tetano
Editor, Senior Moderator
J Virol. 2010 Nov 3. [Epub ahead of print]
Genetic and phylogenetic analyses of Influenza A H1N1pdm in Buenos Aires, Argentina.
Barrero PR, Viegas M, Valinotto LE, Mistchenko AS.
Laboratorio de Virolog?a Hospital de Ni?os Dr. Ricardo Guti?rrez, Buenos Aires, Argentina. Gallo 1330 (1425) Buenos Aires, ARGENTINA; Consejo Nacional de Investigaciones Cient?ficas y T?cnicas (CONICET), Argentina; Comisi?n de Investigaciones Cient?ficas de la Provincia de Buenos Aires (CIC), Argentina.
Abstract
An influenza pandemic caused by swine-origin influenza virus A/H1N1 (H1N1pdm) spread worldwide in 2009, with 12,080 confirmed cases and 626 deaths in Argentina. A total of 330 H1N1pdm viruses were detected from May to August 2009 and phylogenetic and genetic analyses of 21 complete genome sequences from both mild and fatal cases were achieved with reference to concatenated whole genomes. In addition, the analysis of another 16 hemagglutinin (HA), neuraminidase (NA) and matrix (M) gene sequences of Argentinean isolates was performed. The timeline microevolution and resistance monitoring of an NA fragment from 228 samples throughout the 2009 pandemic peak was assessed by sequencing and pyrosequencing. We also assessed the viral growth kinetics for samples with replacements at genomic level or special clinical features. In this study we found that the Argentinean complete genome sequences clustered with globally-distributed clade seven sequences by Bayesian inference. The HA sequences were related to samples from the northern hemisphere autumn-winter from September-December 2009. The NA of Argentinean sequences belonged to the New York group. The N-4 fragment as well as the hierarchical clustering of samples showed that a consensus sequence prevailed in time but also that different variants, including five H275Y oseltamivir-resistant strains, arose from May to August 2009. Fatal and oseltamivir-resistant isolates had impaired growth and small plaque phenotype compared to oseltamivir-sensitive and consensus strains. Although these strains might not be fitted enough to spread in the entire population, molecular surveillance proved to be essential to monitor resistance and viral dynamics in our country.
PMID: 21047959 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/21047959
Genetic and phylogenetic analyses of Influenza A H1N1pdm in Buenos Aires, Argentina.
Barrero PR, Viegas M, Valinotto LE, Mistchenko AS.
Laboratorio de Virolog?a Hospital de Ni?os Dr. Ricardo Guti?rrez, Buenos Aires, Argentina. Gallo 1330 (1425) Buenos Aires, ARGENTINA; Consejo Nacional de Investigaciones Cient?ficas y T?cnicas (CONICET), Argentina; Comisi?n de Investigaciones Cient?ficas de la Provincia de Buenos Aires (CIC), Argentina.
Abstract
An influenza pandemic caused by swine-origin influenza virus A/H1N1 (H1N1pdm) spread worldwide in 2009, with 12,080 confirmed cases and 626 deaths in Argentina. A total of 330 H1N1pdm viruses were detected from May to August 2009 and phylogenetic and genetic analyses of 21 complete genome sequences from both mild and fatal cases were achieved with reference to concatenated whole genomes. In addition, the analysis of another 16 hemagglutinin (HA), neuraminidase (NA) and matrix (M) gene sequences of Argentinean isolates was performed. The timeline microevolution and resistance monitoring of an NA fragment from 228 samples throughout the 2009 pandemic peak was assessed by sequencing and pyrosequencing. We also assessed the viral growth kinetics for samples with replacements at genomic level or special clinical features. In this study we found that the Argentinean complete genome sequences clustered with globally-distributed clade seven sequences by Bayesian inference. The HA sequences were related to samples from the northern hemisphere autumn-winter from September-December 2009. The NA of Argentinean sequences belonged to the New York group. The N-4 fragment as well as the hierarchical clustering of samples showed that a consensus sequence prevailed in time but also that different variants, including five H275Y oseltamivir-resistant strains, arose from May to August 2009. Fatal and oseltamivir-resistant isolates had impaired growth and small plaque phenotype compared to oseltamivir-sensitive and consensus strains. Although these strains might not be fitted enough to spread in the entire population, molecular surveillance proved to be essential to monitor resistance and viral dynamics in our country.
PMID: 21047959 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/21047959