BACKGROUND: Examination of the evolutionary dynamics of complete influenza viral genomes reveals that other processes, in conjunction with antigenic drift, play important roles in viral evolution and selection, but there is little biological evidence to support these genomic data. Previous work demonstrated that after the A/Fujian/411/2002-like H3N2 influenza A epidemic during 2003-2004, a preexisting nondominant Fujian-like viral clade gained a small number of changes in genes encoding the viral polymerase complex, along with several changes in the antigenic regions of hemagglutinin, and in a genome-wide selective sweep, it replaced other co-circulating H3N2 clades. METHODS: Representative strains of these virus clades were evaluated in vitro and in vivo. RESULTS: The newly dominant 2004-2005 A/California/7/2004-like H3N2 clade, which featured 2 key amino acid changes in the polymerase PA segment, grew to higher titers in MDCK cells and ferret tissues and caused more-severe disease in ferrets. The polymerase complex of this virus demonstrated enhanced activity in vitro, correlating directly to the enhanced replicative fitness and virulence in vivo. CONCLUSION: These data suggest that influenza strains can be selected in humans through mutations that increase replicative fitness and virulence, in addition to the well-characterized antigenic changes in the surface glycoproteins.
BACKGROUND: Examination of the evolutionary dynamics of complete influenza viral genomes reveals that other processes, in conjunction with antigenic drift, play important roles in viral evolution and selection, but there is little biological evidence to support these genomic data. Previous work demonstrated that after the A/Fujian/411/2002-like H3N2influenza A epidemic during 2003-2004, a preexisting nondominant Fujian-like viral clade gained a small number of changes in genes encoding the viral polymerase complex, along with several changes in the antigenic regions of hemagglutinin, and in a genome-wide selective sweep, it replaced other co-circulating H3N2 clades. METHODS: Representative strains of these virus clades were evaluated in vitro and in vivo. RESULTS: The newly dominant 2004-2005 A/California/7/2004-like H3N2 clade, which featured 2 key amino acid changes in the polymerase PA segment, grew to higher titers in MDCK cells and ferret tissues and caused more-severe disease in ferrets. The polymerase complex of this virus demonstrated enhanced activity in vitro, correlating directly to the enhanced replicative fitness and virulence in vivo. CONCLUSION: These data suggest that influenza strains can be selected in humans through mutations that increase replicative fitness and virulence, in addition to the well-characterized antigenic changes in the surface glycoproteins.
Authors: Pedro Pechirra; Paulo Gonçalves; Ana Arraiolos; Anabela Coelho; Helena Rebelo-de-Andrade Journal: J Med Virol Date: 2008-09 Impact factor: 2.327
Authors: Colin A Russell; Terry C Jones; Ian G Barr; Nancy J Cox; Rebecca J Garten; Vicky Gregory; Ian D Gust; Alan W Hampson; Alan J Hay; Aeron C Hurt; Jan C de Jong; Anne Kelso; Alexander I Klimov; Tsutomu Kageyama; Naomi Komadina; Alan S Lapedes; Yi P Lin; Ana Mosterin; Masatsugu Obuchi; Takato Odagiri; Albert D M E Osterhaus; Guus F Rimmelzwaan; Michael W Shaw; Eugene Skepner; Klaus Stohr; Masato Tashiro; Ron A M Fouchier; Derek J Smith Journal: Science Date: 2008-04-18 Impact factor: 47.728
Authors: Elodie Ghedin; Naomi A Sengamalay; Martin Shumway; Jennifer Zaborsky; Tamara Feldblyum; Vik Subbu; David J Spiro; Jeff Sitz; Hean Koo; Pavel Bolotov; Dmitry Dernovoy; Tatiana Tatusova; Yiming Bao; Kirsten St George; Jill Taylor; David J Lipman; Claire M Fraser; Jeffery K Taubenberger; Steven L Salzberg Journal: Nature Date: 2005-10-05 Impact factor: 49.962
Authors: I G Barr; N Komadina; A C Hurt; P Iannello; C Tomasov; R Shaw; C Durrant; H Sjogren; A W Hampson Journal: J Med Virol Date: 2005-07 Impact factor: 2.327
Authors: Martha I Nelson; Lone Simonsen; Cecile Viboud; Mark A Miller; Jill Taylor; Kirsten St George; Sara B Griesemer; Elodie Ghedin; Elodie Ghedi; Naomi A Sengamalay; David J Spiro; Igor Volkov; Bryan T Grenfell; David J Lipman; Jeffery K Taubenberger; Edward C Holmes Journal: PLoS Pathog Date: 2006-12 Impact factor: 6.823
Authors: Silvana Carr; Natalia A Ilyushina; John Franks; Elisabeth E Adderson; Miguela Caniza; Elena A Govorkova; Robert G Webster Journal: Pediatr Infect Dis J Date: 2011-04 Impact factor: 2.129
Authors: J Brian Kimble; Erin Sorrell; Hongxia Shao; Philip L Martin; Daniel Roberto Perez Journal: Proc Natl Acad Sci U S A Date: 2011-07-05 Impact factor: 11.205
Authors: Peng Wu; Edward Goldstein; Lai Ming Ho; Lin Yang; Hiroshi Nishiura; Joseph T Wu; Dennis K M Ip; Shuk-Kwan Chuang; Thomas Tsang; Benjamin J Cowling Journal: J Infect Dis Date: 2012-10-08 Impact factor: 5.226