title: Seroprevalence and GIS-supported risk factor analysis of Fasciola hepatica infections in dairy herds in Germany.
abstract: A total of 20 749 bulk tank milk (BTM) samples was collected in November 2008 from all over Germany, corresponding to 20.9% of all German dairy herds. The BTM samples were analysed for antibodies against Fasciola hepatica using the excretory-secretory (ES) ELISA. A geospatial map was drawn to show herd prevalences per postal code area. Various spatial risk factors were tested for potential statistical associations with the ELISA results in logistic regression supported by a geographical information system (GIS). The mean seroprevalence was 23.6% and prevalences in different German federal states varied between 2.6% and 38.4%. GIS analysis revealed statistically significant positive associations between the proportion of grassed area and water bodies per postal code area and positive BTM ELISA results. This can be explained by the biology of the intermediate host, the amphibious snail Galba (Lymnea) truncatula and the pasture-borne nature of fasciolosis. The full logistic regression model had a Pseudo-R 2 of 22%, while the final model obtained by controlled stepwise model building revealed a Pseudo-R 2 of 14%, indicating that additional, unrecorded factors and random effects contributed substantially to the occurrence of positive ELISA results. Considering the high seroprevalences in some areas and the economic impact of fasciolosis, farmers and veterinarians should be strongly advised to implement effective liver fluke control programmes.
authors.affiliation: Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany.
authors.forename: Birte
authors.initials: B
authors.lastname: Kuerpick
authors.forename: Franz J
authors.initials: FJ
authors.lastname: Conraths
authors.forename: Christoph
authors.initials: C
authors.lastname: Staubach
authors.forename: Andreas
authors.initials: A
authors.lastname: Fröhlich
authors.forename: Thomas
authors.initials: T
authors.lastname: Schnieder
authors.forename: Christina
authors.initials: C
authors.lastname: Strube
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000469:parasitology; D003612:Dairying; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005210:Fasciola hepatica / Q000276:immunology*; D005211:Fascioliasis / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D005260:Female; D040362:Geographic Information Systems; D005858:Germany / Q000453:epidemiology; D016015:Logistic Models; D008892:Milk / Q000469:parasitology*; D015999:Multivariate Analysis; D015995:Prevalence; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012908:Snails / Q000276:immunology
chemical_list: D000909:Antibodies, Helminth