High prevalence of antibodies against Leptospira spp. in male Austrian adults: a cross-sectional survey, April to June 2009

To assess the distribution of specific antibodies against Leptospira spp. in Austrian adults, we conducted an explorative nationwide cross-sectional serological study in 400 healthy individuals. Antibody titres against Leptospira spp. were determined in a microscopic agglutination test using a panel of 14 serovar cultures. Sera of 18 participants were excluded because the samples were unsuitable for testing; the remaining 382 participants comprised 166 professional soldiers and 216 civilians. Overall, 88 (23%) individuals tested positive in serological screening. The subjects' sera reacted most frequently with serovars Canicola (16.5%) and Hardjo (11.8%). Epidemiological information was obtained from a questionnaire: no correlation was found for area of residence, travel abroad, regular outdoor activities, occupational animal contact, or ownership of companion animals. The proportion of seropositive samples was significantly lower among professional soldiers (15.7%) than among civilians (28.7%) (p=0.003). Our data demonstrate serological evidence of a high rate of exposure to Leptospira spp. among the Austrian population. No increased risk of exposure to Leptospira spp. was detected in military personnel.