nihao guest [ sign in / register ]
2022-8-19 21:26:53

Ripa RN, Sealy JE, Raghwani J, Das T, Barua H, Mas. Molecular epidemiology and pathogenicity of H5N1 and H9N2 avian influenza viruses in clinically affected chickens on farms in Bangladesh. Emerg Microbes Infect. 2021 Nov 10:1-408
submited by kickingbird at Nov, 12, 2021 10:19 AM from Emerg Microbes Infect. 2021 Nov 10:1-408

Avian influenza virus (AIV) subtypes H5N1 and H9N2 co-circulate in poultry in Bangladesh, causing significant bird morbidity and mortality. Despite their importance to the poultry value chain, the role of farms in spreading and maintaining AIV infections remains poorly understood in most disease-endemic settings. To address this crucial gap in our knowledge, we conducted a cross-sectional study between 2017 and 2019 in the Chattogram Division of Bangladesh in clinically affected and dead chickens in farms with suspected AIV infection. Viral prevalence of each subtype was approximately 10% among farms for which veterinary advice was sought, indicating a high level of virus circulation in chicken farms despite the low number of reported outbreaks. The level of co-circulation of both subtypes on farms was high, with our study suggesting that in the field, the co-circulation of H5N1 and H9N2 can modulate disease severity, which could facilitate an underestimated level of AIV transmission in the poultry value chain. Finally, using newly generated whole-genome sequences, we investigate the evolutionary history of a small subset of H5N1 and H9N2 viruses. Our analyses revealed that for both subtypes, the sampled viruses were genetically most closely related to other viruses isolated in Bangladesh and represented multiple independent incursions. However, due to lack of longitudinal surveillance in this region, it is difficult to ascertain whether these viruses emerged from endemic strains circulating in Bangladesh or from neighbouring countries. We also show that amino acids at putative antigenic residues underwent a distinct replacement during 2012 which coincides with the use of H5N1 vaccines.

See Also:

Latest articles in those days:

[Go Top]    [Close Window]

Related Pages:
Learn about the flu news, articles, events and more
Subscribe to the weekly F.I.C newsletter!


Site map  |   Contact us  |  Term of use  |  FAQs |  粤ICP备10094839号-1
Copyright ©www.flu.org.cn. 2004-2022. All Rights Reserved. Powered by FIC 4.0.1