Digesting the Data: Overview of Foodborne Outbreaks in Canada Submitted to Outbreak Summaries, 2008–2023

Outbreak Summaries is a Canadian enteric, food, and waterborne outbreak surveillance system designed to support the collection and analysis of Canadian outbreak data. This analysis summarizes the foodborne outbreak investigations submitted between 2008 and 2023. Finalized reports of foodborne outbreak investigations submitted by all participating jurisdictions were extracted and characterized by pathogen, outcomes, food vehicles, and pathogen-food vehicle pairs. Annual trends in submissions and jurisdictional scope were explored. A total of 452 foodborne outbreaks were submitted by 11 participating provinces and territories alongside the Public Health Agency of Canada included in the analysis. A total of 14,650 illnesses, 1268 hospitalizations, and 68 deaths were reported. Almost 70% of all submitted outbreaks were caused by bacteria, and viruses accounted for 20%. Salmonella was the most common cause of outbreaks (184/434, 42% of outbreaks with a known pathogen) and outbreak-associated illnesses (7003/14,418, 48%), followed by Norovirus outbreaks (72/434, 16%) and outbreak-associated illnesses (2599/14,418, 18%). The highest absolute number of hospitalizations was attributed to Salmonella ( n = 796), followed by Escherichia coli ( n = 249), and Listeria monocytogenes ( n = 97). L. monocytogenes had the highest hospitalization rate (94%, n = 97), and case fatality rate (17%, n = 35). A confirmed or suspected food vehicle was identified in 230 outbreaks (51%), accounting for 10,587 outbreak-associated cases (72%). The most frequently identified food vehicles were raw vegetables ( n = 36, 15.7%), chicken ( n = 29, 12.6%), and fresh shellfish ( n = 17, 7.4%). The pathogen-food pairs associated with the most outbreaks were Salmonella in chicken (26/221) and whole eggs (15/221) and E. coli in raw vegetables (13/221). Analysis of foodborne outbreaks in the context of pathogens and food vehicles supports the investigative work of public health authorities in Canada. The expansion of program participants and more than 15 years of surveillance data provide a more comprehensive understanding of the foodborne outbreak landscape in Canada.