Brad Gilbertson1, Kanta Subbarao2,3. 1. Department of Microbiology and Immunology, The University of Melbourne, Melbourne, Victoria, Australia. 2. Department of Microbiology and Immunology, The University of Melbourne, Melbourne, Victoria, Australia. kanta.subbarao@influenzacentre.org. 3. WHO Collaborating Centre for Reference and Research on Influenza at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia. kanta.subbarao@influenzacentre.org.