Posted on August 5, 2011, 10:37 AM
Millions get sick, tens of thousands are hospitalized and over a thousand die each year from food-borne illnesses acquired in the United States. The government agencies involved in monitoring or regulating matters related to food safety usually give us the useful but humdrum advice that we should cook meats at high enough temperatures, wash our produce well, or use separate cutting boards for different categories of foods. There isn't any official advice available if we want to make a decision on which foods to avoid in order to reduce our overall risk from pathogens. It would be useful to have answers to two questions: (i) consumption of which category of foods is most likely to lead to an illness? (ii) which categories of foods contain pathogens that cause the deadliest illnesses? This post offers data to help answer the second question.
- M. B. Batz, S. Hoffmann and J. G. Morris, Jr. Ranking the Risks: The 10 Pathogen-Food Combinations with the Greatest Burden on Public Health. University of Florida, Emerging Pathogens Institute, April 2011. (link, accessed January 1, 2013)
- E. Scallan et al. (Centers for Disease Control and Prevention). Foodborne Illness Acquired in the United States—Major Pathogens. Emerging Infectious Diseases 17(1), January 2011. (link, accessed January 1, 2013)
Even though statistics on illnesses caused by various food-borne pathogens are widely available, very little data is available on which food-pathogen combinations cause these illnesses. This is because it is easier to know if a patient has a Salmonella infection but harder to trace back and isolate the food consumed by the patient that caused the infection. Thankfully for us, the Emerging Pathogens Institute (EPI) of the University of Florida has done the hard work and produced a report estimating the annual number of illnesses, hospitalizations and deaths attributable to each category of food. I used their data (which considers the top 14 pathogens), combined it with the estimates by the Centers for Disease Control and Prevention (CDC) on the total number of illnesses, hospitalizations and deaths (which considers a more comprehensive set of 31 pathogens) to determine the percentage attributable to each food category. The following pie-charts summarize these attributions with my own categorization of vegan, vegetarian and non-vegetarian foods. The multi-ingredient category includes foods such as baked goods, sandwiches, pasta, salads and dressings, where a specific contaminated unprocessed ingredient was not identified (some of which may even be because there was cross-contamination with other foods due to mistakes during handling, preparation and cooking.)
attributable to food category
attributable to food category
It is no surprise that the majority of hospitalizations and the vast majority of deaths from food-borne pathogens are directly attributable to the consumption of animal ingredients. But, there is something else that jumps out at us when we look at these three pie charts together: what is attributable to animal ingredients is larger in the second pie chart than in the first and even larger in the third. For example, only 44% of illnesses are attributable to animal ingredients but 58% of hospitalizations and an amazing 72% of deaths are attributable to animal ingredients. Could it be that there is something nastier about pathogens in animal ingredients than in vegan ingredients? In the following bar graphs, I examine this question more closely for vegan and farmed animal product categories. The bar graphs compare the rates of hospitalizations and deaths for those with illnesses attributable to each food category.
attributable to food category (sources: EPI, CDC)
I had no idea before I plotted these graphs that illnesses attributable to eggs or dairy are among the ones most likely to lead to hospitalization. I did not know that pork and deli meats are among the ones that cause the deadliest illnesses. There are many implications that one can draw from this data for both public health and animal advocacy. What implications do you see?