title: Novel Reassortant H5N6 Influenza A Virus from the Lao People's Democratic Republic Is Highly Pathogenic in Chickens.
abstract: Avian influenza viruses of H5 subtype can cause highly pathogenic disease in poultry. In March 2014, a new reassortant H5N6 subtype highly pathogenic avian influenza virus emerged in Lao People's Democratic Republic. We have assessed the pathogenicity, pathobiology and immunological responses associated with this virus in chickens. Infection caused moderate to advanced disease in 6 of 6 chickens within 48 h of mucosal inoculation. High virus titers were observed in blood and tissues (kidney, spleen, liver, duodenum, heart, brain and lung) taken at euthanasia. Viral antigen was detected in endothelium, neurons, myocardium, lymphoid tissues and other cell types. Pro-inflammatory cytokines were elevated compared to non-infected birds. Our study confirmed that this new H5N6 reassortant is highly pathogenic, causing disease in chickens similar to that of Asian H5N1 viruses, and demonstrated the ability of such clade 2.3.4-origin H5 viruses to reassort with non-N1 subtype viruses while maintaining a fit and infectious phenotype. Recent detection of influenza H5N6 poultry infections in Lao PDR, China and Viet Nam, as well as six fatal human infections in China, demonstrate that these emergent highly pathogenic H5N6 viruses may be widely established in several countries and represent an emerging threat to poultry and human populations.
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Butler
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Cameron R
authors.initials: CR
authors.lastname: Stewart
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Layton
authors.affiliation: National Animal Health Laboratory, Vientiane, Lao People's Democratic Republic.
authors.forename: Phouvong
authors.initials: P
authors.lastname: Phommachanh
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Harper
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Jean
authors.initials: J
authors.lastname: Payne
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Evans
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Stacey
authors.initials: S
authors.lastname: Valdeter
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Som
authors.initials: S
authors.lastname: Walker
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Gemma
authors.initials: G
authors.lastname: Harvey
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Songhua
authors.initials: S
authors.lastname: Shan
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Bruce
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Christina L
authors.initials: CL
authors.lastname: Rootes
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Tamara J
authors.initials: TJ
authors.lastname: Gough
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Andreas
authors.initials: A
authors.lastname: Rohringer
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Grantley R
authors.initials: GR
authors.lastname: Peck
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Fardy
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Karpala
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Dayna
authors.initials: D
authors.lastname: Johnson
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Jianning
authors.initials: J
authors.lastname: Wang
authors.affiliation: National Animal Health Laboratory, Vientiane, Lao People's Democratic Republic.
authors.forename: Bounlom
authors.initials: B
authors.lastname: Douangngeun
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Christopher
authors.initials: C
authors.lastname: Morrissy
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Frank Y K
authors.initials: FY
authors.lastname: Wong
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Andrew G D
authors.initials: AG
authors.lastname: Bean
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Bingham
authors.affiliation: CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: David T
authors.initials: DT
authors.lastname: Williams
mesh_terms: D000818:Animals; D002645:Chickens / Q000382:microbiology*; D004285:Dogs; D009980:Influenza A virus / Q000302:isolation & purification / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000821:virology*; D007812:Laos; D061985:Madin Darby Canine Kidney Cells; D016865:Reassortant Viruses / Q000302:isolation & purification / Q000472:pathogenicity*; D019562:Viral Load