Abstract
Swine influenza viruses (SIVs) are respiratory viral pathogens of pigs that are capable of causing serious global public health concerns in humans. Because of their dual susceptibility to mammalian and avian influenza A viruses, pigs are the leading intermediate hosts for genetic reassortment and interspecies transmission and serve as reservoirs of antigenically divergent human viruses from which zoonotic strains with pandemic potential may arise. Pandemic influenza viruses emerging after the 1918 Spanish flu have originated in Asia. Although distinct lineages of North American and European SIVs of the H1N1, H3N2, and H1N2 subtypes have been widely studied, less is known about the porcine viruses that are circulating among pig populations throughout Asia. The current review presents a historic account of the epidemiology and genetic evolution of SIVs in this region using data from the PubMed and Influenza Virus Resource databases. The current understanding of contemporary viruses, human infection with SIVs, and the potential threat of novel pandemic strains are described. Furthermore, to best use the limited resources that are available for comprehensive genetic assessment of influenza, consensus efforts among Asian nations to increase epidemiosurveillance of swine herds is also strongly promoted.
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This work was supported through a grant (Grant No.: A103001) from the Korea Healthcare Technology R&D Project by the Ministry of Health & Welfare, Republic of Korea.
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Choi, YK., Pascua, P.N.Q., Song, MS. (2011). Swine Influenza Viruses: An Asian Perspective. In: Richt, J., Webby, R. (eds) Swine Influenza. Current Topics in Microbiology and Immunology, vol 370. Springer, Berlin, Heidelberg. https://doi.org/10.1007/82_2011_195
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