1. Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
2. Department of Medical Education, Center for Infectious Disease, Inflammation and Immunity, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee, USA
3. Department of Microbiology and Immunology, Uniformed Services University, Bethesda, Maryland, USA
4. Department of Mathematics, Faculty of Science, University of Zurich, Zurich, Switzerland