• On June 5, 2024, FDA announced preliminary findings from a nearly 5-year study of E. coli, including Shiga toxin-producing E. coli (STEC), and Salmonella pathogens in the Southwest agricultural region. The study was conducted in conjunction with a number of partners in the region and in the leafy green industry.  
  • These pathogens are a major cause of food-born illness in leafy greens and the study was launched following a major food-born illness outbreak in Yuma, Arizona which was linked to E. coli 0157:H7 (a STEC serotype). Over the course of the study (May 2019 – April 2024), more than 5000 samples were collected from a variety of potential environmental reservoirs, including water, soil, sediment, air, animal fecal material, and wildlife. Whole genome sequencing was performed on samples to determine their genetic relatedness and distribution.
  • The study found that positive results increased with proximity to concentrated animal feeding operations and the data suggests that air, dust, and wind play a role in pathogen transfer. However, birds and other wildlife do not appear to be a significant source of STEC.
  • Continued analysis of the data and its implications is planned and additional details will be presented at the International Association for Food Protection meeting on July 14-17, 2024.