Abstract

Porcine Epidemic Diarrhea Virus (PEDV) is a significant pathogen impacting global swine health. Contaminated fomites and vehicle movements are known to contribute to farm-to-farm PEDV spread, yet the effectiveness of cleaning and disinfection (C&D) protocols in reducing dissemination risk via vehicles and trailers has been unclear. This study utilized swine industry data to assess the frequency of PEDV RNA contamination on vehicles and trailers before and after C&D. Researchers collected 2,004 environmental RNA samples from truck cabins, trailers, and tires of four different vehicle types (crew trucks, feed trucks, pigs-to-farm trucks and trailers, and pigs-to-market trucks and trailers) at three C&D sites in eastern North Carolina. Samples were taken before and after C&D using two commercial disinfectants at varying concentrations. An in-house RT-qPCR assay was employed to detect the presence of PEDV RNA. Results indicated that pigs-to-market trucks hauling live pigs were most frequently contaminated with PEDV, with 79.17% of trailers testing positive before C&D and 88.52% after C&D. Feed trucks showed the least contamination, with 8.19% of tires positive before C&D and 15.12% after C&D. The study also demonstrated that a combination of quaternary ammonium and glutaraldehyde was more effective at eliminating detectable PEDV RNA compared to advanced hydrogen peroxide. Furthermore, truck cabins were found to be as contaminated as the exterior of the vehicles. These findings suggest that vehicle biosecurity measures should be re-evaluated and modified to effectively prevent the spread of PEDV.