1. Department of Medical Microbiology, Academic Medical Center, Amsterdam
2. Animal Sciences Group (ID-Lelystad), Lelystad
3. Department of Medical Microbiology & Infectious Diseases, Erasmus MC, Rotterdam
4. The Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
5. Analytic Diagnostic Center, Curaçao, Netherlands Antilles
6. TNO Voeding, Voedingsmiddelenmicrobiologie, Zeist, The Netherlands