[Protective effect of clothing impregnated with permethrin against D. reticulatus and D. marginatus in an open biotope of central western France].

During the period of major tick activity, in April and May 1998, in the Saint-Maixent l'Ecole area of Poitou, a comparative study was carried out in order to evaluate the protective effect of garments impregnated with permethrin cis/trans 25/75. Three groups of soldiers made up respectively of 208, 218 and 427 men were involved for 2 or 3 days in this experiment. Respectively 107, 107 and 215 wore impregnated uniforms. Out of a total of 319 ticks, 3 were lxodes ricinus, 305 Dermacentor marginatus and 11 D. reticulatus. There was a significant difference in both the intensity (number of ticks per individual, P < 0.0001) and prevalence (number of individuals with ticks, P < 0.001) of ticks on individuals between impregnated and non impregnated uniforms. The repellent effect of permethrin on ticks was observed at the site of preferential tick attachment (normally the head of the host for these two species of Dermacentor in France) where the number of ticks was significantly lower in impregnated uniforms.