#Avian #influenza #human #infections at the human-animal interface (J Infect Dis., abstract)

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

Avian influenza human infections at the human-animal interface

Damien A M Philippon, Peng Wu, Benjamin J Cowling, Eric H Y Lau

The Journal of Infectious Diseases, jiaa105, https://doi.org/10.1093/infdis/jiaa105

Published: 10 March 2020




Avian influenza A viruses (AIVs) are among the most concerning emerging and re-emerging pathogens because of the potential risk in causing an influenza pandemic with catastrophic impact. The recent increase in domestic animals and poultry worldwide was followed by an increase of human AIV outbreaks reported.


We reviewed the epidemiology of human infections with AIV from the literature including reports from the World Health Organization, extracting information on virus subtype, time, location, age, sex, outcome and exposure.


We described the characteristics of more than 2,500 laboratory-confirmed human infections with AIVs. Human infections with H5N1 and H7N9 were more frequently reported than other subtypes. The risk of death was highest among reported cases infected with H5N1, H5N6, H7N9 and H10N8 infections. Older people and males tended to have a lower risk of infection with most AIV subtypes, except for H7N9. Visiting live poultry markets were mostly reported by H7N9, H5N6 and H10N8 cases, while exposure to sick or dead bird mostly reported by H5N1, H7N2, H7N3, H7N4, H7N7 and H10N7 cases.


Understanding the profile of human cases of different AIV subtypes would guide control strategy. Continued monitoring of human infections with AIVs is essential for pandemic preparedness.

avian influenza, human infection, review

Issue Section:  Review

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Keywords: Avian Influenza; Human; H5N1; H5N6; H7N3; H7N7; H7N9; H9N2; H10N8.


Detection of a #Reassortant #H9N2 #Avian #Influenza Virus with #Intercontinental Gene Segments in a Resident #Australian Chestnut #Teal (Viruses, abstract)

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

Viruses. 2020 Jan 13;12(1). pii: E88. doi: 10.3390/v12010088.

Detection of a Reassortant H9N2 Avian Influenza Virus with Intercontinental Gene Segments in a Resident Australian Chestnut Teal.

Bhatta TR1,2, Chamings A1,2, Vibin J1,2, Klaassen M1,3, Alexandersen S1,2,4.

Author information: 1 Geelong Centre for Emerging Infectious Diseases, Geelong, Victoria 3220, Australia. 2 School of Medicine, Deakin University, Geelong, Victoria 3220, Australia. 3 Centre for Integrative Ecology, Deakin University, Victoria 3220, Australia. 4 Barwon Health, University Hospital Geelong, Geelong, Victoria 3220, Australia.



The present study reports the genetic characterization of a low-pathogenicity H9N2 avian influenza virus, initially from a pool and subsequently from individual faecal samples collected from Chestnut teals (Anas castanea) in southeastern Australia. Phylogenetic analyses of six full gene segments and two partial gene segments obtained from next-generation sequencing showed that this avian influenza virus, A/Chestnut teal/Australia/CT08.18/12952/2018 (H9N2), was a typical, low-pathogenicity, Eurasian aquatic bird lineage H9N2 virus, albeit containing the North American lineage nucleoprotein (NP) gene segment detected previously in Australian wild birds. This is the first report of a H9N2 avian influenza virus in resident wild birds in Australia, and although not in itself a cause of concern, is a clear indication of spillover and likely reassortment of influenza viruses between migratory and resident birds, and an indication that any lineage could potentially be introduced in this way.

KEYWORDS: Chestnut teal; Eurasian lineage; H9N2; avian influenza virus; low pathogenicity; phylogenetic analysis; reassortant

PMID: 31940999 DOI: 10.3390/v12010088

Keywords: Avian Influenza; H9N2; Wild Birds; Reassortant strain; Australia.


Detection and #Isolation of #H9N2 Subtype of #Avian #Influenza Virus in House #Sparrows (Passer domesticus) of Ahvaz, #Iran (Arch Razi Inst., abstract)

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

Arch Razi Inst. 2019 Dec;74(4):439-444. doi: 10.22092/ari.2019.122504.1223. Epub 2019 Dec 1.

Detection and Isolation of H9N2 Subtype of Avian Influenza Virus in House Sparrows (Passer domesticus) of Ahvaz, Iran.

Broomand Z1,1, Mayahi M1, Hosseini H2, Valadbeigi S1.

Author information: 1 Department of avian health and diseases, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran. 2 Department of Clinical Sciences, Faculty of Veterinary Medicine, Karaj Branch, Islamic Azad University, Alborz, Iran.



Avian influenza (AI) is an acute infectious disease with worldwide significance causing extensive economic losses in the poultry industry. Avian influenza viruses (AIVs) belong to the family Orthomyxoviridae and categorized in the genus influenza virus A. These viruses have been isolated from more than 100 species of free-living birds. Migratory birds are considered as reservoirs for AIVs and are the major agents responsible for global outbreaks. The Passeriformes are found in most parts of the world and cover a variety of habitats from rural to urban areas. House sparrows are members of the family Passeridae and due to their free flying, are strongly associated with seabirds, indigenous, and industrial poultry. The aim of this study was to determine the role of house sparrows in AIV (H9N2) circulation in the Ahvaz region. The intestinal and tracheal samples were taken from 200 sparrows around Ahvaz during 2017. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed using specific primers in order to detect M and H9 genes of AIVs. The positive specimens in the PCR for the M gene were inoculated into 9-11-day-old embryonated chicken eggs via the allantoic fluid. The results showed that 11 out of 200 samples were positive for the two genes of M and H9. According to the findings of the present study, house sparrows are infected with H9N2 and pose a threat to commercial poultry. These birds may play a significant role in the transmission of AIV between wildlife and domestic animals. Therefore, this issue is important to be considered in preventive measurements.

Copyright © 2019, Archives of Razi Institute. Published by Kowsar.

KEYWORDS: Ahvaz; Avian influenza; House sparrows; Iran; Molecular detection

PMID: 31939262 DOI: 10.22092/ari.2019.122504.1223

Keywords: Avian Influenza; H9N2; Wild Birds; Poultry; Iran.


#Human-infecting #influenza A (#H9N2) virus: A forgotten potential #pandemic strain? (Zoonoses Public Health, abstract)

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

Zoonoses Public Health. 2020 Jan 12. doi: 10.1111/zph.12685. [Epub ahead of print]

Human-infecting influenza A (H9N2) virus: A forgotten potential pandemic strain?

Song W1,2, Qin K3.

Author information: 1 State Key Laboratory of Respiratory Disease, Institute of Integration of Traditional and Western Medicine, Guangzhou Medical University, Guangzhou, China. 2 Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China. 3 National Institute of Viral Disease Control and Prevention, China CDC, Beijing, China.



Continuously emergence of human infection with avian influenza A virus poses persistent threat to human health, as illustrated in H5N1, H7N9 and recent surge of H9N2 infections. Long-term prevalence of H9N2 avian influenza A virus in China and adjacent regions favours the interspecies transmissions from avian to human. Establishment of multiple genotypes of H9N2 variants in this region contributes to the emergence of novel H7N9 and H10N8 viruses which caused human fatalities. Recent increasing human infection with H9N2 virus in China highlights the necessity to closely monitor the interspecies transmission events. Available human H9N2 sequences revealed that Y280/G9 lineage was responsible for the most of human cases. Presence of adaptive mutations beyond the human-like receptor binding was indicative of the capacity of readily infecting new hosts without prior adaptation. Moreover, enlarged host range of H9N2 virus in this region substantially increased the transmission among mammals. Meanwhile, serological surveys implied human was more susceptible to H9N2 infection, compared with panzootic H5 and H7 subtype avian influenza virus. Thus, control at the source will be the ultimate and effective option for H9N2 pandemic preparedness. This review comprehensively summarized recent updates on H9N2 human infections, aiming to shed light on the prevention strategies against this strain with pandemic potential.

© 2020 Blackwell Verlag GmbH.

KEYWORDS: H9N2; influenza; pandemic

PMID: 31930694 DOI: 10.1111/zph.12685

Keywords: Avian Influenza; H9N2; Pandemic Preparedness.


Modification of neutralizing epitopes of #hemagglutinin for the #development of broadly protective #H9N2 #vaccine (Vaccine, abstract)

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

Vaccine. 2020 Jan 7. pii: S0264-410X(19)31634-2. doi: 10.1016/j.vaccine.2019.11.080. [Epub ahead of print]

Modification of neutralizing epitopes of hemagglutinin for the development of broadly protective H9N2 vaccine.

Poh ZW1, Wang Z1, Kumar SR1, Yong HY1, Prabakaran M2.

Author information: 1 Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore. 2 Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore. Electronic address: prabakar@tll.org.sg.



The H9N2 avian influenza viruses cause significant economic losses in poultry worldwide and could potentially cause human pandemic. Currently, the available vaccines have limited efficacy due to antigenic drift of H9N2. To improve vaccine efficacy, we developed monovalent vaccine strain via the modification of neutralizing epitopes on hemagglutinin (HA) to broaden the protection against H9N2 viruses. In this study, single and multiple mutation were introduced to amino acid at position 148, 150 (site I) and 183, 186, 188 (site II) on the full-length HA gene of H9N2 strain (A/Hong Kong/33982/2009). These mutant HA constructs were displayed on the baculovirus surface (BacH9), and evaluated for their cross-protective efficacy against H9N2 viruses in a mouse model. Our findings indicate that mice immunized with multiple BacH9 mutant constructs (148-150 183 and 186) induced cross-protective immunity against circulating H9N2 in the viral challenge study and prove to be a promising vaccine candidate for H9N2.

Copyright © 2019 Elsevier Ltd. All rights reserved.

KEYWORDS: Baculoviral display HA; H9N2; Monovalent vaccine strain; Neutralizing epitope

PMID: 31924429 DOI: 10.1016/j.vaccine.2019.11.080

Keywords: Avian Influenza; H9N2; Vaccines; Animal models.


Distribution of #Avian #Influenza A Viruses in #Poultry-Related #Environment and Its Association with #Human #Infection in #Henan, 2016 to 2017 (Biomed Environ Sci., abstract)

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

Biomed Environ Sci. 2019 Nov;32(11):797-803. doi: 10.3967/bes2019.101.

Distribution of Avian Influenza A Viruses in Poultry-Related Environment and Its Association with Human Infection in Henan, 2016 to 2017.

Ma HX1, Wang RL2, Nie YF2, Su J2, Li DX1, Li Y1, DU YH1, Wei HY1, Li XL1, Wang Z2, Xu BL1, Huang XY1.

Author information: 1 Henan Centers for Disease Control and Prevention, Zhengzhou 450016, Henan, China; Key Laboratory of Pathogenic Microorganisms of Henan Province, Zhengzhou 450016, Henan, China. 2 Henan Centers for Disease Control and Prevention, Zhengzhou 450016, Henan, China.




To survey avian influenza A viruses (AIVs) in the environment and explore the reasons for the surge in human H7N9 cases.


A total of 1,045 samples were collected from routine surveillance on poultry-related environments and 307 samples from human H7N9 cases-exposed environments in Henan from 2016 to 2017. The nucleic acids of influenza A (Flu A), H5, H7, and H9 subtypes were detected by real-time polymerase chain reaction.


A total of 27 H7N9 cases were confirmed in Henan from 2016 to 2017, 24 had a history of live poultry exposure, and 15 had H7N9 virus detected in the related live poultry markets (LPMs). About 96% (264/275) Flu A positive-environmental samples were from LPMs. H9 was the main AIV subtype (10.05%) from routine surveillance sites with only 1 H7-positive sample, whereas 21.17% samples were H7-positive in H7N9 cases-exposed environments. Samples from H7N9 cases-exposed LPMs (47.56%) had much higher AIVs positive rates than those from routine surveillance sites (12.34%). The H7+H9 combination of mixed infection was 78.18% (43/55) of H7-positive samples and 41.34% (43/104) of H9-positive samples.


The contamination status of AIVs in poultry-related environments is closely associated with the incidence of human infection caused by AIVs. Therefore, systematic surveillance of AIVs in LPMs in China is essential for the detection of novel reassortant viruses and their potential for interspecies transmission.

Copyright © 2019 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

KEYWORDS: Avian influenza virus; Exposure environments; Human H7N9 cases; Live poultry market; Routine surveillance

PMID: 31910937 DOI: 10.3967/bes2019.101

Keywords: Avian Influenza; H7N9; H9N2; Poultry; Human; China; Henan.


Adaptive amino acid #substitutions enable #transmission of an #H9N2 #avian #influenza virus in guinea pigs (Sci Rep., abstract)

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

Sci Rep. 2019 Dec 24;9(1):19734. doi: 10.1038/s41598-019-56122-6.

Adaptive amino acid substitutions enable transmission of an H9N2 avian influenza virus in guinea pigs.

Lina L1, Saijuan C2, Chengyu W3, Yuefeng L1, Shishan D2, Ligong C2, Kangkang G2, Zhendong G3, Jiakai L1, Jianhui Z1, Qingping L1, Wenting Z1, Yu S1, Honglin W1, Tengfei Z1, Guoyuan W1, Jiping Z4, Chunmao Z3, Meilin J5, Yuwei G6, Huabin S7, Zongzheng Z8,9.

Author information: 1 Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan, China. 2 Institute of Mountainous Area Research, College of Veterinary Medicine, Hebei Agricultural University, Baoding, 071001, Hebei, China. 3 Institute of Military Veterinary, Academy of Military Medical Sciences, 666 West Liuying Road, Changchun, 130122, Jilin, China. 4 Hubei Engineering Research Center of Viral Vector, Wuhan university of Bioengineering, 430415, Wuhan, China. 5 College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China. 6 Institute of Military Veterinary, Academy of Military Medical Sciences, 666 West Liuying Road, Changchun, 130122, Jilin, China. gaoyuwei@gmail.com. 7 Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan, China. shhb1961@163.com. 8 Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan, China. 329517286@qq.com. 9 Institute of Military Veterinary, Academy of Military Medical Sciences, 666 West Liuying Road, Changchun, 130122, Jilin, China. 329517286@qq.com.



H9N2 is the most prevalent low pathogenic avian influenza virus (LPAIV) in domestic poultry in the world. Two distinct H9N2 poultry lineages, G1-like (A/quail/Hong Kong/G1/97) and Y280-like (A/Duck/Hong Kong/Y280/1997) viruses, are usually associated with binding affinity for both α 2,3 and α 2,6 sialic acid receptors (avian and human receptors), raising concern whether these viruses possess pandemic potential. To explore the impact of mouse adaptation on the transmissibility of a Y280-like virus A/Chicken/Hubei/214/2017(H9N2) (abbreviated as WT), we performed serial lung-to-lung passages of the WT virus in mice. The mouse-adapted variant (MA) exhibited enhanced pathogenicity and advantaged transmissibility after passaging in mice. Sequence analysis of the complete genomes of the MA virus revealed a total of 16 amino acid substitutions. These mutations distributed across 7 segments including PB2, PB1, PA, NP, HA, NA and NS1 genes. Furthermore, we generated a panel of recombinant or mutant H9N2 viruses using reverse genetics technology and confirmed that the PB2 gene governing the increased pathogenicity and transmissibility. The combinations of 340 K and 588 V in PB2 were important in determining the altered features. Our findings elucidate the specific mutations in PB2 contribute to the phenotype differences and emphasize the importance of monitoring the identified amino acid substitutions due to their potential threat to human health.

PMID: 31875046 DOI: 10.1038/s41598-019-56122-6

Keywords: Avian Influenza; H9N2; Animal models.