Fig. 1From: Better influenza vaccines: an industry perspectiveTimeline of current influenza vaccine production methods. Schematic overview of egg-based, cell-based and protein-based influenza vaccine production. Vaccine strains that match circulating influenza viruses for the upcoming flu season are selected by the World Health Organization (WHO) Global Influenza Surveillance and Response System (GISRS). High yielding vaccine strains for egg- or cell-based production are generated by either classic or reverse genetic reassortment. These adapted viruses go into mass production, either in embryonated chicken eggs or MDCK cells with a production timeline of approximately six to eight months. In recombinant HA (rHA) vaccines, the HA sequence is cloned into baculovirus and expressed by insect cells, significantly shortening production timeBack to article page