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Volume 12, Number 7—July 2006

Triple Reassortant H3N2 Influenza A Viruses, Canada, 2005

Christopher W. Olsen*Comments to Author , Alexander I. Karasin*, Suzanne Carman†, Yan Li‡, Nathalie Bastien‡, Davor Ojkic†, David Alves§, George Charbonneau¶, Beth M. Henning#, Donald E. Low**, Laura Burton**, and George Broukhanski**
Author affiliations: *University of Wisconsin-Madison, Madison, Wisconsin, USA; †Animal Health Laboratory, Guelph, Ontario, Canada; ‡Canadian Science Centre for Human and Animal Health, Winnipeg, Manitoba, Canada; §Ontario Ministry of Agriculture, Food, and Rural Affairs, Guelph, Ontario, Canada; ¶Swine Services Group, Stratford, Ontario, Canada; #Ontario Ministry of Health and Long Term Care, Clinton, Ontario, Canada; **Ontario Ministry of Health and Long Term Care, Toronto, Ontario, Canada

Main Article

Figure 1

Figure 1. Nucleotide phylogram for the hemagglutinin (HA) genes of A/Swine/Manitoba/12707/05, A/Swine/Alberta/14722/05, A/Swine/British Columbia/28103/05, A/Swine/Ontario/33853/05, A/Turkey/Ontario/31232/05, A/Ontario/RV1273/05, and related reference viruses. The evolutionary relationships among these viruses were estimated by the method of maximum parsimony (PAUP software, version 4.0b10) with a bootstrap resampling method (200 replications) and a fast heuristic search algorithm. Numbers at the nodes of the phylograms indicate the bootstrap confidence levels. Horizontal-line distances are proportional to the minimum numbers of nucleotide changes needed to join nodes and gene sequences. Vertical lines are present to space the branches and labels. The designations I, II, and III identify clusters of viruses previously defined among triple reassortant swine viruses in the United States (4). The viruses described in this report and related viruses are proposed to represent a new cluster IV group of viruses. GenBank accession numbers for the sequences of all reference viruses are provided in parentheses after the virus names.

Main Article

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