Listeria monocytogenes is a problematic pathogen for cancer patients, with morbidity and mortality rates higher than those in the general population. The neutropenic diet (ND), which is commonly employed to reduce infection risk by excluding raw foods, including fresh produce, remains a subject of controversy. Correspondingly, produce safety communication strategies are largely unstandardized, with patients and caretakers receiving widely different guidelines and materials depending on their institution. Data-driven food safety diets and communication strategies are needed to improve health and quality of life outcomes in this population.This dissertation aimed to resolve these issues: by (i) updating a previous listeriosis risk model to improve accuracy and define limitations, (ii) constructing decision models evaluating outcomes for the ND vs. three alternative produce safety diets, and determining parameters that justify the use of the ND, (iii) using quantitative and qualitative data to understand the produce safety beliefs, barriers, motivators, and behaviors of pediatric cancer patient caretakers, and their feedback on communication strategies, and (iv) combining literature and qualitative pediatric cancer patient caretaker data to formulate communication objectives and a resulting produce safety communication strategy prototype.A previously presented listeriosis risk model for fresh salads was updated to account for tomato contamination from soil, cross-contamination during dump tank washing, and conveyor and waxing surfaces. Main sources of uncertainty and variability and areas lacking data were highlighted, suggesting opportunities for future research. The risk model was then used to build decision models for cancer patients who consume ready-to-eat (RTE) salads. As measured in disability-adjusted life years (DALYs) per person per chemotherapy cycle, outcomes associated with the ND were consistently worse than for alternative, produce-inclusive food safety diets. Furthermore, when fluctuating uncertain and/or variable parameters were used to compute switchover points, the resulting values were unrealistic (e.g., negative probability), meaning that produce-inclusive food safety diets were the favored intervention for the scenarios examined.Subsequently, foodborne illness risk management strategies were explored. Quantitative surveys and qualitative interviews were conducted with pediatric cancer patient caretakers to assess their beliefs, barriers, motivators, and behaviors, with respect to produce safety guidelines. While no significant quantitative relationships were observed between demographic variables and produce safety behavior frequencies, qualitative grounded theory coding led to classification of five caretaker archetypes, with commonalities in guidelines received, child’s health, food safety behaviors previously enacted, and concerns beyond microbial food safety. The existence of these archetypes underscored the prevalent adoption of the ND and the absence of uniformity in produce safety communication materials. Recommendations for information delivery, timing, and material organization were conceived based on caretaker feedback. These recommendations then were integrated with scientific communication literature to develop objectives conducive to a produce safety communication strategy endorsing safe produce preparation, storage, and dietary inclusion. A novel produce safety communication intervention was prototyped based on corresponding tactics.Overall, this work quantitatively and qualitatively supports the adoption of produce-inclusive food safety diets, such as those recommended by the U.S. Food and Drug Administration (FDA) and American Cancer Society (ACS), as a replacement for the ND. It also presents a feedback-driven risk communication strategy for imparting this information.
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