Spatial Lyme borreliosis risk assessment in north-eastern Italy

The risk exposure to Lyme borreliosis in the Friuli Venezia Giulia region, in north-eastern Italy, was investigated on the basis of the abundance of infected ticks. A total of 2620 questing Ixodes ricinus ticks were collected at 25 sampling sites during spring 2005 and 2006, and nymphs and adult females were examined for Borrelia burgdorferi. The distribution of infected ticks was analysed in relation to a set of environmental parameters obtained from satellite, climatic, topographic, and biotic data. A multiple linear regression model was developed to predict the abundance of infected ticks and using GIS facilities, it was possible to elaborate an infected tick distribution map.