It is becoming increasingly clear that the distinction between 'basic' and 'applied' research is an outdated classification system with little relevance in today's health sciences - and research into the biology of influenza viruses and influenza infection is a prime example of this paradigm. Research that addresses a number of fundamental questions about the molecular and structural biology of these viruses is crucial for the development of advanced solutions to a number of very practical problems in the prevention and treatment of influenza or in public health efforts to stop an epidemic.
The dysregulated innate immune response of the host is increasingly being recognised as a key factor in the severity of the clinical disease. While many of the projects assembled in this chapter include some research on this important aspect, the detection of virus and host determinants of this non-specific response is the major focus of the recently launched FLUINNATE project. EUROFLU, FLUPATH and INNFLU all tackle - in addition to the innate immune response - several other issues related to the pathogenicity of viruses: They examine the important question of how easily viruses are transmitted from one species to another, including the crucial jump from birds to humans, and which factors are responsible for this species-specificity as well as for the clear tropism of the virus for only a very limited range of cell types within a given organism. Related to this question are studies of virus-host receptor interactions, the contribution of haemagglutinin and neuraminidase proteins to virulence in different species as well as research on cellular mechanisms that regulate the viral replication within the infected cell.
FLUPOL (targeted exclusively on influenza) and VIZIER as a broadbased effort aimed at a number of RNA-viruses (but including influenza as well as other medically relevant viruses), both aim to characterise the structure of core enzymes of the viral replication machinery with a view to finding new targets for antiviral drugs. The RespViruses consortium takes a different approach and studies the innate and acquired immune response of elderly patients to known and newly discovered respiratory viruses also with the goal of developing innovative therapeutics, such as antiviral siRNA-based approaches and strengthening the host's immune response.