1The Persian Gulf Tropical Medicine Research Center, The Persian Gulf Biomedical Sciences Research Institute, Bushehr University of Medical Sciences, Bushehr, Iran. 2Department of Biological Sciences, North Dakota State University, Fargo, North Dakota USA. 3Iranian Tissue Bank and Research Center, Tehran University of Medical Sciences, Tehran, Iran. 4Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 5Department of Medical Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 6Department of Immunology and Allergy, Faculty of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran. 7National Influenza Center, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.