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Ahead of Print -Novel Reassortant Influenza A(H5N8) Viruses among Inoculated Domestic and Wild Ducks, South Korea, 2014 - Volume 21, Number 2—February 2015 - Emerging Infectious Disease journal - CDC

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Ahead of Print -Novel Reassortant Influenza A(H5N8) Viruses among Inoculated Domestic and Wild Ducks, South Korea, 2014 - Volume 21, Number 2—February 2015 - Emerging Infectious Disease journal - CDC

CDC. Centers for Disease Control and Prevention. CDC 24/7: Saving Lives. Protecting People.

Volume 21, Number 2—February 2015


Novel Reassortant Influenza A(H5N8) Viruses among Inoculated Domestic and Wild Ducks, South Korea, 2014

Hyun-Mi Kang, Eun-Kyoung Lee, Byung-Min Song, Jipseol Jeong, Jun-Gu Choi, Joojin Jeong, Oun-Kyong Moon, Hachung Yoon, Youngmi Cho, Young-Myong Kang, Hee-Soo Lee, and Youn-Jeong LeeComments to Author 
Author affiliations: Animal and Plant Quarantine Agency, Anyang, South Korea


An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%–20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of the spread of this virus among wild birds and poultry, especially domestic ducks.
Wild birds in orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shore birds) are the natural reservoirs of avian influenza viruses (1,2). In wild aquatic birds, low pathogenicity avian influenza viruses are in a state of evolutionary equilibrium, and infected hosts usually show no signs of disease. However, a Qinghai-like H5N1 virus caused an outbreak in migratory waterfowl during 2005 before spreading from Asia to Europe and Africa (3,4). The outbreak gave rise to concerns that infections of wild birds with the highly pathogenic avian influenza (HPAI) virus subtype H5N1, which causes mild or no clinical signs in these birds, could result in transmission of the virus over long distances (5,6).
As was the case in other wild birds, HPAI H5N1viruses were not known to be pathogenic in domestic ducks before 2002 (79), but since then, HPAI H5N1 viruses that are pathogenic in ducks have been isolated in many countries (3,5,10,11). In South Korea, 4 outbreaks of HPAI H5N1have occurred among poultry (mainly chickens and domestic ducks) and wild birds. Before 2010, H5N1 HPAI viruses among birds were detected mostly in poultry (chickens, domestic ducks, and quail), with the single exception of 1 magpie in 2004. By contrast, during 2010–2011, many cases occurred in various wild birds such as the Eurasian eagle owl, mandarin duck, Baikal teal duck, mallard duck, whooper swan, spot-billed duck, sparrow hawk, common kestrel, and white-fronted goose, as well as in poultry. Although all viruses in these outbreaks were highly pathogenic in chickens, the pathogenicity of these viruses varied among domestic ducks; the pathogenicity was 0%–25% during 2003–2004 (clade 2.5, H5N1), 0% during 2006–2007 (clade 2.2, H5N1), 50%–100% during 2008 (clade, H5N1), and 50%–100% during 2010–2011 (clade, H5N1) (5,1215).
Outbreaks of HPAI H5N8 infection in poultry were first reported in ducks and turkeys in Ireland in 1983. In 2010, outbreaks of infection with the HPAI H5N8 virus derived from the Goose/Guangdong/1/1996 (Gs/GD) lineage were first reported in duck farms in Jiangsu, China (16). Early in 2014, an outbreak of HPAI caused by a novel reassortant H5N8 virus occurred in Korea. The virus belonged to clade and comprised 2 distinct genotypes (17). It has been suggested that viruses belonging to the major genotypes Buan2 and Donglim3 might be reassortants containing the polymerase basic protein 2, hemagglutinin (HA), nucleoprotein, and neuraminidase (NA) genes from viruses in the outbreak in China during 2010 (A/duck/Jiangsu/k1203/2013 (H5N8) (17). The HPAI H5N8 viruses were isolated from both wild birds and poultry. They were found in captured, apparently healthy, migratory wild birds and in dead birds, including mallards (both alive and dead), and in domestic chickens, geese, and ducks; the outbreak positive rate on duck farms was >70% (13).
There have been no previous reports about the pathogenicity of novel reassortant H5N8 isolates in wild birds and domestic ducks. Therefore, the aim of this study was to evaluate the pathogenesis in and mode of transmission of a novel reassortant H5N8 virus among mallard and domestic ducks, which are the poultry populations primarily affected by these viruses in South Korea.


This work was supported by grants from the Animal, Plant and Quarantine Agency (B–1541767–2013–15–01) and from the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (313016031SB010), Republic of Korea.
Dr. Kang is a microbiologist at the Animal and Plant Quarantine Agency, South Korea. Her research interests are focused on surveillance, genetics, and pathogenesis of avian influenza.


  1. Fouchier RAMunster VWallensten ABestebroer TMHerfst SSimth DCharacterization of a novel influenza A virus hemagglutinin subtype (H16) obtained from black-headed gulls. J Virol2005;79:281422DOIPubMed
  2. Webster RGBean WJGorman OTChambers YKawaoka YEvolution and ecology of influenza A viruses. Microbiol Rev1992;56:15279.PubMed
  3. Chen HDeng GLi ZTian GLi YJiao PThe evolution of H5N1 influenza viruses in ducks in southern China. Proc Natl Acad Sci U S A.2004;101:104527DOIPubMed
  4. Liu JXiao HLei FZhu QQin KZhang XWHighly pathogenic H5N1 influenza virus infection in migratory birds. Science2005;309:1206.DOIPubMed
  5. Kim HRKim BSBae YCMoon OKOem JKKang HMH5N1 subtype highly pathogenic avian influenza virus isolated from healthy mallard captured in South Korea. Vet Microbiol2011;151:3869DOIPubMed
  6. Sakoda YSugar SBatchluun DErdene-Ochir TOOkamatsu MIsoda NCharacterization of H5N1 highly pathogenic avian influenza virus strains isolated from migratory waterfowl in Mongolia on the way back from the southern Asia to their northern territory. Virology2010;406:8894.DOIPubMed
  7. Alexander DJParsons GManvell RGExperimental assessment of the pathogenicity of eight avian influenza A viruses of H5 subtype for chickens, turkeys, ducks and quail. Avian Pathol1986;15:64762DOIPubMed
  8. Perkins LESwayne DEPathogenicity of a Hong Kong-origin H5N1 highly pathogenic avian influenza virus for emus, geese, ducks, and pigeons.Avian Dis2002;46:5363DOIPubMed
  9. Webster RGGuan YPeiris MWalker DKrauss SZhou NNCharacterization of H5N1 influenza viruses that continue to circulate in geese in southeastern China. J Virol2002;76:11826DOIPubMed
  10. Kang HMChoi JGKim KIKim BSBatchuluun DErdene-Ochir TOPathogenicity in domestic ducks and mice of highly pathogenic H5N1 clade influenza viruses recently circulating in Eastern Asia. Vet Microbiol2013;167:32733DOIPubMed
  11. Sturm-Ramirez KMEllis TBousfield BBissett LDyrting KRehg JEReemerging H5N1 influenza viruses in Hong Kong in 2002 are highly pathogenic to ducks. J Virol2004;78:4892901DOIPubMed
  12. Choi JGKang HMJeon WJChoi KSKim KISong BMCharacterization of clade H5N1 highly pathogenic avian influenza viruses isolated from wild birds (mandarin duck and Eurasian eagle owl) in 2010 in Korea. Viruses2013;5:115374DOIPubMed
  13. Jeong JKang HMLee EKSong BMKwon YKKim HRHighly pathogenic avian influenza virus (H5N8) in domestic poultry and its relationship with migratory birds in South Korea during 2014. Vet Microbiol2014;173:24957DOIPubMed
  14. Jeong OMKim MCKim MJKang HMKim HRKim YJExperimental infection of chickens, ducks and quails with the highly pathogenic H5N1 avian influenza virus. J Vet Sci2009;10:5360DOIPubMed
  15. Lee CWSuarez DLTumpey TMSung HWKwon YKLee YJCharacterization of highly pathogenic H5N1 avian influenza A viruses isolated from South Korea. J Virol2005;79:3692702DOIPubMed
  16. Wu HPeng XXu LJin CCheng LLu XNovel Reassortant Influenza A(H5N8) Viruses in Domestic Ducks, Eastern China. Emerg Infect Dis.2014;20:13158DOIPubMed
  17. Lee YJKang HMLee EKSong BMJeong JSKwon YKNovel reassortant influenza A(H5N8) viruses, South Korea, 2014. Emerg Infect Dis.2014;20:10879DOIPubMed
  18. Reed LJMuench HA simple method for estimating fifty per cent endpoints. Am J Hyg1938;27:4937.
  19. World Health Organization. WHO manual on animal influenza diagnosis and surveillance.http://www.who.int/csr/resources/publications/influenza/en/whocdscsrncs20025rev.pdf
  20. Brown JDStallknecht DEBeck JRSuarez DLSwayne DESusceptibility of North American ducks and gulls to H5N1 highly pathogenic avian influenza viruses. Emerg Infect Dis2006;12:166370DOIPubMed
  21. World Health Organization/World Organisation for Animal Health/Food and Agriculture Organization H5N1 Evolution Working Group. Toward a unified nomenclature system for highly pathogenic avian influenza virus (H5N1) [conference summary]Emerg Infect Dis2008;14:••• PubMed.
  22. Gu MLiu WCao YPeng DWang XWan HNovel reassortant highly pathogenic avian influenza (H5N5) viruses in domestic ducks, China. Emerg Infect Dis2011;17:10603DOIPubMed
  23. Zhao KGu MZhong LDuan ZZhang YZhu YCharacterization of three H5N5 and one H5N8 highly pathogenic avian influenza viruses in China.Vet Microbiol2013;163:3517DOIPubMed
  24. Liu CGLiu MLiu FLv RLiu DFQu LDEmerging multiple reassortant H5N5 avian influenza viruses in ducks, China, 2008. Vet Microbiol.2013;167:296306DOIPubMed
  25. Lee YJKang HMChoi JGJeong OMKim MCPaek MRHigher virulence of the Korean clade highly pathogenic avian influenza A (H5N1) virus isolated in 2008 in young duckling. Journal of Zoonoses. 2011;2:217.
  26. Tang YWu PPeng DWang XWan HZhang PCharacterization of duck H5N1 influenza viruses with differing pathogenicity in mallard (Anas platyrhynchos) ducks. Avian Pathol2009;38:45767DOIPubMed
  27. Keawcharoen Jvan Riel Dvan Amerongen GBestebroer TBeyer WEvan Lavieren RWild ducks as long-distance vectors of highly pathogenic avian influenza virus (H5N1). Emerg Infect Dis2008;14:6007DOIPubMed
  28. Hulse-Post DJSturm-Ramirez KMHumberdm JSeilerm PGovorkova EAKrauss SRole of domestic ducks in the propagation and biological evolution of highly pathogenic H5N1 influenza viruses in Asia. Proc Natl Acad Sci U S A2005;102:106827DOIPubMed
  29. Pantin-Jackwood MJSwayne DEPathobiology of Asian highly pathogenic avian influenza H5N1 virus infections in ducks. Avian Dis.2007;51:2509DOIPubMed
  30. Sturm-Ramirez KMHulse-Post DJGovorkova EAHumberd JSeiler PPuthavathana PAre ducks contributing to the endemicity of highly pathogenic H5N1 influenza virus in Asia? J Virol2005;79:1126979DOIPubMed



Suggested citation for this article: Kang HM, Lee EK, Song BM, Jeong J, Choi JG, et al. Novel reassortant influenza A(H5N8) viruses among domestic and wild ducks, South Korea, 2014. Emerg Infect Dis. 2015 Feb [date cited]. http://dx.doi.org/10.3201/eid2102.141268
DOI: 10.3201/eid2102.141268

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