pubmed.ncbi.nlm.nih.gov

Genetic and Antigenic Characteristics of Highly Pathogenic Avian Influenza A(H5N8) Viruses Circulating in Domestic Poultry in Egypt, 2017-2021 - PubMed

  • ️Sat Jan 01 2022

Genetic and Antigenic Characteristics of Highly Pathogenic Avian Influenza A(H5N8) Viruses Circulating in Domestic Poultry in Egypt, 2017-2021

Ahmed Kandeil et al. Microorganisms. 2022.

Abstract

In Egypt, the endemicity of avian influenza viruses is a serious concern. Since 2016, several outbreaks of H5N8 have been recorded among domestic poultry in various areas of the country. Active surveillance of domestic poultry across several governorates in Egypt from 2017 to 2021 detected at least six genotypes of Highly Pathogenic Avian Influenza (HPAI) H5N8 viruses with evidence of partial or complete annual replacement of dominant strains. Although all Egyptian H5N8 viruses had clade 2.3.4.4b hemagglutinin (HA) genes, the remaining viral gene segments were from multiple geographic origins, indicating that the H5N8 isolates resulted from multiple introductions. Mutations in the viral proteins associated with pathogenicity and antiviral drug resistance were detected. Some mutations in the HA resulted in antigenic drift. Heterogeneity in circulating H5N8 HPAI threatens poultry production and public health.

Keywords: Egypt; H5N8; highly pathogenic avian influenza; phylogenetic analysis; reassortment.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1

Phylogenetic tree of the nucleotide sequences of eight segments of H5N8 viruses. Isolates sequenced specifically for this study are indicated by circles with green, red, blue, yellow, and gray colors for 2017, 2018, 2019, 2020, and 2021, respectively. International related sequences of Egyptian H5N8 viruses were included and distinguished by text color. Phylogenetic analysis was performed using the neighbor-joining algorithm with the Kimura two-parameter model. The reliability of phylogenetic inference at each branch node was estimated by the bootstrap method with 1000 replications. Evolutionary analyses were conducted in MEGA X.

Figure 1
Figure 1

Phylogenetic tree of the nucleotide sequences of eight segments of H5N8 viruses. Isolates sequenced specifically for this study are indicated by circles with green, red, blue, yellow, and gray colors for 2017, 2018, 2019, 2020, and 2021, respectively. International related sequences of Egyptian H5N8 viruses were included and distinguished by text color. Phylogenetic analysis was performed using the neighbor-joining algorithm with the Kimura two-parameter model. The reliability of phylogenetic inference at each branch node was estimated by the bootstrap method with 1000 replications. Evolutionary analyses were conducted in MEGA X.

Figure 2
Figure 2

(A) Genetic constellation of six Egyptian HPAI H5N8 genotypes identified between 2017 and 2021 based on the genetic analysis of full-length genome sequences. (B) Pie chart showing the prevalence rate of different HPAI H5N8 genotypes. (C) Geographical distribution of different H5N8 genotypes.

Figure 3
Figure 3

Antigenic mapping based on the cross-reactivity of Egyptian H5 clade 2.3.4.4b viruses, with reference sera and 3D structure model of HA displayed in antigenic sites. Some strains drifted in cross-reactivity with reference sera due to mutations in antigenic sites A and B.

Similar articles

Cited by

References

    1. Pereira H.G., Tumova B., Law V.G. Avian influenza a viruses. Bull. World Health Organ. 1965;32:855–860. - PMC - PubMed
    1. Xu X., Subbarao K., Cox N.J., Guo Y. Genetic characterization of the pathogenic influenza a/goose/guangdong/1/96 (h5n1) virus: Similarity of its hemagglutinin gene to those of h5n1 viruses from the 1997 outbreaks in hong kong. Virology. 1999;261:15–19. doi: 10.1006/viro.1999.9820. - DOI - PubMed
    1. Dhingra M.S., Artois J., Dellicour S., Lemey P., Dauphin G., Von Dobschuetz S., Van Boeckel T.P., Castellan D.M., Morzaria S., Gilbert M. Geographical and historical patterns in the emergences of novel highly pathogenic avian influenza (hpai) h5 and h7 viruses in poultry. Front. Vet. Sci. 2018;5:84. doi: 10.3389/fvets.2018.00084. - DOI - PMC - PubMed
    1. El Shesheny R., Barman S., Feeroz M., Hasan M., Jones-Engel L., Franks J., Turner J., Seiler P., Walker D., Edwards K., et al. Genesis of influenza a(h5n8) viruses. Emerg. Infect. Dis. 2017;23:1368–1371. doi: 10.3201/eid2308.170143. - DOI - PMC - PubMed
    1. Kwon H.I., Kim E.H., Kim Y.I., Park S.J., Si Y.J., Lee I.W., Nguyen H.D., Yu K.M., Yu M.A., Jung J.H., et al. Comparison of the pathogenic potential of highly pathogenic avian influenza (hpai) h5n6, and h5n8 viruses isolated in south korea during the 2016–2017 winter season. Emerg. Microbes Infect. 2018;7:29. doi: 10.1038/s41426-018-0029-x. - DOI - PMC - PubMed

LinkOut - more resources