title: Modelling the wind-borne spread of highly pathogenic avian influenza virus between farms.
abstract: A quantitative understanding of the spread of contaminated farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms. Here, we develop a model to calculate the quantity of contaminated farm-dust particles deposited at various locations downwind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands. The model is obtained from a Gaussian Plume Model by incorporating the dust deposition process, pathogen decay, and a model for the infection process on exposed farms. Using poultry- and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route. A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 epidemic reveals that the wind-borne route alone is insufficient to explain the observations although it could contribute substantially to the spread over short distance ranges, for example, explaining 24% of the transmission over distances up to 25 km.
authors.affiliation: Department of Epidemiology, Crisis Organization and Diagnostics, Central Veterinary Institute part of Wageningen University and Research Centre, Lelystad, The Netherlands. amos.ssematimba@wur.nl
authors.forename: Amos
authors.initials: A
authors.lastname: Ssematimba
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Hagenaars
authors.forename: Mart C M
authors.initials: MC
authors.lastname: de Jong
mesh_terms: D000393:Air Pollutants; D000818:Animals; D004196:Disease Outbreaks; D004391:Dust; D005585:Influenza in Birds / Q000635:transmission*; D008954:Models, Biological; D008962:Models, Theoretical; D009426:Netherlands; D052638:Particulate Matter; D011200:Poultry / Q000821:virology*; D014919:Wind
chemical_list: D000393:Air Pollutants; D004391:Dust; D052638:Particulate Matter