background and objectives: a number of different subtypes of avian influenza (ai) viruses have emerged in humans includingh5n1, h7n2, h7n7 and h9n2. these influenza viruses are excreted in the infected birds and in their respiratory secretions.the aim of this study was to investigate seropositivity against h9n2 and h7n7 viruses among poultry and slaughterhouse workers with occupational risk of ...

Nigeria has had multiple incursions of highly pathogenic avian influenza A (HPAI) H5N1 virus into its poultry population since 2006. This study aimed to determine if Nigerians exposed to poultry had evidence of avian influenza virus transmission to man. Between 2008 and 2010, 316 adult farmers and open market workers and 54 age-group matched, non-animal exposed controls were enrolled in a prosp...

influenza a viruses possesses two virion surface glycoproteins including haemagglutinin (ha) and neuraminidase (na). the na plays an important role in viral replication and promotes virus release from infected cells and facilitates virus spread throughout the body. to find out any genomic changes that might be occurred on na gene of avian influenza circulating viruses, we have genetically analy...

conclusions taken together, these data reveal that cellular protease of chicken liver cells allows the replication of high yields of h9n2 virus in the absence of trypsin and also cell death in the infected cells is due to necrosis. results the degree of viability was significantly reduced in infected hepatoma cells. observations of caspase activation and cell dna laddering in infected cells wer...

background and aims: hemagglutinin (ha) protein of avian influenza (ai) plays an essential role in the virus pathogenicity. ai h9n2 subtype causes significant economic loss in broiler and layer in poultry farms in iran. ai viruses have a great involvement in evolutionary changes at nucleotide and amino acid levels and vaccines could induce faster rates of such changes. up-dated understanding of...

Influenza viruses of avian origin continue to pose pandemic threats to human health. Some of the H5N1 and H9N2 virus subtypes induce markedly elevated cytokine levels when compared with the seasonal H1N1 virus. We previously showed that H5N1/97 hyperinduces tumor necrosis factor (TNF)-alpha through p38 mitogen activated protein kinase (MAPK). However, the detailed mechanisms of p38MAPK activati...

UNLABELLED The novel H7N9 avian influenza virus (AIV) was demonstrated to cause severe human respiratory infections in China. Here, we examined poultry specimens from live bird markets linked to human H7N9 infection in Hangzhou, China. Metagenomic sequencing revealed mixed subtypes (H5, H7, H9, N1, N2, and N9). Subsequently, AIV subtypes H5N9, H7N9, and H9N2 were isolated. Evolutionary analysis...

The H9N2 subtype influenza virus (IV) is a remarkable member of the influenza A viruses because it can infect not only chickens, ducks and pigs, but also humans. Pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. To further unders...

In 1997, 18 cases of influenza in Hong Kong (bird flu) caused by a novel H5N1 (chicken) virus resulted in the deaths of six individuals and once again raised the specter of a potentially devastating influenza pandemic. Slaughter of the poultry in the live bird markets removed the source of infection and no further human cases of H5N1 infection have occurred. In March 1999, however, a new pandem...

backgrounds and objectives: classified as low pathogenic avian influenza (lpai) viruses, the h9n2 subtype causes severe respiratory disease in poultry farms and occasional respiratory disease in humans. in this study, the neuraminidase (na) gene of three avian influenza (ai) h9n2 strains isolated from poultry farms in iran during 2010-11, as well as other reported iranian h9n2 isolates, were ge...