A novel approach to mapping and calculating the rate of spread of endemic bovine tuberculosis in England and Wales

• Published in: Spatial and spatio-temporal epidemiology Vol. 13; pp. 41 - 50
• Main Authors: Brunton, L A, Nicholson, R, Ashton, A, Alexander, N, Wint, W, Enticott, G, Ward, K, Broughan, J M, Goodchild, A V
• Format: Journal Article
• Language: English
• Published: Netherlands 01-04-2015
• Subjects: Animals; Cattle; Disease Outbreaks - veterinary; Endemic Diseases - veterinary; England - epidemiology; Geographic Information Systems; Geographic Mapping; Mycobacterium bovis - isolation & purification; Risk Factors; Sensitivity and Specificity; Software; Spatio-Temporal Analysis; Tuberculosis, Bovine - epidemiology; Tuberculosis, Bovine - transmission; Wales - epidemiology; England; Wales; Mapping; Boundary displacement; Endemicity; Bovine tuberculosis; Inverse distance weighting
• ISSN: 1877-5845; 1877-5853
• DOI: 10.1016/j.sste.2015.04.002

A mathematical method for estimating the endemic status of bovine tuberculosis (bTB) in cattle in England and Wales has been developed. 6.25km(2) hexagonal cells were used as the base resolution. Maps were produced for overlapping two-year periods spanning 2001/03 to 2009/11. Distance from a farm to the ten nearest 'Officially Tuberculosis Free status - Withdrawn' incidents within the same time period was measured. Endemic areas were defined as those hexagons containing farms where the 3rd nearest incident occurred within 7km. Temporal spread of endemic bTB was estimated by creating a contour map displaying the spread of endemic bTB over the two-year periods, and using boundary displacement to calculate the rate of spread across each hexagon. A rate was obtained for ∼2300 cells and varied between 0.04km and 15.9km per year (median=3.3km per year). This work will enable further analysis of the factors associated with this expansion.