¹Department of Social Medicine, Occupational and Environmental Dermatology, University Hospital Heidelberg, Heidelberg, Germany

Correspondence: Dr Elke Weisshaar, Department of Social Medicine, Occupational and Environmental Dermatology, University Hospital of Heidelberg, Thibautstrasse 3, 69115 Heidelberg, Germany. E-mail: elke.Weisshaar@med.uni-heidelberg.de

Received 26 August 2005; Revised 29 October 2005; Accepted 21 November 2005; Published online 12 January 2006.

Abstract

The so-called "forest kindergartens" have been increasingly popular in Germany since the beginning of the 1990s. These are nurseries located in forested areas where children spend all-season full-time outdoors. Fifty-three kindergartens in the state of Baden-Württemberg, Germany participated in this study. In a prospective clinical cohort study, the child's personal data, history, protective parental habits concerning tick bites, number of tick bites, and cases of borreliosis were recorded monthly (March–October 2004) using a questionnaire. Altogether, 1,707 children of 25 "forest kindergartens" (506 children) and 28 conventional kindergartens (1,201 children) were included. The response rate was 75% in "forest kindergartens" and 65% in conventional kindergartens. In the "forest kindergartens", 1,503 tick bites especially on the trunk and on the head were found, whereas 502 tick bites were registered in conventional kindergartens. Sixteen cases of borreliosis were diagnosed (10 in "forest kindergartens", six in conventional kindergarten), most frequently manifesting as erythema migrans. Children attending a "forest kindergarten" have a 2.8 times increased risk of experiencing tick bites and a 4.6 times increased risk of suffering from borreliosis compared to conventional kindergarten in Germany, although protective parental behavior in "forest kindergarten" children was significantly better than that in conventional kindergarten.