#Genetics and #pathogenicity of #H5N6 highly pathogenic #avian #influenza viruses isolated from #wildbirds and a #chicken in #Japan during winter 2017-2018 (Virology, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Virology. 2019 May 2;533:1-11. doi: 10.1016/j.virol.2019.04.011. [Epub ahead of print]

Genetics and pathogenicity of H5N6 highly pathogenic avian influenza viruses isolated from wild birds and a chicken in Japan during winter 2017-2018.

Mine J1, Uchida Y1, Nakayama M1, Tanikawa T1, Tsunekuni R1, Sharshov K2, Takemae N1, Sobolev I2, Shestpalov A2, Saito T3.

Author information: 1 Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan; Thailand-Japan Zoonotic Diseases Collaboration Center, Kasetklang, Chatuchak, Bangkok, 10900, Thailand. 2 Federal Research Center of Fundamental and Translational Medicine, Novosibirsk, Russia. 3 Division of Transboundary Animal Disease, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan; Thailand-Japan Zoonotic Diseases Collaboration Center, Kasetklang, Chatuchak, Bangkok, 10900, Thailand; United Graduate School of Veterinary Sciences, Gifu University, 1-1, Yanagito, Gifu, Gifu, 501-1112, Japan. Electronic address: taksaito@affrc.go.jp.



An H5N6 highly pathogenic avian influenza virus (HPAIV) outbreak occurred in poultry in Japan during January 2018, and H5N6 HPAIVs killed several wild birds in 3 prefectures during Winter 2017-2018. Time-measured phylogenetic analyses demonstrated that the Hemagglutinin (HA) and internal genes of these isolates were genetically similar to clade H5N8 HPAIVs in Europe during Winter 2016-2017, and Neuraminidase (NA) genes of the poultry and wild bird isolates were gained through distinct reassortments with AIVs that were estimated to have circulated possibly in Siberia during Summer 2017 and Summer 2016, respectively. Lethal infectious dose to chickens was similar between the poultry and wild-bird isolates. H5N6 HPAIVs during Winter 2017-2018 in Japan had higher 50% chicken lethal doses and lower transmission efficiency than the H5Nx HPAIVs that caused previous outbreaks in Japan, thus explaining in part why cases during the 2017-2018 outbreak were sporadic.

Copyright © 2019 Elsevier Inc. All rights reserved.

KEYWORDS: Animal RNA virus; H5N6 highly pathogenic avian influenza; Pathogenicity; Phylogeny

PMID: 31071540 DOI: 10.1016/j.virol.2019.04.011

Keywords: Avian Influenza; H5N6; H5N8; Wild Birds; Poultry; Japan.



Loss of #fitness in #mallards of #Mexican #H7N3 highly pathogenic #avian #influenza virus after circulating in #chickens (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Loss of fitness in mallards of Mexican H7N3 highly pathogenic avian influenza virus after circulating in chickens

Sung-Su Youk, Dong-Hun Lee, Christina M. Leyson, Diane Smith, Miria Ferreira Criado, Eric DeJesus, David E. Swayne, Mary J. Pantin-Jackwood

DOI: 10.1128/JVI.00543-19



Outbreaks of highly pathogenic avian influenza (HPAI) virus subtype H7N3 have been occurring in commercial chickens in Mexico since its first introduction in 2012. In order to determine changes in virus pathogenicity and adaptation in avian species, three H7N3 HPAI viruses from 2012, 2015, and 2016 were evaluated in chickens and mallards. All three viruses caused high mortality in chickens when given at medium to high doses and replicated similarly. No mortality or clinical signs and similar infectivity were observed in mallards inoculated with the 2012 and 2016 viruses. However, the 2012 H7N3 HPAI virus replicated well in mallards and transmitted to contacts, whereas the 2016 virus replicated poorly and did not transmit to contacts, which indicates that the 2016 virus is less adapted to mallards. In vitro, the 2016 virus grew slower and to lower titers than the 2012 virus in duck fibroblast cells. Full genome sequencing showed 115 amino acid differences between the 2012 and the 2016 virus, with some of these changes previously associated with changes in replication in avian species including HA A125T, NP M105V and NP S377N. In conclusion, as the Mexican H7N3 HPAI virus has passaged through large populations of chickens in a span of several years, it has retained its high pathogenicity for chickens but has decreased in fitness in mallards which could limit the potential spread of this HPAI virus by waterfowl.



Not much is known about changes in host adaptation of avian influenza (AI) viruses in birds after long-term circulation in chickens or other terrestrial poultry. Although the origin of AI viruses affecting poultry is wild aquatic birds, the role of these later birds in further dispersal of poultry-adapted AI viruses is not clear. Previously, we showed that HPAI viruses isolated early from poultry outbreaks could still infect and transmit well in mallards. In this study, we demonstrate that the Mexican H7N3 HPAI virus after four years of circulation in chickens replicates poorly and does not transmit in mallards, but still remains highly pathogenic in chickens. This information on changes in host adaptation is important for understanding the epidemiology of AI viruses and the role that wild waterfowl may play in disseminating viruses adapted to terrestrial poultry.

This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

Keywords: Avian Influenza; H7N3; Poultry; Wild Birds.


Attachment #Patterns of #Human and #Avian #Influenza Viruses to #Trachea and #Colon of 26 #Bird Species – Support for the Community Concept (Front Microbiol., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Front Microbiol. 2019 Apr 18;10:815. doi: 10.3389/fmicb.2019.00815. eCollection 2019.

Attachment Patterns of Human and Avian Influenza Viruses to Trachea and Colon of 26 Bird Species – Support for the Community Concept.

Eriksson P1, Lindskog C2, Lorente-Leal V1, Waldenström J3, González-Acuna D4, Järhult JD5, Lundkvist Å1, Olsen B5, Jourdain E6, Ellström P5.

Author information: 1 Zoonosis Science Center, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden. 2 Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden. 3 Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden. 4 Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán, Chile. 5 Zoonosis Science Center, Department of Medical Sciences, Uppsala University, Uppsala, Sweden. 6 UMR0346 – EPIA, INRA, VetAgro Sup, Saint-Genès-Champanelle, France.



Avian influenza A viruses (AIVs) have a broad host range, but are most intimately associated with waterfowl (Anseriformes) and, in the case of the H13 and H16 subtypes, gulls (Charadriiformes). Host associations are multifactorial, but a key factor is the ability of the virus to bind host cell receptors and thereby initiate infection. The current study aims at investigating the tissue attachment pattern of a panel of AIVs, comprising H3N2, H6N1, H12N5, and H16N3, to avian trachea and colon tissue samples obtained from host species of different orders. Virus attachment was not restricted to the bird species or order from which the virus was isolated. Instead, extensive virus attachment was observed to several distantly related avian species. In general, more virus attachment and receptor expression were observed in trachea than in colon samples. Additionally, a human seasonal H3N2 virus was studied. Unlike the studied AIVs, this virus mainly attached to tracheae from Charadriiformes and a very limited set of avian cola. In conclusion, the reported results highlight the importance of AIV attachment to trachea in many avian species. Finally, the importance of chickens and mallards in AIVs dynamics was illustrated by the abundant AIV attachment observed.

KEYWORDS: avian influenza; birds; lectin staining; pattern of virus attachment; virus histochemistry

PMID: 31057520 PMCID: PMC6482220 DOI: 10.3389/fmicb.2019.00815

Keywords: Avian Influenza; H3N2; H6N1; H12N5; H16N3; Wild Birds; Poultry.


A brief #history of #birdflu (Philos Transact Roy Soc B., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Philos Trans R Soc Lond B Biol Sci. 2019 Jun 24;374(1775):20180257. doi: 10.1098/rstb.2018.0257.

A brief history of bird flu.

Lycett SJ1, Duchatel F1, Digard P1.

Author information: 1 The Roslin Institute, University of Edinburgh , Edinburgh , UK.



In 1918, a strain of influenza A virus caused a human pandemic resulting in the deaths of 50 million people. A century later, with the advent of sequencing technology and corresponding phylogenetic methods, we know much more about the origins, evolution and epidemiology of influenza epidemics. Here we review the history of avian influenza viruses through the lens of their genetic makeup: from their relationship to human pandemic viruses, starting with the 1918 H1N1 strain, through to the highly pathogenic epidemics in birds and zoonoses up to 2018. We describe the genesis of novel influenza A virus strains by reassortment and evolution in wild and domestic bird populations, as well as the role of wild bird migration in their long-range spread. The emergence of highly pathogenic avian influenza viruses, and the zoonotic incursions of avian H5 and H7 viruses into humans over the last couple of decades are also described. The threat of a new avian influenza virus causing a human pandemic is still present today, although control in domestic avian populations can minimize the risk to human health. This article is part of the theme issue ‘Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes’. This issue is linked with the subsequent theme issue ‘Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control’.

KEYWORDS: avian influenza virus; epidemiology; pandemic; phylogenetics; zoonotic

PMID: 31056053 DOI: 10.1098/rstb.2018.0257

Keywords: Pandemic Influenza; Avian Influenza; Spanish Flu; H1N1; Human; Poultry; Wild Birds.


Predicting the initial #spread of novel #Asian origin #influenza A viruses in the continental #USA by wild #waterfowl (Transbound Emerg Dis., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Transbound Emerg Dis. 2019 Mar;66(2):705-714. doi: 10.1111/tbed.13070. Epub 2018 Dec 26.

Predicting the initial spread of novel Asian origin influenza A viruses in the continental USA by wild waterfowl.

Franklin AB1, Bevins SN1, Ellis JW1, Miller RS2, Shriner SA1, Root JJ1, Walsh DP3, Deliberto TJ1.

Author information: 1 U. S. Department of Agriculture, APHIS-WS National Wildlife Research Center, Fort Collins, Colorado. 2 U. S. Department of Agriculture, APHIS-VS Center for Epidemiology and Animal Health, Fort Collins, Colorado. 3 U. S. Geological Survey, National Wildlife Health Center, Madison, Wisconsin.



Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security.

Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

KEYWORDS: Eurasia; influenza A virus; pathogen introduction; surveillance; waterfowl

PMID: 30415502 DOI: 10.1111/tbed.13070 [Indexed for MEDLINE]

Keywords: Avian Influenza; Wild Birds; USA.


Low Pathogenic #Avian #Influenza A (#H5N7) Virus Isolated from a Domestic #Duck in Dongting Lake #Wetland of #China, 2016 (Virol Sin., summary)

[Source: Virologica Sinica, full page: (LINK). Abstract, edited.]

Low Pathogenic Avian Influenza A (H5N7) Virus Isolated from a Domestic Duck in Dongting Lake Wetland of China, 2016

Authors: Liping Ma, Haizhou Liu, Runkun Wang, Tao Jin, Di Liu, George Fu Gao, Quanjiao Chen

Letter / First Online: 04 January 2019


Dear Editor,

The avian influenza virus (AIV) H5N7 was first isolated from wild birds in North America in 2001 (Spackman et al. 2007), and information on only 25 strains of this virus has been deposited in the Global Initiative on Sharing All Influenza Data (GISAID-http://platform.gisaid.org/epi3/frontend#493de3) database until October 30, 2018. Twenty viruses were identified in the United States from 2001 to 2017, three viruses in Denmark in 2003, and two viruses in Mongolia in 2014 (GISAID-http://platform.gisaid.org/epi3/frontend#493de3). All these H5N7 viruses were low pathogenicity and were discovered in wild migratory birds.

Wild migratory birds serve as natural reservoir of AIVs and disseminate the viruses during long-distance migration. Wetlands are important for wild migratory birds as stopover for resting and breeding. In China, millions of domestic ducks are also raised near Dongting Lake Wetland Nature Reverse (Hunan Province Rural Social and Economic Investigation Team 2008)…


Liping Ma and Haizhou Liu contributed equally to this article.


Electronic supplementary material

The online version of this article ( https://doi.org/10.1007/s12250-018-0081-7) contains supplementary material, which is available to authorized users.


This work was funded by the National Science and Technology Major Project (2018ZX10101004), the Open Research Fund Program of Wuhan National Bio-Safety Level 4 Lab of CAS (NBL2017003), China Ministry of Science and Technology (MOST) Key Research and Development Program (2016YFC1200800), and the Shenzhen Science and Technology Research and Development Project (JCYJ20151029151932602). The funding sources had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.


Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflicts of interest.

Animal and Human Rights Statement

This article does not contain any studies with human subjects performed by any of the authors. All studies involving animals were conducted according to the animal welfare guidelines of the World Organisation for Animal Health.

Keywords: Avian Influenza; H5N7; Wild Birds; Poultry; China.


The Critical #Interspecies #Transmission #Barrier at the Animal⁻Human #Interface (Trop Med Infect Dis., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Trop Med Infect Dis. 2019 Apr 25;4(2). pii: E72. doi: 10.3390/tropicalmed4020072.

The Critical Interspecies Transmission Barrier at the Animal⁻Human Interface.

Subbarao K1.

Author information: 1 WHO Collaborating Centre for Reference and Research on Influenza and Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, 792 Elizabeth Street, Melbourne, VIC 3000, Australia. kanta.subbarao@influenzacentre.org.



Influenza A viruses (IAVs) infect humans and a wide range of animal species in nature, and waterfowl and shorebirds are their reservoir hosts. Of the 18 haemagglutinin (HA) and 11 neuraminidase (NA) subtypes of IAV, 16 HA and 9 NA subtypes infect aquatic birds. However, among the diverse pool of IAVs in nature, only a limited number of animal IAVs cross the species barrier to infect humans and a small subset of those have spread efficiently from person to person to cause an influenza pandemic. The ability to infect a different species, replicate in the new host and transmit are three distinct steps in this process. Viral and host factors that are critical determinants of the ability of an avian IAV to infect and spread in humans are discussed.

KEYWORDS: animal–human interface; cross-species infection; influenza; species barrier; zoonoses

PMID: 31027299 DOI: 10.3390/tropicalmed4020072

Keywords: Influenza A; Avian Influenza; Human; Wild Birds; Poultry.