A questionnaire was designed in order to gather information about bedding material and footbath preparation and maintenance in different productive units across the state. This information was used to plan two experiments. In the first experiment, we tested the effectiveness of footbaths in inactivating highly pathogenic (HP) and low pathogenic (LP) avian influenza (AI) viruses on rubber boots. Surprisingly, quaternary ammonia and phenol + glutaraldehide based footbaths were not able to eliminate HPAI (H5N8) and LPAI (H6N2) live viral particles on boots, while a chlorine based granulated disinfectant was able to destroy the virus at contact. These results demonstrated the potential of AI, particularly HPAI isolate, to persist even if exposed to disinfecting footbaths, which suggest that footbaths, as a single tool, are not capable of preventing pathogen introduction into commercial flocks. In the second experiment, we investigated the persistence of HPAI (H5N8) and LPAI (H6N2) in bedding material and feces obtained from turkey, broiler and egg layer commercial productive units. Samples were collected at different times after spiking the bedding materials and feces with LPAI and HPAI. Results showed that HPAI (H5N8) was more persistent than LPAI (H6N2) in layer feces and bedding material obtained from commercial broilers and turkeys. Live HPAI particles persisted 96 hours in layer feces and 48 hours in broiler and turkey bedding. In contrast, LPAI persisted only 12 hours after being spiked in all the different substrates.
Further research in biosecurity practices such as footbath preparation and maintenance and better understanding of the mechanism of the increased persistence of AI is warranted in order to identify effective litter treatments in destroying live virus in bedding material.