Distribution of Pathogenic Bacteria in Local Specialty Foods in Yan'an, China and Their Impact on Public Health

Abstract

Background: Yan'an in Shaanxi province, China, is celebrated for its traditional specialty foods characterized by unique flavors and artisanal production methods. However, foodborne pathogen contamination remains a critical public health challenge, particularly in surveillance and prevention. Objectives: This study aimed to investigate the distribution of pathogenic bacteria in Yan'an's local specialty foods and assess their potential public health implications between June 2023 and June 2024, providing evidence to strengthen regional food safety policies and management practices. Methods: In accordance with national and provincial food safety standards, we conducted systematic sampling and microbiological testing of five categories of Yan'an specialty foods for pathogenic contamination. Concurrently, foodborne disease incidence data from Yan'an sentinel hospitals were analyzed. A quantitative microbial risk assessment (QMRA) model was employed to quantify health risks associated with detected pathogens and delineate their epidemiological profiles. Results: Among 9,125 food samples analyzed, 771 (8.45%) exceeded permissible hygiene standards. Microbiological identification revealed 546 pathogenic isolates, predominantly Bacillus cereus and Cronobacter spp. Grain and catering foods had the highest infection rates. Foods from convenience stores, retail outlets, farmers' markets, and supermarkets were heavily contaminated. Additionally, surveillance data identified 5,720 foodborne illness cases over the study period, with higher incidence rates observed in immunocompromised individuals, children, and the elderly. Conclusions: Significant pathogenic contamination was detected in Yan'an's specialty foods, particularly grain products, meat derivatives, and catering items. Retail environments such as convenience stores, open markets, and independent vendors were identified as high-risk contamination sources. These findings underscore the necessity for targeted food safety interventions, including enhanced hygiene protocols, public education campaigns, and stricter regulatory oversight to mitigate risks, especially among vulnerable populations.