New Reassortant Clade 2.3.4.4b Avian Influenza A(H5N6) Virus in Wild Birds, South Korea, 2017-18.

Jung-Hoon Kwon,Sun-hak Lee,Jei-Hyun Jeong,Tseren-Ochir Erdene-Ochir,Jin-Yong Noh,David E. Swayne,Chang-Seon Song,Sol Jeong,Yu-jin Kim,Dong-Hun Lee

doi:10.3201/eid2410.180461

Abstract

We isolated new reassortant avian influenza A(H5N6) viruses from feces of wild waterfowl in South Korea during 2017–18. Phylogenetic analysis suggested that reassortment occurred between clade 2.3.4.4b H5N8 and Eurasian low pathogenicity avian influenza viruses circulating in wild birds. Dissemination to South Korea during the 2017 fall migratory season followed.

Highlights

Clade 2.3.4.4 H5 highly pathogenic avian influenza viruses (HPAIVs) have evolved by reassortment with different neuraminidase (NA) and internal genes of prevailing low pathogenicity avian influenza viruses (LPAIVs) and other HPAIVs to generate new genotypes and further evolved into genetic subgroups A–D since 2014 [1]
During December 2017–January 2018 in South Korea, we isolated 6 H5N6 HPAIVs from 231 fecal samples of wild birds collected from the banks of the Cheongmi-cheon River (37°06′56.9′′N, 127°25′18.3′′E) and 34 from 222 fecal samples collected from the banks of the Gokgyo-cheon River (36°45′12.3′N, 127°07′12.7′E)
We identified avian influenza virus–positive fecal samples from 38 Mandarin ducks and 2 mallards, based on DNA barcoding technique [10]

Summary

Introduction

Clade 2.3.4.4 H5 highly pathogenic avian influenza viruses (HPAIVs) have evolved by reassortment with different neuraminidase (NA) and internal genes of prevailing low pathogenicity avian influenza viruses (LPAIVs) and other HPAIVs to generate new genotypes and further evolved into genetic subgroups A–D since 2014 [1]. Subgroup B H5N6 viruses were isolated from birds in Greece during February 2017 and England, Germany, the Netherlands, Japan, and Taiwan during winter 2017–18 [7,8]. During December 2017–January 2018 in South Korea, we isolated 6 H5N6 HPAIVs from 231 fecal samples of wild birds collected from the banks of the Cheongmi-cheon River (37°06′56.9′′N, 127°25′18.3′′E) and 34 from 222 fecal samples collected from the banks of the Gokgyo-cheon River (36°45′12.3′N, 127°07′12.7′E) (online Technical Appendix 1, https://wwwnc.cdc.gov/EID/article/24/10/180461-Techapp1.pdf).

Results

Conclusion