Echinococcus multilocularis: secondary poisoning of fox population during a vole outbreak reduces environmental contamination in a high endemicity area.

• Main Authors: Raoul, F., Michelat, D., Ordinaire, M., Décoté, Y., Aubert, M., Delattre, P., Deplazes, P., Giraudoux, P.
• Other Authors: Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté COMUE (UBFC)-Université Bourgogne Franche-Comté COMUE (UBFC), Laboratoire d'études et de recherches sur la rage et la pathologie des animaux sauvages, Agence Française de Sécurité Sanitaire des Aliments (AFSSA), Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institute of Parasitology
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2003
• Subjects: Animals; Echinococcosis; Echinococcus; Endemic Diseases; France; Pest Control; 4-Hydroxycoumarins; Arvicolinae; Environmental Exposure; Foxes; Population Density; Rodenticides; MESH: 4-Hydroxycoumarins; MESH: Animals; MESH: Population Density; MESH: Rodenticides; MESH: Arvicolinae; MESH: Echinococcosis; MESH: Echinococcus; MESH: Endemic Diseases; MESH: Environmental Exposure; MESH: Foxes; MESH: France; MESH: Pest Control; [SDV.EE]Life Sciences [q-bio]/Ecology; environment; Microtus arvalis
• Online Access: https://hal.science/hal-00340072

International audience This paper describes the role of fox population level on Echinococcus multilocularis infection in foxes in a highly endemic area in eastern France. Fox population level was monitored by spotlight survey at Le Souillot from 1989 to 2000, and from 1992 to 2000 at Chemin, a control site located in a low endemic area. The infection level of the fox population was estimated at Le Souillot from winter 1995 to winter 1999 using a coproantigen ELISA performed on faeces collected in the field. Population biomass of intermediate hosts (Microtus arvalis and Arvicola terrestris) was monitored using index methods from 1995 to 1999. At Le Souillot, a significant decline in the fox population level was recorded after spring 1997 (P<0.001), and the population level remained low until 2000. The decline occurred when 31% of the grassland area was treated with bromadiolone, an anticoagulant used at a large scale for the control of A. terrestris population outbreaks. No decline of population was recorded at Chemin, where bromadiolone was not used for rodent control. Significant differences among ELISA OD distributions in fox faeces were recorded for the five winters under study at Le Souillot (P=0.0004). The median of ELISA OD distribution was 0.209 and 0.207 before the population decline (winter 1995 and 1996, respectively), significantly increased to 0.306 just after the decline (winter 1997), and then significantly decreased to 0.099 and 0.104 afterwards (winter 1998 and 1999, respectively). Therefore, the decrease in infection level occurred during winter 1998, 1 year after the population decline, when the intermediate host biomass in the field was at its highest. These results suggest a complex dependence between the fox population level and E. multilocularis infection in a high endemicity area. Alternative ways to control fox population as a way to reduce E. multilocularis transmission in a given area are discussed.