Vehicle and Equipment Decontamination During Outbreaks of Notifiable Animal Diseases in Cold Weather

The objective of this study was to evaluate various procedures for decontamination of vehicles and equipment during outbreaks of notifiable animal diseases in cold weather. The evaluation was done in 4 field trials held in outdoor operational settings in Canada, at ambient temperatures from –2°C to 11°C. Procedures included various combinations of dry cleaning, wet cleaning, disinfection, and final rinsing. Geobacillus stearothermophilus spores and infectious bursal disease virus (IBDV) were used as surrogates for bacterial and viral pathogens, particularly Bacillus anthracis spores and foot-and-mouth disease virus. Spores and viruses were suspended in a light organic soil preparation, inoculated onto stainless-steel disks, and covered with a heavy soil preparation. Inoculated disks were attached to various surfaces of farm vehicles and equipment. In all field trials, spore and IBDV reduction was greater (P < .05) on disks where the soil was completely removed, as compared with only partially removed. Greater (P < .05) spore and IBDV reduction was seen when disinfection and final rinse steps were included than when not included after dry and wet cleaning in 3 of 3 and 1 of 3 field trials, respectively. A wet-cleaning step before application of a disinfectant increased (P < .05) spore and IBDV reduction versus no wet cleaning. The results provide evidence that vehicle and equipment decontamination in cold weather could be significantly improved by thorough removal of organic matter to enhance disinfection and elimination of disease agents.