Salmonella Enteritidis Infections Associated with Foods Purchased from Mobile Lunch Trucks — Alberta, Canada, October 2010–February 2011

During October 2010-February 2011, an outbreak of 91 Salmonella Enteritidis (SE) infections in Alberta, Canada, was investigated by a local public health department (Alberta Health Services, Calgary Zone). Index cases initially were linked through a common history of consumption of food purchased from mobile food-vending vehicles (lunch trucks) operating at worksites in Alberta. Further investigation implicated one catering company that supplied items for the lunch trucks and other vendors. In 85 cases, patients reported consumption of food prepared by the catering company in the 7 days before illness. Six patients were employees of the catering company, and two food samples collected from the catering company were positive for SE. Foods likely were contaminated directly or indirectly through the use of illegally sourced, SE-contaminated eggs at the implicated catering facility and by catering employees who were infected with SE. Public health interventions put into place to control the outbreak included screening employees for Salmonella, excluding those infected from food-handling duties, and training employees in safe food-handling procedures. No further outbreak cases were identified after full implementation of the interventions. This investigation highlights the potential for lunch trucks to be a source of foodborne illness and the need for robust regulatory compliance monitoring of lunch trucks and their food suppliers.