INTRODUCTION

S. enterica subsp. arizonae (IIIa), S. enterica subsp. diari- zonae (IIIb), S. enterica subsp. houtenae (IV) and S. enterica subsp. indica (VI). Salmonella enterica subsp. enterica con­tains most of the salmonellae that are pathogenic for warm-blooded animals, whereas the others usually affect cold-blooded animals and contaminate the environment.

Salmonellosis is an important zoonosis in the EU; infec­tions in humans are mostly caused by food contaminated with Salmonella spp. In addition, environmental contami­nation can be an important source of infection for humans and animals, and in particular for wildlife. Contamination of the natural environment is frequently as a result of human activities, such as livestock farming and waste disposal.

Wildlife can play an important role in the epidemiology of Salmonella infection, and can act as an indicator of environmental contamination and as a maintenance host. Ingestion of contaminated water and food is the most likely route of infection for wildlife; for example, raptors and carnivores consuming infected carcasses can become infected themselves and spread Salmonella in their habitat, often as subclinical carriers. Salmonellosis in wildlife can be a health threat for humans and domestic animals; surveillance programmes in wildlife can be useful to improve our understanding of the epidemiology of Salmo­nella infection and contribute to the multidisciplinary approach to a global problem.

Infectious Diseases of Wild Mammals and Birds in Europe, First Edition. Edited by Dolores Gavier-Widen, J. Paul Duff, and Anna Meredith. © 2012 Blackwell Publishing Ltd. Published 2012 by Blackwell Publishing Ltd. Material authored by Paul Holmes remains Crown Copyright.