1. Department of Biological and Chemical Work Environment, National Institute of Occupational Health, Oslo, Norway;
2. Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway;
3. Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway;
4. The Shraga Segal Department of Microbiology, Immunology, and Genetics, The Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel