1. Laboratory of Hygiene and Environmental Protection, Department of Medicine, Democritus University of Thrace, 68100 Alexandroupolis, Greece
2. Infectious Diseases Service, Lausanne University Hospital, University of Lausanne (CHUV), 1011 Lausanne, Switzerland
3. Laboratory of Animal Health, Food Hygiene and Quality, Department of Agriculture, University of Ioannina, 47132 Arta, Greece