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Longitudinal Analysis of Influenza A(H5) Sero-Surveillance in Myanmar Ducks, 2006–2019

Year of publication 2021

Place of publication Basel, Switzerland ;

Pages 16 p.

Author Mon, H.H.; Hadrill, D.; Brioudes, A.; Mon, C.C.S.; Sims, L.; Win, H.H.; Thein, W.Z.; Mok, W.S.; Kyin, M.M.; Maw, M.T.; Win, Y.T.

Publisher MDPI ;

Product type Article

Edition 1

Synopsis (short abstract) Between 2006 and 2019, serological surveys in unvaccinated domestic ducks reared outdoors in Myanmar were performed, using a haemagglutination inhibition (HI) test, to confirm H5 avian influenza virus circulation and assess temporal and spatial distribution. Positive test results occurred every year that samples were collected. The annual proportion of positive farms ranged from 7.1% to 77.2%. The results revealed silent/sub-clinical influenza A (H5) virus circulation, even in years and States/Regions with no highly pathogenic avian influenza (HPAI) outbreaks reported. Further analysis of the 2018/19 results revealed considerable differences in seroconversion rates between four targeted States/Regions and between years, and showed seroconversion before and during the sampling period. By the end of the trial, a high proportion of farms were seronegative, leaving birds vulnerable to infection when sold. Positive results likely indicate infection with Gs/GD/96-lineage H5Nx HPAI viruses rather than other H5 subtype low-pathogenicity avian influenza viruses. The findings suggested persistent, but intermittent, circulation of Gs/GD/96-lineage H5Nx HPAI viruses in domestic ducks, despite the veterinary services’ outbreak detection and control efforts. The role of wild birds in transmission remains unclear but there is potential for spill-over in both directions. The findings of this study assist the national authorities in the design of appropriate, holistic avian influenza control programs.

This is an open access article published externally in Microorganisms (an Open Access Journal by MDPI), Special Issue "Ecology of Influenza A Viruses", published: 7 October 2021

Cite this content as:

Mon, H.H.; Hadrill, D.; Brioudes, A.; Mon, C.C.S.; Sims, L.; Win, H.H.; Thein, W.Z.; Mok, W.S.; Kyin, M.M.; Maw, M.T.; Win, Y.T. Longitudinal Analysis of Influenza A(H5) Sero-Surveillance in Myanmar Ducks, 2006–2019. Microorganisms 2021, 9, 2114. https://doi.org/10.3390/microorganisms9102114

Language English

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