Identification of Two novel reassortant avian influenza a (H5N6) viruses in whooper swans in Korea, 2016.
On November 20, 2016 two novel strains of H5N6 highly pathogenic avian influenza virus (HPAIVs) were isolated from three whooper swans (Cygnus cygnus) at Gangjin Bay in South Jeolla province, South Korea. Identification of HPAIVs in wild birds is significant as there is a potential risk of transmission of these viruses to poultry and humans.



Phylogenetic analysis revealed that Gangjin H5N6 viruses classified into Asian H5 clade 2.3.4.4 lineage and were distinguishable from H5N8 and H5N1 HPAIVs previously isolated in Korea. With the exception of the polymerase acidic (PA) gene, the viruses were most closely related to A/duck/Guangdong/01.01SZSGXJK005-Y/2016 (H5N6) (98.90 ~ 99.74%). The PA genes of the two novel Gangjin H5N6 viruses were most closely related to AIV isolates previously characterized from Korea, A/hooded crane/Korea/1176/2016 (H1N1) (99.16%) and A/environment/Korea/W133/2006 (H7N7) (98.65%). The lack of more recent viruses to A/environment/Korea/W133/2006 (H7N7) indicates the need for analysis of recent wild bird AIVs isolated in Korea because they might provide further clues as to the origin of these novel reassortant H5N6 viruses.



Although research on the origins and epidemiology of these infections is ongoing, the most likely route of infection for the whooper swans was through direct or indirect contact with reassortant viruses shed by migratory wild birds in Korea. As H5N6 HPAIVs can potentially be transmitted to poultry and humans, continuous monitoring of AIVs among wild birds will help to mitigate this risk.
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea. czar21@korea.kr.
Jipseol
0000-0002-7149-4090
J
Jeong
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Chanjin
C
Woo
U.S. Geological Survey, National Wildlife Health Center, Madison, WI, USA.
Hon S
HS
Ip
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Injung
I
An
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Youngsik
Y
Kim
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Kwanghee
K
Lee
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Seong-Deok
SD
Jo
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Kidong
K
Son
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Saemi
S
Lee
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Jae-Ku
JK
Oem
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Seung-Jun
SJ
Wang
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Yongkwan
Y
Kim
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea.
Jeonghwa
J
Shin
U.S. Geological Survey, National Wildlife Health Center, Madison, WI, USA.
Jonathan
J
Sleeman
Environmental Health Research Department, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, Republic of Korea. purify@korea.kr.
Weonhwa
W
Jheong
D000818:Animals; D046090:Anseriformes / Q000821:virology*; D016000:Cluster Analysis; D009980:Influenza A virus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D005585:Influenza in Birds / Q000821:virology*; D010802:Phylogeny; D016865:Reassortant Viruses / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D056910:Republic of Korea
H5N6; Highly pathogenic avian influenza viruses; Korea; Whooper swans