1. Communicable Diseases Epidemiology Service, Croatian National Institute of Public Health, Zagreb, Croatia.
2. Department of Virology, Croatian National Institute of Public Health, Zagreb, Croatia; School of Medicine University of Zagreb, Zagreb, Croatia.
3. Department of Infectious Diseases, General Hospital “Dr Josip Bencevic”, Slavonski Brod, Croatia.
4. Department of Infectious Diseases, Clinical Hospital Centre, Osijek, Croatia.
5. Department of Microbiology and Infectious Diseases with Clinic, Faculty of Veterinary Medicine University of Zagreb, Croatia.
6. Croatian Veterinary Institute, Regional Veterinary Institute Split, Split, Croatia.
7. Epidemiology Service, Brod-Posavina County Institute of Public Health, Slavonski Brod, Croatia.
8. National Reference Center for West Nile Disease, Istituto G. Caporale Teramo, Teramo, Italy.