tamination in defined risk areas might be more realistic and cost efficient. Conclusion We demonstrated the feasibility of small-scale anthelmintic baiting of foxes to reduce E. multilocularis egg contamination in urban areas intensively used by the public for recreational activities, such as gardening or out- door sports. In addition, the lower prevalence of infected voles also reduces the risk of domestic carnivores becom- ing infected by preying on voles and, consequently, the risk for egg transmission to pet animals. Therefore, we rec- ommend that public health policy should focus on such defined areas where the organism is highly endemic to reduce a potential risk for alveolar echinococcosis. Acknowledgments The authors thank Claudia Stieger, Isabelle Tanner, Rita Bosshart, Gioia Schwarzenbach, Sasa Stefanic, and all other col- laborators for help in the extensive field and laboratory work; Christian Stauffer and the game wardens of the city of Zürich for their generous collaboration; and Fabio Bontadina and Paul Torgerson for valuable comments on an earlier draft of the man- uscript. This investigation was carried out within the context of the Integrated Fox Project, an interdisciplinary research project on the dynamics of the fox population in Switzerland. The study was supported by the Swiss Federal Office of Veterinary Medicine, Berne (Projekt Nr. 1.99.03) and the Swiss Federal Office for Education and Science (EchinoRisk Projekt QLK2-CT-2001- 001995 / BBW Nr. 00.0586-2). The study was carried out at the Institute of Parasitology, University of Zürich, Switzerland. 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