The demilitarized fortress Lunet 3 was suspected to be inhabited by man-infesting chiggers. To study this phenomenon, mice, voles and shrews were caught and studied at four-weekly intervals during two years. A dog was used as a bait every Wednesday. Three species of chiggers were found on the small mammals: Neotrombicula autumnalis (Shaw, 1790), N.japonica (Tanaka, et al. ,l930) and Cheladonta sp. Only N. autumnalis was found to attack dog and man. This species was present on its hosts from the middle of July until the middle of October or November. Its larvae were found on Rattus norvegicus , Apodemus sylvaticus , Clethrionomys glareolus, Sorex araneus , Crocidura russula , Erinaceus europeus , Capra hircus Canisfamiliaris , Homo sapiens and Turdus merula . Major hosts were as follows: C. glareolus and A. sylvaticus . Peak number of N. autumnalis per host include 1100 mites on a bank vole and 700 on a goat. Favoured sides of attachment were inside the ears ( C. glareolus ), on the face ( E. europeus ), between the toes (C. familiaris , C. hircus ), around the anus (A. sylvaticus , C. russula S. araneus and T. merula ), in case of man, those areas where clothing was tight. The chiggers were present in higher numbers in 1975 compared to 1974, this is probably caused by the warmer summer of 1975. N. autumnalis had only one generation per year on Lunet 3. The larvae did not hibernate on their hosts. In the summer of 1973 our attention was drawn to a demilitarized fort inhabited by 17 persons , some of whom complained of an annoying papular urticaria. A pilot study pointed to chiggers as the most likely cause of the trouble. Not much is known of dutch chiggers (Bronswijk ~z Roberti, 1974). Consequently we started an investigation of chiggers collected at the above mentioned fortress in order to discover the species present, to understand their host relationships, their numbers and their host seeking activity.
|Journal||International Journal of Acarology|
|Publication status||Published - 1977|