Selection of influenza vaccine strains and developing pandemic vaccines.

The WHO Influenza Surveillance Programme has recently celebrated 50 years of success. The programme provides representative influenza viruses for antigenic and genetic analysis and from this information, the WHO is able to make recommendations on vaccine composition. The WHO has also a key important role to play in detecting new influenza pandemic viruses and advising on suitable vaccine strains and their use. Experience in developing vaccines for pandemics or pandemic alerts in the past, has informed us that there are considerable problems to solve, not least of which is the fact that the conventional vaccines used throughout the world are unlikely to be effective in the face of a pandemic. Different strategies need developing and testing, so that we are adequately prepared.