RESUMO
In China H3N2 and H1N1 swine influenza viruses have been circulating for many years. In January 2010, before swine were infected with foot and mouth disease in Guangdong, some pigs have shown flu-like symptoms: cough, sneeze, runny nose and fever. We collected the nasopharyngeal swab of all sick pigs as much as possible. One subtype H1N2 influenza viruses were isolated from the pig population. The complete genome of one isolate, designated A/swine/Guangdong/1/2010(H1N2), was sequenced and compared with sequences available in GenBank. The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. HA, NP, M and NS were shown to be closely to swine origin. PB2 and PA were close to avian origin, but NA and PB1were close to human origin. It is a result of a multiple reassortment event. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV) surveillance, especially before the emergence of highly pathogenic FMDs in pigs in Guangdong.
Assuntos
Genoma Viral , Vírus da Influenza A Subtipo H1N2/classificação , Vírus da Influenza A Subtipo H1N2/genética , Infecções por Orthomyxoviridae/veterinária , RNA Viral/genética , Doenças dos Suínos/virologia , Animais , China , Análise por Conglomerados , Evolução Molecular , Genótipo , Vírus da Influenza A Subtipo H1N2/isolamento & purificação , Dados de Sequência Molecular , Nasofaringe/virologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/patologia , Proteínas Virais/genéticaRESUMO
Two swine influenza (SI) H1N1 virus was isolated from a pig during a severe outbreak of respiratory disease in south China. The two H1N1 influenza viruses were classical SI virus. A/swine/Guangdong/L6/09 is classical SI virus of recent years, which is of the main SI virus in China. Howere, A/swine/Guangdong/L3/09 was closet to A/swine/Iowa/1931, which was the first isolated SI virus and had demonstrated significant pathogenicity in animal models. The results of phylogenetic analysis of A/swine/Guangdong/L3/09 showed a close relationship with the 1918 pandemic virus. The results suggested that the previous SI virus appeared again. Whether, it brought a new pandemic to pigs deserves more attention.
