Serologic and genetic characterization of North American H3N2 swine influenza A viruses.
The H3N2 subtype of influenza A viruses isolated from pigs in the United States and Canada has shown both genetic and antigenic diversity. The objective of this study was to determine the serologic and genetic characteristics of contemporary strains of these viruses. Genetic analysis of 18 reference strains and 8 selected strains demonstrated differences in 1% to 9% of the nucleotides of the hemagglutinin (HA) gene. Phylogenetic analysis of the HA gene revealed 3 genetic clusters, as well as divergence of cluster III viruses from a cluster III prototype virus (A/Swine/Illinois/21587/99). By means of 1-way cross-hemagglutination inhibition with antiserum against 5 field isolates and 3 vaccine viruses, most of 97 isolates tested could be placed in 1 of 3 serogroups. The several isolates that did not react with any antiserum were in genetic cluster III, which suggests that continuous antigenic drift in cluster III may have resulted in virus variants. The efficacy of commercial vaccines against these virus variants should be evaluated with vaccination and challenge studies.
Gramer
Marie René
MR
Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1333 Gortner Avenue, St. Paul, Minnesota 55108, USA. grame003@umn.edu
Lee
Jee Hoon
JH
Choi
Young Ki
YK
Goyal
Sagar M
SM
Joo
Han Soo
HS
D000595:Amino Acid Sequence; D000818:Animals; D000940:Antigenic Variation; D001483:Base Sequence; D016000:Cluster Analysis; D003429:Cross Reactions; D014644:Genetic Variation; D006385:Hemagglutination Inhibition Tests; D053122:Influenza A Virus, H3N2 Subtype / Q000145:classification* / Q000235:genetics*; D008969:Molecular Sequence Data; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D016415:Sequence Alignment; D012703:Serotyping / Q000662:veterinary; D013552:Swine; D013553:Swine Diseases / Q000821:virology*
D012367:RNA, Viral
Science. 1999 Dec 3;286(5446):1921-5
10583948
Theor Popul Biol. 2006 Sep;70(2):164-73
16723145
J Virol. 2000 Sep;74(18):8243-51
10954521
Arch Virol. 2000;145(7):1399-419
10963345
Vaccine. 2001 Aug 14;19(31):4479-86
11483274
J Clin Microbiol. 2002 Mar;40(3):1073-9
11880444
J Virol Methods. 2002 Apr;102(1-2):53-9
11879692
J Vet Diagn Invest. 2002 Mar;14(2):169-71
11939342
Can J Vet Res. 2002 Apr;66(2):117-21
11989733
Virus Res. 2002 May 10;85(2):199-210
12034486
Virus Res. 2002 Aug;87(2):173-9
12191781
Med Microbiol Immunol. 2002 Dec;191(3-4):133-8
12458347
Vaccine. 2003 May 1;21(16):1758-61
12686090
J Clin Microbiol. 2003 Jul;41(7):3198-205
12843064
Am J Vet Res. 2004 Mar;65(3):303-6
15027676
Virus Res. 2004 Jul;103(1-2):67-73
15163491
Virus Res. 2004 Jul;103(1-2):115-24
15163499
Science. 2004 Jul 16;305(5682):371-6
15218094
J Clin Microbiol. 1997 Oct;35(10):2623-7
9316919
J Virol. 1999 Oct;73(10):8851-6
10482643
Emerg Infect Dis. 2004 Dec;10(12):2156-60
15663853
J Clin Microbiol. 2000 Jun;38(6):2453-6
10835031