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Estimating reassortment rates in co-circulating Eurasian swine influenza viruses.

ABSTRACT: Swine have often been considered as a mixing vessel for different influenza strains. In order to assess their role in more detail, we undertook a retrospective sequencing study to detect and characterize the reassortants present in European swine and to estimate the rate of reassortment between H1N1, H1N2 and H3N2 subtypes with Eurasian (avian-like) internal protein-coding segments. We analysed 69 newly obtained whole genome sequences of subtypes H1N1-H3N2 from swine influenza viruses sampled between 1982 and 2008, using Illumina and 454 platforms. Analyses of these genomes, together with previously published genomes, revealed a large monophyletic clade of Eurasian swine-lineage polymerase segments containing H1N1, H1N2 and H3N2 subtypes. We subsequently examined reassortments between the haemagglutinin and neuraminidase segments and estimated the reassortment rates between lineages using a recently developed evolutionary analysis method. High rates of reassortment between H1N2 and H1N1 Eurasian swine lineages were detected in European strains, with an average of one reassortment every 2-3 years. This rapid reassortment results from co-circulating lineages in swine, and in consequence we should expect further reassortments between currently circulating swine strains and the recent swine-origin H1N1v pandemic strain.

SUBMITTER: Lycett SJ

PROVIDER: S-EPMC3542128 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Estimating reassortment rates in co-circulating Eurasian swine influenza viruses.

Lycett S J SJ Baillie G G Coulter E E Bhatt S S Kellam P P McCauley J W JW Wood J L N JLN Brown I H IH Pybus O G OG Leigh Brown A J AJ For The Combating Swine Influenza Initiative Cosi Consortium

The Journal of general virology 20120912 Pt 11

Swine have often been considered as a mixing vessel for different influenza strains. In order to assess their role in more detail, we undertook a retrospective sequencing study to detect and characterize the reassortants present in European swine and to estimate the rate of reassortment between H1N1, H1N2 and H3N2 subtypes with Eurasian (avian-like) internal protein-coding segments. We analysed 69 newly obtained whole genome sequences of subtypes H1N1-H3N2 from swine influenza viruses sampled be ...[more]

PMID: 22971819

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Dataset Information

Estimating reassortment rates in co-circulating Eurasian swine influenza viruses.

Publications

Estimating reassortment rates in co-circulating Eurasian swine influenza viruses.

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