PREDICTIVE MAP OF IXODES VICINUS HIGH-INCIDENCE HABITATS AND A TICK-BORNE ENCEPHALITIS RISK ASSESSMENT USING SATELLITE DATA

The main objective of this project was to predict Ixodes ricinus abund ant habitats reliably as a means of tick-borne encephalitis (TBE) risk assessment for the prevention of this disease. The vegetation types w ere used as the indicators of an ecosystem suitable for tick occurrenc e, for TEE virus circulation and, accordingly, for the existence of na tural foci of this infection. Remote sensing methods were used to dete rmine the indicative plant cover. Satellite data covering an experimen tal area of 70 x 70 km in Central Bohemia, the Czech Republic, was acq uired by the Landsat 5 TM scanner. Nine forest classes were recognized in the experimental area by successive supervised and unsupervised cl assifications and identified in a field-checking botanical survey. An epidemiological TEE map based on human cases contracted in the territo ry under study was exploited for the evaluation of risk in particular forest classes. Predictive maps are expressed both in digital and in p rinted forms at a scale of 1:300 000 for an overall risk evaluation an d at a scale of 1 :25 000 for a detailed local orientation. Exp Appl A carol 22: 417-433 (C) 1998 Chapman & Hall Ltd.