari, Aamir Fazil, Andrea Nesbitt, and Barbara Marshall. Foodborne Pathogens and Disease. July 2013, 10(7): 639-648. doi:10.1089/fpd.2012.1389.