A study of the relationship between #human #infection with #avian #influenza A #H5N6 and environmental avian influenza viruses in #Fujian, #China (BMC Infect Dis., abstract)

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

BMC Infect Dis. 2019 Sep 2;19(1):762. doi: 10.1186/s12879-019-4145-6.

A study of the relationship between human infection with avian influenza a (H5N6) and environmental avian influenza viruses in Fujian, China.

Chen P1, Xie JF1,2, Lin Q2, Zhao L2, Zhang YH2, Chen HB2, Weng YW1,2, Huang Z2, Zheng KC3,4.

Author information: 1 College of Public Health, Fujian Medical University, No. 88, Jiaotong Road, Taijiang District, Fuzhou, 350000, China. 2 Fujian Center for Disease Control and Prevention, Fujian Provincial Key Laboratory of Zoonosis Research, Fuzhou, 350001, China. 3 College of Public Health, Fujian Medical University, No. 88, Jiaotong Road, Taijiang District, Fuzhou, 350000, China. kingdadi9909@126.com. 4 Fujian Center for Disease Control and Prevention, Fujian Provincial Key Laboratory of Zoonosis Research, Fuzhou, 350001, China. kingdadi9909@126.com.




Avian influenza A (H5N6) virus poses a great threat to the human health since it is capable to cross the species barrier and infect humans. Although human infections are believed to largely originate from poultry contaminations, the transmissibility is unclear and only limited information was available on poultry environment contaminations, especially in Fujian Province.


A total of 4901 environmental samples were collected and tested for Avian Influenza Virus (AIV) from six cities in Fujian Province through the Fujian Influenza Surveillance System from 2013 to 2017. Two patient-related samples were taken from Fujian’s first confirmed H5N6 human case and his backyard chicken feces in 2017. Chi-square test or Fisher’s exact probability test was used to compare the AIV and the viral subtype positive rates among samples from different Surveillance cities, surveillance sites, sample types, and seasons. Phylogenetic tree analysis and molecular analysis were conducted to track the viral transmission route of the human infection and to map out the evolutions of H5N6 in Fujian.


The overall positive rate of the H5 subtype AIVs was 4.24% (208/4903). There were distinctive differences (p < 0.05) in the positive rates in samples from different cities, sample sites, sample types and seasons. The viruses from the patient and his backyard chicken feces shared high homologies (99.9-100%) in all the eight gene segments. Phylogenetic trees also showed that these two H5N6 viruses were closely related to each other, and were classified into the same genetic clade with another six H5N6 isolates from the environmental samples. The patient’s H5N6 virus carried genes from H6N6, H5N8 and H5N6 viruses originated from different areas. The R294K or N294S substitution was not detected in the neuraminidase (NA). The S31 N substitution in the matrix2 (M2) gene was detected but only in one strain from the environmental samples.


The H5 subtype of AIVs has started circulating in the poultry environments in Fujian Province. The patient’s viral strain originated from the chicken feces in his backyard. Genetic reassortment in H5N6 viruses in Fujian Province was indicated. The H5N6 viruses currently circulating in Fujian Province were still commonly sensitive to Oseltamivir and Zanamivir, but the resistance against Amantadine has emerged.

KEYWORDS: Avian influenza a (H5N6) virus; Environmental contamination; Phylogenetic analysis

PMID: 31477028 PMCID: PMC6719373 DOI: 10.1186/s12879-019-4145-6 [Indexed for MEDLINE] Free PMC Article

Keywords: Avian Influenza; H5N6; H5N8; H6N6; Reassortant strain; Human; Poultry; Fujian; China.


Comparative Virological and Pathogenic Characteristics of #Avian #Influenza #H5N8 Viruses Detected in #WildBirds and Domestic #Poultry in #Egypt during the Winter of 2016/2017 (Viruses, abstract)

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

Viruses. 2019 Oct 27;11(11). pii: E990. doi: 10.3390/v11110990.

Comparative Virological and Pathogenic Characteristics of Avian Influenza H5N8 Viruses Detected in Wild Birds and Domestic Poultry in Egypt during the Winter of 2016/2017.

Moatasim Y1, Kandeil A1, Aboulhoda BE2, El-Shesheny R1,3, Alkhazindar M4, AbdElSalam ET4, Kutkat O1, Kamel MN1, El Taweel AN1, Mostafa A1, Hicks JT5, Abd Elghaffar SK6, Kayali G7,8, Ali MA1.

Author information: 1 Center of Scientific Excellence for Influenza Virus, Environmental Research Division, National Research Centre, Giza 12622, Egypt. 2 Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Cairo 11562, Egypt. 3 St. Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA. 4 Department of Botany and Microbiology, Faculty of Science, Cairo University, Gamaa Street, Giza 12613, Egypt. 5 Center for Ecology of Infectious Disease, University of Georgia, Athens, GA 30602, USA. 6 Pathology and Clinical Pathology Department, Faculty of Veterinary Medicine, Assuit University, Assuit 71526, Egypt. 7 Human Link, Hazmieh 1109, Lebanon. 8 Department of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas, Houston, TX 77030, USA.



The surveillance and virological characterization of H5N8 avian influenza viruses are important in order to assess their zoonotic potential. The genetic analyses of the Egyptian H5N8 viruses isolated through active surveillance in wild birds and domestic poultry in the winter of 2016/2017 showed multiple introductions of reassortant viruses. In this study, we investigated and compared the growth kinetics, infectivity, and pathogenicity of the three reassortant forms of H5N8 viruses detected in wild birds and domestic poultry in Egypt during the first introduction wave in the winter of 2016/2017. Three representative H5N8 viruses (abbreviated as 813, 871, and 13666) were selected. The 871/H5N8 virus showed enhanced growth properties in vitro in Madin Darby canine kidney (MDCK) and A549 cells. Interestingly, all viruses replicated well in mice without prior adaptation. Infected C57BL/6 mice showed 20% mortality for 813/H5N8 and 60% mortality for 871/H5N8 and 13666/H5N8, which could be attributed to the genetic differences among the viruses. Studies on the pathogenicity in experimentally infected ducks revealed a range of pathogenic effects, with mortality rate ranging from 0% for 813/H5N8 and 13666/H5N8 to 28% for 871/H5N8. No significant differences were observed among the three compared viruses in infected chickens. Overall, different H5N8 viruses had variable biological characteristics, indicating a continuous need for surveillance and virus characterization efforts.

KEYWORDS: Egypt; H5N8; avian influenza virus; pathogenicity

PMID: 31717865 DOI: 10.3390/v11110990

Keywords: Avian Influenza; H5N8; Reassortant strain; Wild Birds; Poultry; Egypt.


Comparative #Pathogenicity and #Transmissibility of the #H7N9 Highly Pathogenic #Avian #Influenza Virus and the H7N9 LPAI Virus in #Chickens (Viruses, abstract)

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

Viruses. 2019 Nov 10;11(11). pii: E1047. doi: 10.3390/v11111047.

Comparative Pathogenicity and Transmissibility of the H7N9 Highly Pathogenic Avian Influenza Virus and the H7N9 Low Pathogenic Avian Influenza Virus in Chickens.

Yu H1, Zhang K1, Ye X1, Wang W1, Wu W1, Wang X1, Guan Y1, He Z1, Wang Y2, Jiao P1.

Author information: 1 College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou 510642, China. 2 Department of Epidemiology, Public Health College, Harbin Medical University, Harbin 150081, China.



There were five outbreaks of H7N9 influenza virus in humans in China since it emerged in 2013, infecting >1000 people. The H7N9 low pathogenic influenza virus was inserted into four amino acids in the HA protein cleavage site to mutate into the H7N9 highly pathogenic virus. This emerging virus caused 15 outbreaks in chickens from the end of 2016 to date. Two H7N9 avian influenza virus (AIV) strains, A/chicken/Guangdong/A46/2013 (LPAIV) and A/chicken/Guangdong/Q29/2017 (HPAIV), were selected to compare the pathogenicity and transmissibility between H7N9 LPAIVs and HPAIVs in chickens. We inoculated 3- to 4-week-old specific-pathogen-free (SPF) chickens with 6 log10EID50/0.1 mL viruses via the ocular-nasal route and co-housed four chickens in each group. The inoculated chicken mortality rate in the A46 and Q29 groups was 1/5 and 5/5, respectively. Q29 virus replication was more efficient compared to the A46 virus in inoculated chickens. Infected chickens initiated viral shedding to naïve contact chickens through respiratory and digestive routes. Both viruses transmitted between chickens by naïve contact, but the Q29 virus had a higher pathogenicity in contact chickens than the A46 virus. Compared with early H7N9 LPAIVs, the pathogenicity and transmissibility of the emerging H7N9 HPAIV was stronger in chickens, indicating that H7N9 influenza virus may continue to threaten human and poultry health.

KEYWORDS: H7N9; avian influenza virus; chickens; pathogenicity; transmissibility

PMID: 31717632 DOI: 10.3390/v11111047

Keywords: Avian Influenza; H7N9; Poultry.


#Genetic, Molecular, and #Pathogenic Characterization of the #H9N2 #Avian #Influenza Viruses Currently Circulating in South #China (Viruses, abstract)

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

Viruses. 2019 Nov 8;11(11). pii: E1040. doi: 10.3390/v11111040.

Genetic, Molecular, and Pathogenic Characterization of the H9N2 Avian Influenza Viruses Currently Circulating in South China.

Sun H1, Lin J1, Liu Z1, Yu Y1, Wu M1, Li S1, Liu Y1, Feng Y1, Wu Y1, Li M1, Jiao P1, Luo K1, Liao M1.

Author information: 1 College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.



The prevalence and variation of the H9N2 avian influenza virus (AIV) pose a threat to public health. A total of eight viruses isolated from farmed poultry in South China during 2017-2018 were selected as representative strains for further systematic study. Phylogenetic analyses indicated that these prevalent viruses belong to the Y280-like lineage and that the internal genes are highly similar to those of recently circulating human H7N9 viruses. The receptor-binding assay showed that most of the H9N2 isolates preferentially bound to the human-like receptor, increasing the risk of them crossing the species barrier and causing human infection. Our in vitro, multi-step growth curve results indicate these viruses can effectively replicate in mammalian cells. Infection in mice showed that three viruses effectively replicated in the lung of mice. Infection in swine revealed that the viruses readily replicated in the upper respiratory tract of pig and effectively induced viral shedding. Our findings suggested that the H9N2 AIVs circulating in poultry recently acquired an enhanced ability to transmit from avian to mammalians, including humans. Based on our findings, we propose that it is essential to strengthen the efforts to surveil and test the pathogenicity of H9N2 AIVs.

KEYWORDS: H9N2; influenza A virus; pathogenicity; pigs; receptor; replication

PMID: 31717393 DOI: 10.3390/v11111040

Keywords: Avian Influenza; H9N2; Poultry.


A novel #reassortant clade highly pathogenic #avian #influenza #H5N6 virus identified in South #Korea in 2018 (Infect Genet Evol., abstract)

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

Infect Genet Evol. 2019 Nov 1:104056. doi: 10.1016/j.meegid.2019.104056. [Epub ahead of print]

A novel reassortant clade highly pathogenic avian influenza H5N6 virus identified in South Korea in 2018.

Baek YG1, Lee YN1, Lee DH2, Cheon SH1, Kye SJ1, Park YR1, Si YJ1, Lee MH1, Lee YJ3.

Author information: 1 Avian Influenza Research & Diagnostic Division, Animal and Plant Quarantine Agency, 177 Hyeoksin 8-ro, Gimcheon-si, Gyeongsangbuk-do 39660, Republic of Korea. 2 Department of Pathobiology and Veterinary Science, The University of Connecticut, 61 North Eagleville Road, Unit-3089, Storrs, CT 06269, United States. 3 Avian Influenza Research & Diagnostic Division, Animal and Plant Quarantine Agency, 177 Hyeoksin 8-ro, Gimcheon-si, Gyeongsangbuk-do 39660, Republic of Korea. Electronic address: leeyj700@korea.kr.



Since 2017, clade H5N6 highly pathogenic avian influenza viruses (HPAIVs) have been detected over a broad geographic region, including Eurasia. These viruses have evolved through reassortment with Eurasian low pathogenic avian influenza viruses (LPAIVs), resulting in multiple genotypes. Here, we sequenced the full-length genome of 15 H5N6 HPAIVs collected from wild birds and poultry farms in South Korea from January to March 2018. A comparative phylogenetic analysis was then conducted. Three distinct genotypes were identified in South Korea during 2017/2018, including a novel reassortant genotype, H214. The novel reassortant H5N6 viruses isolated in this study possessed PB2, PA, and NP gene segments of Eurasian LPAIV on a genetic backbone of the H35-like genotype, which was identified in Korea and the Netherlands during 2017. Bayesian molecular clock analysis suggested that the novel reassortant viruses were generated most likely during the fall migration/wintering season of migratory waterfowl in 2017. Considering the continued emergence and spread of clade HPAIV, enhanced surveillance of wild waterfowl is needed for early detection of HPAIV incursions.

Copyright © 2019. Published by Elsevier B.V.

KEYWORDS: H5N6; HPAIV; Novel genotype; Novel reassortant; Phylogenetic analysis; tMRCA

PMID: 31683010 DOI: 10.1016/j.meegid.2019.104056

Keywords: Avian Influenza; H5N6; Reassortant strain; Poultry; Wild Birds; South Korea.


Opening #Pandora’s Box at the roof of the world: #Landscape, #climate and #avian #influenza (#H5N1) (Acta Trop., abstract)

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

Acta Trop. 2019 Aug;196:93-101. doi: 10.1016/j.actatropica.2019.04.021. Epub 2019 May 4.

Opening Pandora’s Box at the roof of the world: Landscape, climate and avian influenza (H5N1).

Canavan BC1.

Author information: 1 Independent Scholar, Global Health and The Environment, 320 SE 62nd Ave., Portland, Oregon, United States. Electronic address: bcanavan@post.harvard.edu.



The purpose of this case study is to examine how environmental disruption and agricultural practices act synergistically to create a perfect storm for the spread of avian influenza. Actors in this case study include the vast permafrost landscape of the Qinghai-Tibet Plateau; a wild goose that migrates over the Himalayas; the highest altitude railway in the world that traverses the plateau into Tibet; and an avian virus (H5N1). Commencing in 2001, tens of thousands of railway workers travelled to remote regions of the plateau to work on the railway. In order to feed and shelter these workers, the Chinese government established captive-bred goose farms as a source of high protein food. Beginning in 2005 and continuing in subsequent years, Qinghai Lake was the scene for the unprecedented appearance of avian influenza among migratory geese. This was a key moment in the global spread of H5N1 to poultry on three continents. Remote sensing technology suggested an ecological pathway for the transfer of avian viruses among chickens, captive-bred geese, and wild geese. Within a region experiencing rapid climate change, Qinghai Lake is warming even faster than the global average. This may relate to the persistent outbreaks of avian flu strains from Qinghai during the past twelve years. Globally, exponential increases in bird flu outbreaks are not merely a matter of chance mutations in flu viruses but also a result of antecedent social and environmental factors. The Qinghai case study provides real-world examples that bring these factors into sharp focus.

Copyright © 2019 Elsevier B.V. All rights reserved.

KEYWORDS: Agriculture; Avian; Climate; Influenza; Qinghai; Railway

PMID: 31063711 DOI: 10.1016/j.actatropica.2019.04.021 [Indexed for MEDLINE]

Keywords: Avian Influenza; H5N1; Panzootic; Climate change; Global warming; China.


#Pathobiology and innate immune responses of gallinaceous #poultry to clade #H5Nx highly pathogenic #avian #influenza virus #infection (Vet Res., abstract)

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

Vet Res. 2019 Nov 1;50(1):89. doi: 10.1186/s13567-019-0704-5.

Pathobiology and innate immune responses of gallinaceous poultry to clade H5Nx highly pathogenic avian influenza virus infection.

Bertran K1,2, Pantin-Jackwood MJ1, Criado MF1, Lee DH1,3, Balzli CL1,4, Spackman E1, Suarez DL1, Swayne DE5.

Author information: 1 Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA, 30605, USA. 2 IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain. 3 Department of Pathobiology & Veterinary Science, University of Connecticut, Storrs, CT, 06269, USA. 4 Battelle National Biodefense Institute, National Biodefense Analysis and Countermeasures Center, 8300 Research PI, Fort Detrick, MD, 21702, USA. 5 Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, U.S. National Poultry Research Center, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA, 30605, USA. david.swayne@usda.gov.



In the 2014-2015 Eurasian lineage clade H5 highly pathogenic avian influenza (HPAI) outbreak in the U.S., backyard flocks with minor gallinaceous poultry and large commercial poultry (chickens and turkeys) operations were affected. The pathogenesis of the first H5N8 and reassortant H5N2 clade HPAI U.S. isolates was investigated in six gallinaceous species: chickens, Japanese quail, Bobwhite quail, Pearl guinea fowl, Chukar partridges, and Ring-necked pheasants. Both viruses caused 80-100% mortality in all species, except for H5N2 virus that caused 60% mortality in chickens. The surviving challenged birds remained uninfected based on lack of clinical disease and lack of seroconversion. Among the infected birds, chickens and Japanese quail in early clinical stages (asymptomatic and listless) lacked histopathologic findings. In contrast, birds of all species in later clinical stages (moribund and dead) had histopathologic lesions and systemic virus replication consistent with HPAI virus infection in gallinaceous poultry. These birds had widespread multifocal areas of necrosis, sometimes with heterophilic or lymphoplasmacytic inflammatory infiltrate, and viral antigen in parenchymal cells of most tissues. In general, lesions and antigen distribution were similar regardless of virus and species. However, endotheliotropism was the most striking difference among species, with only Pearl guinea fowl showing widespread replication of both viruses in endothelial cells of most tissues. The expression of IFN-γ and IL-10 in Japanese quail, and IL-6 in chickens, were up-regulated in later clinical stages compared to asymptomatic birds.

PMID: 31675983 DOI: 10.1186/s13567-019-0704-5

Keywords: Avian Influenza; H5N1; H5N2; H5N8; Reassortant strain; Poultry; Viral pathogenesis.