Data on influenza viruses circulating in pig populations worldwide has been shared, but more effort is required for its compilation and analysis. According to the OFFLU SIV group, there is increasing scientific evidence from surveillance and genetic analyses that human seasonal influenza viruses and their variants have historically been introduced to pig populations by humans and are still circulating in different swine populations worldwide.
The analyses of the HA protein of influenza viruses in pigs, a protein which plays a key role in virus-host interactions and in vaccine strain selection for human and animals, showed significant diversity among strains circulating within and between geographic areas.
Proposed new HA gene cluster naming system for designating influenza viruses in pigs
The objective of this new nomenclature system developed and proposed by the OFFLU SIV group is to create a common language to be used by human and animal health sectors to designate swine influenza viruses on a global scale. This system will allow for viruses around the world to be evaluated by a unified set of criteria and their genetic relationships understood in a common context. Such a system is also important for targeting groups of viruses to study for antigenic properties and developing effective human and animal vaccines.
The proposed system is a phylogenetic classification system, distinguishing clusters of viruses that share common genetic characteristics. Therefore, it defines the relationship between the different influenza strains, which are continually evolving. This system enables the assessment of the genetic relationships between influenza viruses circulating in swine among different geographic regions as well as between human and swine seasonal influenza viruses.
July 2014/ OIE.