EFSA has published the first scientific assessment in Europe on public health risks posed by pathogens that may contaminate food of non-animal origin. The scientific opinion compares the proportion of human cases reported in outbreaks of food-borne disease, from 2007 to 2011, related to food of non-animal origin with those associated with food of animal origin in Europe. EFSA experts also identified and ranked combinations of foods and pathogens most often linked to foodborne illness from foods of non-animal origin.
Foods of non-animal origin include a wide variety of fruit, vegetables, salads, seeds, nuts, cereals, herbs, and spices. They are an important part of our daily diet. According to the scientific opinion published today by the Panel on Biological Hazards, foods of animal origin continue to be the source of the majority of all documented and reported outbreaks (90%). However the number of outbreaks, human cases, and hospitalisations associated with food of non-animal origin has increased over this period.
Outbreaks associated with these foods tend to involve more human cases but are usually less severe in terms of hospitalisations and deaths than those associated with foods of animal origin. However, when considering trends from 2007 to 2011, showing that outbreaks related to foods on non-animal origin were associated with 10% of outbreaks, 26% of human cases, 35% of hospitalisations and 46% of deaths, one should consider the high health impact of the 2011 sprout-associated outbreak of Shiga-toxin producing Escherichia coli. If data from this large outbreak are excluded, foods of non-animal origin were associated with 5% of all deaths from reported foodborne outbreaks.
Developing a risk ranking model
The Panel developed a model to support risk managers in ranking risks related to foodborne illness from foods of non-animal origin. The top-ranking combination of foods and pathogens (viruses, bacteria or parasites) in the period considered was Salmonella and leafy greens eaten raw followed by the following combinations, all ranked equally: Salmonella and bulb and stem vegetables (such as asparagus, onion, garlic, etc); Salmonella and tomatoes, Salmonella and melons; and pathogenic E. coli and fresh pods, legumes or grains.
As with all models, the resulting analysis has some limitations associated with the data considered.
The Panel used zoonoses monitoring data collected from Member States which provide information on the number and severity of food-borne disease outbreaks across all Member States.
However, the importance of some combinations may be overestimated and additional food/pathogen combinations may be identified if data from future EU monitoring is considered. The model is also likely to underestimate the importance of diseases of a more sporadic nature, such as those due to Listeria monocytogenes or Campylobacter.
EFSA’s scientific opinion recommends the adoption of harmonised terminology when categorising foods for data collection purposes, as well as the collection of additional information on how individual foods are prepared, processed and stored.
In 2013, EFSA will analyse factors contributing to the risks from the pathogen/food combinations identified in the scientific opinion. Where relevant, mitigating options and microbiological criteria will also be investigated for specific pathogen/food combinations.
The risk ranking model used in this opinion was adapted from a model published by the US FDA. It is based on seven criteria: the strength of associations between food and pathogen, incidence of illness, burden of disease, dose-response relationship, consumption, prevalence of contamination and pathogen growth potential during shelf life. Using all the seven criteria, the Panel identified top ranking groups of food/pathogen combination.
The opinion published today complements previous advice of the Biological Hazards Panel published in October 2011, which assessed the risks posed by Shiga toxin-producing Eschericha coli (STEC) and other pathogenic bacteria that may contaminate seeds intended for sprouting and sprouted seeds. EFSA’s scientific advice was requested after the large STEC outbreak, in the spring and summer of 2011. This was caused by a virulent, rare strain of STEC known as O104:H4. This incident highlighted that food of non-animal origin can cause large outbreaks.