Foodborne Botulism, Canada, 2006-2021¹

Area of Science:

• Foodborne illness epidemiology
• Public health surveillance
• Infectious disease outbreaks

Background:

• Foodborne botulism poses a significant public health risk, characterized by severe neuroparalytic illness.
• Surveillance data is crucial for understanding disease trends and informing prevention strategies.

Purpose of the Study:

• To analyze the epidemiology of laboratory-confirmed foodborne botulism outbreaks in Canada between 2006 and 2021.
• To identify trends in incidence, causative agents, and patient outcomes, with a focus on changes in Indigenous communities.

Main Methods:

• Retrospective analysis of laboratory-confirmed foodborne botulism outbreaks reported in Canada from 2006 to 2021.
• Data collection on case numbers, geographic distribution, botulinum neurotoxin serotypes, implicated food products, and patient demographics.
• Review of clinical data including hospitalization, intensive care unit admission, mechanical ventilation, and mortality.

Main Results:

• A total of 55 outbreaks and 67 cases were reported, with a mean annual incidence of 0.01 per 100,000 population.
• Foodborne botulism in Indigenous communities decreased to 46% of cases, compared to 85% in 1990-2005.
• Botulinum neurotoxin type E caused 52% of cases; type A was linked to longer hospital stays and intensive care. Four outbreaks involved commercial products, including carrot juice. Seven deaths were reported.

Conclusions:

• Despite a decrease in cases within Indigenous communities, foodborne botulism remains a concern in Canada.
• Botulinum neurotoxin type A presents a greater clinical burden than types B or E.
• Enhanced clinician awareness is vital for improving diagnosis, aiding investigations, and optimizing patient treatment.