Summary of Awards to Date

On-farm evaluation of the prevalence of human enteric bacterial pathogens during the production of melons in California


Mar. 1, 2012 - Sep. 30, 2012

Award Number


Funding Agency

Center for Produce Safety

Amount Awarded



Trevor Suslow, Ph.D.
University of California, Davis


The overall objective of this study will be the execution of a preliminary longitudinal survey of melon contamination with human bacterial pathogens in each district of California production, including upper and lower San Joaquin Valley, Kern, Blythe, and Brawley. Since 1990, cantaloupes have been associated with 36 outbreaks and pathogen-based recalls recorded in the public health records in the United States from domestic and imported melons. Among these incidents, various Salmonella has been predominantly linked to these outbreaks and recalls. Recently, a multistate outbreak related to infected cantaloupes with Listeria monocytogenes resulted, as of September 29, 2011, in 146 cases, 31 deaths, and one miscarriage in 28 states. Three guidance documents; Minimizing the risk of foodborne illness associated with cantaloupe production and handling in California: Overview of Industry Practices and Risk Assessment (2003). The Commodity Specific Food 6 February 2012 Safety Guidelines for the Melon Supply Chain (CS‐GAPs; 2005) and FDA 2009 Guide to Minimize Microbial Food Safety Hazards of Melons identify concerns and provide recommendations for food safety practices that are intended to minimize the microbiological hazards associated with melon production. In addition, the recently published Food Safety Modernization Act, has pointed out the need for science based food safety standards that consider naturally occurring hazards during food production, so adequate preventive controls could be established. Strategic and intelligent design of preventive controls, industry guidance or mandatory marketing orders, and regulatory and enforcement standards depend on access to publically-available data on pathogen prevalence, geographic distribution, seasonality, and association with commodity specific practices and risk factors. Thus, systematic scientific studies are needed to identify critical points where melons are most prone to detectable levels of contamination. In addition, the natural prevalence of foodborne pathogens on melons in the major production regions has been recently identified, by the supply and retail industry as a research priority. This data is viewed as vital to establish meaningful and verifiable industry-wide food safety standards regarding the microbial quality during melon production and marketing to regain and enhance consumer confidence so badly shaken by the listeriois tragedy.