Genomic diversity of oseltamivir-resistant influenza virus A (H1N1), Luxembourg, 2007-08.
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ABSTRACT:
SUBMITTER: Gerloff NA
PROVIDER: S-EPMC2819849 | biostudies-literature | 2009 Sep
REPOSITORIES: biostudies-literature
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Genomic diversity of oseltamivir-resistant influenza virus A (H1N1), Luxembourg, 2007-08.
Gerloff Nancy A NA Kremer Jacques R JR Mossong Jöel J Opp Matthias M Muller Claude P CP
Emerging infectious diseases 20090901 9
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Project description:In Europe, the 2007-08 winter season was dominated by influenza virus A (H1N1) circulation through week 7, followed by influenza B virus from week 8 onward. Oseltamivir-resistant influenza viruses A (H1N1) (ORVs) with H275Y mutation in the neuraminidase emerged independently of drug use. By country, the proportion of ORVs ranged from 0% to 68%, with the highest proportion in Norway. The average weighted prevalence of ORVs across Europe increased gradually over time, from near 0 in week 40 of 2007 to 56% in week 19 of 2008 (mean 20%). Neuraminidase genes of ORVs possessing the H275Y substitution formed a homogeneous subgroup closely related to, but distinguishable from, those of oseltamivir-sensitive influenza viruses A (H1N1). Minor variants of ORVs emerged independently, indicating multiclonal ORVs. Overall, the clinical effect of ORVs in Europe, measured by influenza-like illness or acute respiratory infection, was unremarkable and consistent with normal seasonal activity.
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