Bluetongue Spread Modelling

Bluetongue Virus (BTV) is endemic in Northern Australia but clinical disease in sheep has not been seen, despite the fact that some isolates are know to be pathogenic in Australian sheep. The future distribution of BTV in Australia may be influenced by changes to weather patterns, the incursion of new competent insect vectors (species of Culicoides midge), the incursion of new strains of BTV, or by evolution of the virus itself. The spread of BTV in Northern Europe and it's previously unforseen ability to become endemic in cooler climates has resulted in increased research activities in virus transmission, on detailed reporting of these outbreaks and in the initiation of modelling studies (in the UK, for example). Modelling studies aim to develop techniques to determine the disease spread characteristics (e.g. scale and geographical extent) following an incursion. They would also be used to determine the effectiveness of interventions, such as vaccination, culling and movement bans, in achieving disease free status following an incursion into a previously disease free area. Appropriate modelling technology is important from a biosecurity perspective, given that "real world" experimentation is infeasible. The research challenge is to develop models which are as realistic as possible, capturing the fundamental features of the underlying physical system. Input from a reference group of insect vector and disease experts will be a key component of this project.

Meat and Livestock Australia Project Grant:

Project Title: Development of Simulation Technology for Modelling Bluetongue Disease Spread Behaviour

This project is developing a simulation model for BTV in Australia to predict the future location of the disease following introduction of a novel virus strain or an incursion into a previously disease free area, and to allow for the determination of optimal control or eradication policies. The simulation technology will be available for use in "real time" to predict disease spread via movement of infected animals and/or midge vectors. This project is applying novel infectious disease modelling methods developed by the Senior Investigator and colleagues at UWA together with techniques which we have developed for capturing the effect of wind on the spread of bushfires. The resulting simulation toolset will be available for use by biosecurity and animal disease managers within state and federal agriculture departments. It will be useful in improving national infrastructure for BTV control and to prepare for BTV incursions in currently disease free areas, together with being available for providing input into planning to achieve disease freedom in areas currently affected (e.g. the Pilbara, WA).

Publication:
Kelso, J.K., Milne GJ, 2014 A Spatial Simulation Model for the Dispersal of the Bluetongue Vector Culicoides brevitarsis in Australia PLOS One, 9(8), e104646