Geospatial field applications within United States Department of Agriculture, Veterinary Services.

Epidemiologists, veterinary medical officers and animal health technicians within Veterinary Services (VS) are actively utilising global positioning system (GPS) technology to obtain positional data on livestock and poultry operations throughout the United States. Geospatial data, if acquired for monitoring and surveillance purposes, are stored within the VS Generic Database (GDB). If the information is collected in response to an animal disease outbreak, the data are entered into the Emergency Management Response System (EMRS). The Spatial Epidemiology group within the Centers for Epidemiology and Animal Health (CEAH) has established minimum data accuracy standards for geodata acquisition. To ensure that field-collected geographic coordinates meet these minimum standards, field personnel are trained in proper data collection procedures. Positional accuracy is validated with digital atlases, aerial photographs, Web-based parcel maps, or address geocoding. Several geospatial methods and technologies are under investigation for future use within VS. These include the direct transfer of coordinates from GPS receivers to computers, GPS-enabled digital cameras, tablet PCs, and GPS receivers preloaded with custom ArcGIS maps - all with the objective of reducing transcription and data entry errors and improving the ease of data collection in the field.

Geospatial analysis and modelling in the prevention and control of animal diseases in the United States.

Geospatial analysis of disease investigation data improves data standardisation and validation and enhances pathogen detection. Grid-based surveillance systems for Newcastle disease in southern California and for bovine tuberculosis on Molokai Island, Hawaii, demonstrate the importance of this approach to operational planning. In addition, as shown by a bovine tuberculosis study in wildlife on Molokai Island, a lattice grid can be used to develop zonal strategies for disease regulatory actions. In risk mapping, disease risk distribution is compared with the distribution of risk factors to identify potential determinants of risk. This process is being applied to North American waterfowl migratory routes to identify geographic areas with high concentrations of migratory waterfowl so that a spatially targeted sampling strategy for use in surveillance operations can be designed. Finally, while farm location data are needed to model pathogen spread through susceptible animal populations, this information is generally unavailable to analysts and modellers. Recently, a farm location and animal population simulator application was developed in which agricultural census data is distributed to create a farm location dataset representative of an agricultural commodity within a specific geographic area.

The evolution of internet-based map server applications in the United States Department of Agriculture, Veterinary Services.

The internet is used increasingly as an effective means of disseminating information. For the past five years, the United States Department of Agriculture (USDA) Veterinary Services (VS) has published animal health information in internet-based map server applications, each oriented to a specific surveillance or outbreak response need. Using internet-based technology allows users to create dynamic, customised maps and perform basic spatial analysis without the need to buy or learn desktop geographic information systems (GIS) software. At the same time, access can be restricted to authorised users. The VS internet mapping applications to date are as follows: Equine Infectious Anemia Testing 1972-2005, National Tick Survey tick distribution maps, the Emergency Management Response System-Mapping Module for disease investigations and emergency outbreaks, and the Scrapie mapping module to assist with the control and eradication of this disease. These services were created using Environmental Systems Research Institute (ESRI)'s internet map server technology (ArcIMS). Other leading technologies for spatial data dissemination are ArcGIS Server, ArcEngine, and ArcWeb Services. VS is prototyping applications using these technologies, including the VS Atlas of Animal Health Information using ArcGIS Server technology and the Map Kiosk using ArcEngine for automating standard map production in the case of an emergency.