Food safety trends in the U.S. and update on pathogenic E. coli

Authors: Fratamico, Pina; BARANZONI, GIAN MARCO - Collaborator

Submitted to: United States-Japan Cooperative Program in Natural Resources (UJNR)
Publication Type: Proceedings
Publication Acceptance Date: 10/1/2016
Publication Date: 11/7/2016
Citation: Fratamico, P.M., Baranzoni, G. 2016. Food safety trends in the U.S. and update on pathogenic E. coli. In: Proceedings of the United States-Japan Cooperative Program in Natural Resources (UJNR), November 7-10, 2016, Honolulu, Hawaii. p. 27-28.

Interpretive Summary:

Technical Abstract: Foodborne Diseases Active Surveillance Network (FoodNet): FoodNet is a main part of the Centers for Disease Control and Prevention’s (CDC) Emerging Pathogens Program and was established in 1995 as a population-based sentinel surveillance system to monitor changes in the incidence of nine pathogens (Campylobacter, Listeria, Salmonella, Shiga toxin-producing E. coli (STEC) O157:H7 and non-O157, Shigella, Vibrio, Yersinia, Cryptosporidium, and Cyclospora), and hemolytic uremic syndrome. FoodNet involves a collaboration among CDC, 10 state health departments, the USDA Food Safety and Inspection Service, and the Food and Drug Administration. The surveillance area covers 48 million people and various states. Each year, FoodNet data and changes in incidence for the preceding year are reported in the CDC Morbidity and Mortality Weekly Report. Preliminary data for FoodNet 2015 are available at https://www.cdc.gov/foodnet/reports/prelim-data-intro.html. Salmonella and Campylobacter were the most frequent causes of infection, which is consistent with previous years. The incidence of Campylobacter, STEC O157:H7, Listeria, Shigella, Yersinia, and Cryptosporidium declined since 1996, Salmonella infections remained stable, although the incidence of S. Typhimurium infections decreased, and the incidence of Vibrio and Cryptosporidium increased. The increase in incidence of Cryptosporidium infections may be due to increased testing. The reasons for increased incidence of Vibrio infections are not known, but warming of coastal waters, consumption of raw shellfish, and ineffective control measures may be contributing factors. The increased use of culture-independent diagnostic tests has revealed an increase in infections by specific pathogens; however, without an isolate, the interpretation of public health surveillance data and ability to monitor progress toward prevention efforts are hindered. Emerging pathogens: Emerging infectious diseases are those in which the incidence in humans has increased within the past 20 years or threatens to increase in the near future. Factors involved in the increase of food-borne diseases and in the emergence/re-emergence of food-borne pathogens are shown in Table 1. There are a number of challenges to food safety such as changes in food production and food supply and in environmental conditions leading to food contamination; increasing number of multistate (and multi-country) food-borne outbreaks; and new and emerging microbes, toxins, and antimicrobial resistance patterns. There are also new vehicles of infection, and these include prepackaged raw cookie dough, flour, and STEC O157:H7 in pork, crabmeat, and hazelnuts, and S. Typhimurium in peanut butter that have caused food-borne illness. There are pathogenic groups of E. coli that have been described, and these include the Shiga toxin-producing, enteropathogenic, enterotoxigenic, enteroaggregartive, enteroinvasive, and diffusely adherent E. coli defined by the type of diarrheal illness they cause and the virulence genes they carry. Extraintestinal pathogenic E. coli (ExPEC) cause diseases outside of the GI tract, and food, particularly poultry can carry ExPEC strains that cause human illness (1). In recent years hybrid strains of E. coli have emerged with combinations of virulence genes from different pathotypes. This includes the enteroaggregative hemorrhagic E. coli (EAHEC) and strains that carry ExPEC and STEC genes, including serotype O80:H2 that caused bacteremia, as well as hemolytic uremic syndrome (2). There are many other emerging pathogens, including non-jejuni/coli species of Campylobacter that have caused human illness and that are associated with food (3). Table 1. Factors related to increase in food-borne illness and the emergence/re-emergence of food-borne pathogens Human demographic Related 1. Increase in world populati