Salmonella from a food truck!
My latest update on Places or Things You Should Not Eat now includes lunch from food trucks. The latest Centers for Disease Control and Prevention brought this case study on an outbreak of Salmonella Enteritidis infections in Alberta, Canada. During the period from October 2010 to February 2011, a total of 91 cases were reported to the local department of health. Initial epidemiological work indicated that all patients reported an association with mobile food-service operations that delivered to various worksites in the region. Ultimately, a single catering company was implicated in the outbreak. Of the total, 85 of the patients reported consuming food prepared by the company, and the remaining 6 patients were employees of the company. Public health officials concluded that the outbreak was due in part to the catering company’s use of illegally sourced eggs in food preparation, as well as employees with Salmonella infections who further spread the disease through poor hygiene practices.
Once the source of the outbreak was tracked to the implicated catering company (which has been unnamed, and my Google skillz have been unable to turn up), stool samples from employees were screened for subclinical Salmonella infection, and infectious workers were removed from food preparation duties until deemed non-infectious. Further measures taken were safe food preparation training instruction for all employees, a complete cleaning and disinfection of the site, and the implementation of third party developed safety plan.
Editorial comments by the CDC note that at least 6000 laboratory confirmed cases of Salmonella Enteritidis are reported annually. This compares to the 42,000 in the United States, which when comparing the 10-fold difference in population is a rate per 100,000 people of about half that found in Canada. Eggs are the most frequent vehicle for transmission of Salmonella, and improper food handling procedures result in human contamination. This case was most likely prolonged in comparison to many outbreaks of Salmonella, due to shedding of bacteria from symptomatic and asymptomatic food workers.