Forty five percent of the Israeli population were infected with the influenza B Victoria virus during the winter season 2015-16

// Sivan Sharabi 1, 2 , Ravit Bassal 3 , Nehemya Friedman 1, 2 , Yaron Drori 1, 2 , Hadar Alter 1 , Aharona Glatman-Freedman 2, 3, 4 , Musa Hindiyeh 1, 2 , Daniel Cohen 2 , Ella Mendelson 1, 2 , Tamy Shohat 2, 3 and Michal Mandelboim 1, 2 1 Central Virology Laboratory, Ministry of Health, Chaim Sheba Medical Center, Tel-Hashomer, Ramat-Gan, Israel 2 Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel 3 The Israel Center for Disease Control, Israel Ministry of Health, Tel-Hashomer, Ramat-Gan, Israel 4 Department of Family and Community Medicine, New York Medical College, Valhalla, New York, United States Correspondence to: Michal Mandelboim, email: michalman@sheba.health.gov.il Keywords: influenza B; vaccine; Yamagata; Victoria Received: August 23, 2017      Accepted: November 29, 2017      Published: December 22, 2017 ABSTRACT While infection with influenza A viruses has been extensively investigated, infections with influenza B viruses which are commonly categorized into the highly homologous Victoria and Yamagata lineages, are less studied, despite their considerable virulence. Here we used RT-PCR assays, hemagglutination inhibition assays and antibody titers to determine the levels of influenza B infection. We report of high influenza B Victoria virus prevalence in the 2015–16 winter season in Israel, affecting approximately half of the Israeli population. We further show that the Victoria B virus infected individuals of all ages and that it was present in the country throughout the entire winter season. The vaccine however included the inappropriate Yamagata virus. We propose that a quadrivalent vaccine, that includes both Yamagata and Victoria lineages, should be considered for future influenza vaccination.