title: Agent-based model for Johne's disease dynamics in a dairy herd.
abstract: Johne's disease is an infectious gastrointestinal disease in ruminants caused by Mycobacterium avium subsp. paratuberculosis that causes diarrhea, emaciation, decreased milk production and eventually death. The disease is transmitted in utero and via milk and colostrums to calves, and fecal-orally to all age classes. Financial losses due to the disease are estimated to be over $200 million in the US dairy industry. The goal of this study was to evaluate the cost effectiveness of control measures based on diagnosis with a sensitive ELISA, EVELISA. An agent-based, discrete time model was developed to simulate Johne's disease dynamics in a US dairy herd. Spatial aspects of disease transmission were taken into account by using six spatial compartments. The effects on disease prevalence were studied with and without transmission routes included in the model. Further, using the model, cost effectiveness of ELISA-based Johne's disease control was evaluated. Using the parameters we collected and assumed, our model showed the initial prevalence of Johne's disease (33.1 ± 0.2%) in the farm increased to 87.7 ± 1.7% in a 10 year-simulation. When ELISA-based control measures were included in the simulation, the increase in prevalence was significantly slowed down, especially when EVELISA was used. However, the level of the prevalence was still higher than the initial level after 10 year simulation even with the ELISA-based diagnostic intervention. The prevalence was further reduced when quarterly ELISA testing was included. The cost analysis showed that the quarterly ELISA and EVELISA testing could bring $44.8 and $51.5/animal/year more revenues, respectively, to a dairy farm.
authors.affiliation: University of Tennessee Institute of Agriculture, 2431 Joe Johnson Drive, 274 Ellington Plant Science Bldg, Knoxville, TN, 37996-4563, USA. jrobins@utk.edu.
authors.forename: Jessica
authors.initials: J
authors.lastname: Robins
authors.affiliation: Capital University, 1 College Ave, Bexley, OH, USA. sbogen@capital.edu.
authors.forename: Sarah
authors.initials: S
authors.lastname: Bogen
authors.affiliation: University of Tennessee Institute of Agriculture, 2431 Joe Johnson Drive, 274 Ellington Plant Science Bldg, Knoxville, TN, 37996-4563, USA. afranci7@utk.edu.
authors.forename: Auldon
authors.initials: A
authors.lastname: Francis
authors.affiliation: Wageningen University, 6708, PB, Wageningen, The Netherlands. westhoek@wisc.edu.
authors.forename: Annet
authors.initials: A
authors.lastname: Westhoek
authors.affiliation: National Institute for Mathematical and Biological Synthesis, University of Tennessee Knoxville, 1122 Volunteer Blvd., Suite 106, Knoxville, TN, 37996-3410, USA. andrew.kanarek@gmail.com.
authors.forename: Andrew
authors.initials: A
authors.lastname: Kanarek
authors.affiliation: National Institute for Mathematical and Biological Synthesis, University of Tennessee Knoxville, 1122 Volunteer Blvd., Suite 106, Knoxville, TN, 37996-3410, USA. lenhart@math.utk.edu.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Lenhart
authors.affiliation: University of Tennessee Institute of Agriculture, 2431 Joe Johnson Drive, 274 Ellington Plant Science Bldg, Knoxville, TN, 37996-4563, USA. seda@utk.edu.
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Eda
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000191:economics / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control*; D003363:Cost Control / Q000191:economics*; D003612:Dairying; D004797:Enzyme-Linked Immunosorbent Assay / Q000191:economics / Q000662:veterinary*; D005260:Female; D008962:Models, Theoretical; D016927:Mycobacterium avium subsp. paratuberculosis / Q000302:isolation & purification*; D010283:Paratuberculosis / Q000191:economics / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control*; D015995:Prevalence