The role of genetic analysis in influenza virus surveillance and strain characterisation.

The powerful tools of molecular genetics are being utilised in most areas of influenza research and control activities, including surveillance and strain characterisation of these fast-evolving viruses. In this paper, examples are given of the use of molecular methods in influenza surveillance in Norway, and the need for facilitated rapid exchange of up-to-date genetic data within or outside the existing surveillance networks is discussed. Typically, researchers at the individual national surveillance networks, apart from the data obtained from their own virus strains or through bilateral exchange with colleagues, have access mostly to somewhat outdated published sequences. Enhanced availability of current molecular data within regional and national surveillance systems would result in a much better understanding of the epidemiology while the outbreaks are unfolding, something that would benefit surveillance at all levels.