What is the impact of Influenza A (H1N1-2009) being a mix of several strains of the flu virus?
Other H1N1 strains (not the 2009 strain) already infect humans every year, and their genes have originated from swine, human and avian sources. This is a characteristic of all human influenza viruses, so just having a hybrid virus with different origins is not a new finding. However, when the hybrid virus appear to change significantly from current strains, the impact on transmissibility and virulence cannot always be predicted, and we need to link the genetic changes to what we observe in the community and in the affected individuals. For Influenza A (H1N1-2009), more epidemiological studies will be needed to better define how easily it spreads or whether it causes more severe disease. Scientists are interested in the hybrid nature of H1N1 because it helps them to track its spread and origin more easily.
