The recent outbreak of disease caused by a novel H1N1 virus has focused global attention on the threat of a new influenza pandemic. Recent years have also seen unprecedented outbreaks of avian influenza A viruses. In particular, highly pathogenic H5N1 viruses have not only resulted in widespread outbreaks in domestic poultry, but have been transmitted to humans resulting in numerous fatalities. The rapid expansion in the geographic distribution of these novel viruses raises the risk that such a virus could cause a global pandemic with high morbidity and mortality. An effective influenza vaccine represents the best approach to prevent and control such an emerging pandemic. However, current influenza vaccines are directed at existing seasonal influenza viruses, which have limited antigenic relationships to the newly emerging virus strains. Concerns about pandemic preparedness have greatly stimulated research activities to develop effective vaccines for pandemic influenza viruses, and to overcome the limitations inherent in current approaches to vaccine production and distribution. These limitations include the use of embryonated chicken eggs as the substrate for vaccine production; which is time-consuming and could involve potential biohazards in growth of new virus strains. Other limitations... more on http: //springer.com/978-3-540-92164-6