Mitigating airborne pathogen risks in a full-scale meat processing facility

Foodborne illnesses caused by Shiga toxin-producing Escherichia coli (STEC) and Salmonella represent a major public health concern, particularly in meat processing facilities where bioaerosols generated during processes like carcass spraying and dehiding can lead to contamination. In this study, we assessed airborne concentrations of STEC and Salmonella at multiple locations within a full-scale meat processing facility using quantitative polymerase chain reaction (qPCR) and Illumina MiSeq sequencing. Additionally, we utilized computational fluid dynamics (CFD) simulations to model airflow within the facility and evaluated the effectiveness of air curtains in mitigating the transfer of bioaerosols between high-risk (dehiding and tripe) and low-risk (chiller and fabrication) areas. qPCR results showed that pathogen concentrations in the dehiding rooms were 126 GCN/m³ for STEC and 105 GCN/m³ for Salmonella during spring, with levels rising significantly in summer (2198 GCN/m³ for STEC and 1799 GCN/m³ for Salmonella). Simulated airflow patterns revealed that entrained bioaerosols could be transported from unclean to clean areas, increasing the risk of cross-contamination. The use of air curtains effectively reduced this spread by creating barriers between high- and low-risk areas. Our findings suggest that bacterial survivability and aerosolization was enhanced in summer, highlighting the critical role of environmental factors and airflow management in controlling contamination risks. This study demonstrates the value of integrating experimental data with CFD simulations to assess pathogen spread and identify effective mitigation strategies in meat processing facilities.