Mitigating between-farm disease transmission through simulating vehicle rerouting and enhanced cleaning and disinfection protocols.

Abstract

The role of contaminated vehicles and the effectiveness of preventive strategies, such as cleaning and disinfection (C&D), in spreading infectious diseases among commercial swine farms under field conditions remains largely unexplored. This study aimed to reduce the risk of between-farm disease transmission through vehicle contacts by rerouting vehicles while considering C&D events and effectiveness. Vehicles were ranked based on specific criteria, including disease status of visited farms, vehicle contact network communities, C&D events, and shipment time efficiency. The rerouting system showed that, even when C&D was utterly inefficient, it reduced up to 42 % of the contacts between infected and uninfected farms via vehicle movements and 17 % of the total number of interactions between farms from distinct network communities. The rerouting efficacy increased with a C&D effectiveness of 100 %, reducing up to 100 % contacts between infected and uninfected farms and between farms from distinct network communities. Despite the potential benefit of preventing disease dissemination between the farms, the rerouting system increased by up to 81 % in C&D events and up to 54 % in distance traveled per vehicle. Ultimately, we have demonstrated that a rerouting vehicle system holds potential as an additional strategic tool for preventing and controlling the spread of diseases among farms through vehicle movements; however, given the additional time and effort required, its cost-benefit will depend on the severity of the disease being mitigated.