This publication by J.A. Painter et al. was summarized by Uma Valeti and Nick Genovese, with edits by Vipal Jain. The full, original paper can be accessed here.
Each year, >9 million foodborne illnesses are estimated to be caused by major pathogens acquired in the United States. Preventing these illnesses is challenging because resources are limited and linking individual illnesses to a particular food is rarely possible except during an outbreak. We developed a method of attributing illnesses to food commodities that uses data from outbreaks associated with both simple and complex foods. Using data from outbreak-associated illnesses for 1998–2008, we estimated annual US foodborne illnesses, hospitalizations, and deaths attributable to each of 17 food commodities. We attributed 46% of illnesses to produce and found that more deaths were attributed to poultry than to any other commodity. To the extent that these estimates reflect the commodities causing all foodborne illness, they indicate that efforts are particularly needed to prevent contamination of produce and poultry. Methods to incorporate data from other sources are needed to improve attribution estimates for some commodities and agents.
Purpose of Study
To determine the relative attribution of foodborne illnesses to specific foods as a basis for prioritization of food safety resources.
This paper, authored by the Centers for Disease Control and Prevention, attempts to model the epidemiological carriers of foodborne illness to exclusive, tiered classifications of food commodities. Outbreak pathogens were categorized as bacterial, chemical, parasitic and viral, with several more sub-categories.
271,974 foodborne illnesses were reported in the United States during the period spanning 1998 – 2008, associated with 13,352 foodborne disease outbreaks. 37% of the outbreaks were linked with a single cause. Using these parameters, the authors modelled the commodities accountable for the respective percentage of an estimated ~9.6 million illnesses, ~52 thousand hospitalizations and ~1.5 thousand deaths caused by single pathogens in food commodities each year in the United States.
Land animal commodities were the leading cause of bacterial illness. Aquatic animal commodities were the leading cause of chemical illness. Parasitic illness was led by commodities classified under fruits-nuts and mollusks. Leafy vegetables served as the primary carrier for viral illness.
Discussion & Conclusions
Overall, commodities classified under plants conveyed more foodborne illness, however consumption of commodities within combined aquatic and land animal categories were most likely to result in death from foodborne illness. Particularly, the poultry category was attributed to the most deaths, respectively linked to Listeria or Salmonella poisoning.
The authors discussed, but did not segregate foodborne illness attributable to contamination at various stages in the food distribution chain. For instance, contamination by pathogens may occur prior to, at, or following the point of processing. These considerations may be important for establishing plant-based or cultured alternatives to animal products as a food safety solution.
For instance, contamination of animal products prior to processing would be directly linked to animal production. However, contamination at the point of processing or after may be attributable to cross-contamination from other sources and improper storage. Where specific pathogen-free processes can replace animal production, plant-based or cultured alternatives to animal products might be implemented to reduce food safety risks associated with collective animal commodities. Moreover, contamination of plants by animal production waste streams via irrigation and wash waters are a known source of produce contamination. Thus, wide-scale substitution of plant-based and cultured alternatives for animal products and their production may offer beneficial, collateral effects to reduce the food safety risks of produce commodities as well.