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Oseltamivir-resistant influenza A(H1N1)pdm09 virus in southern Brazil.

ABSTRACT: The neuraminidase (NA) genes of A(H1N1)pdm09 influenza virus isolates from 306 infected patients were analysed. The circulation of oseltamivir-resistant viruses in Brazil has not been reported previously. Clinical samples were collected in the state of Rio Grande do Sul (RS) from 2009-2011 and two NA inhibitor-resistant mutants were identified, one in 2009 (H275Y) and the other in 2011 (S247N). This study revealed a low prevalence of resistant viruses (0.8%) with no spread of the resistant mutants throughout RS.

SUBMITTER: Marx C

PROVIDER: S-EPMC4005575 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Oseltamivir-resistant influenza A(H1N1)pdm09 virus in southern Brazil.

Marx Camila C Gregianini Tatiana Schäffer TS Lehmann Fernanda Kieling Moreira FK Lunge Vagner Ricardo VR Carli Silvia de Sd Dambrós Bibiana Paula BP Tumioto Gabriela Luchiari GL Seadi Claudete C Fonseca André Salvador Kazantzi AS Ikuta Nilo N

Memorias do Instituto Oswaldo Cruz 20130501 3

The neuraminidase (NA) genes of A(H1N1)pdm09 influenza virus isolates from 306 infected patients were analysed. The circulation of oseltamivir-resistant viruses in Brazil has not been reported previously. Clinical samples were collected in the state of Rio Grande do Sul (RS) from 2009-2011 and two NA inhibitor-resistant mutants were identified, one in 2009 (H275Y) and the other in 2011 (S247N). This study revealed a low prevalence of resistant viruses (0.8%) with no spread of the resistant mutan ...[more]

PMID: 23778667

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Oseltamivir-resistant influenza A(H1N1)pdm09 viruses, United States, 2013-14.

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