1. Sackler Medical School, Tel-Aviv University, Tel-Aviv Israel
2. Infection Control Unit, Meir Medical Center, Kfar Saba, Israel
3. Central Virology Laboratory, Ministry of Health, Chaim Sheba Medical Center, Tel-Hashomer, Israel
4. Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel-Aviv University, Israel
5. Infectious Disease Unit, Meir Medical Center, Kfar Saba, Israel