The Mexican influenza A virus (H1N1) reminds us that the threat of an influenza pandemic is real. The 1918 Spanish flu virus, also started as a low pathogenic virus that mutated into a highly pathogenic virus within months, causing more than 50 million deaths. The Mexican influenza A virus (H1N1) may follow the same path. FLUPLAN will expand our knowledge of the packaging signals that govern reassortment events between influenza A viruses in general and between the Mexican influenza A virus (H1N1) and circulating human, porcine and highly pathogenic avian influenza A viruses in particular. FLUPLAN will thus lead to fundamental insights in the mechanisms that govern reassortment phenomena, providing a risk assessment concerning the pandemic potential of circulating avian and mammalian influenza A viruses. This will provide us with a panel of possible reassortant viruses of potentially pandemic nature. The MVA vaccine vector system that efficiently induced broad protective immunity against HPAI-H5N1 viruses in macaques, will be used for the preparation of a repository of MVA-H based pandemic vaccine seed viruses.The selection will be based on the reassortant viruses mentioned above, and on a repository of avian influenza viruses of the 16HA subtypes including the Mexican influenza A virus (H1N1) of avian/swine origin. The added value of including a relevant MVA-NP in the immunization schedule to obtain broader and longer protection will be determined in a macaque infection model. Collectively these studies will provide us with a highly versatile system that anticipates on future pandemic events by having seed viruses for vaccine development ready to go on the shelf, for the rapid production of broadly protective pandemic vaccines, which will save time and thus lives.