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

• Main Authors: Camila Marx, Tatiana Schaffer Gregianini, Fernanda Kieling Moreira Lehmann, Vagner Ricardo Lunge, Silvia de Carli, Bibiana Paula Dambros, Gabriela Luchiari Tumioto, Claudete Seadi, Andre Salvador Kazantzi Fonseca, Nilo Ikuta
• Format: Article
• Language: English
• Published: Instituto Oswaldo Cruz, Ministério da Saúde 2013-05-01
• Series: Memórias do Instituto Oswaldo Cruz.
• Subjects: influenza A(H1N1)pmd09; resistance; oseltamivir
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762013000300392&lng=en&tlng=en

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.