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Guo X, Zhou Y, Yan H, An Q, Liang C, Liu L, Qian J. Molecular Markers and Mechanisms of Influenza A Virus Cross-Species Transmission and New Host Adaptation. Viruses 2024; 16:883. [PMID: 38932174 PMCID: PMC11209369 DOI: 10.3390/v16060883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/25/2024] [Accepted: 05/28/2024] [Indexed: 06/28/2024] Open
Abstract
Influenza A viruses continue to be a serious health risk to people and result in a large-scale socio-economic loss. Avian influenza viruses typically do not replicate efficiently in mammals, but through the accumulation of mutations or genetic reassortment, they can overcome interspecies barriers, adapt to new hosts, and spread among them. Zoonotic influenza A viruses sporadically infect humans and exhibit limited human-to-human transmission. However, further adaptation of these viruses to humans may result in airborne transmissible viruses with pandemic potential. Therefore, we are beginning to understand genetic changes and mechanisms that may influence interspecific adaptation, cross-species transmission, and the pandemic potential of influenza A viruses. We also discuss the genetic and phenotypic traits associated with the airborne transmission of influenza A viruses in order to provide theoretical guidance for the surveillance of new strains with pandemic potential and the prevention of pandemics.
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Affiliation(s)
- Xinyi Guo
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China;
| | - Yang Zhou
- Guangzhou Eighth People’s Hospital, Guangzhou Medical University, Guangzhou 510440, China
| | - Huijun Yan
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; (H.Y.); (C.L.)
| | - Qing An
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China;
| | - Chudan Liang
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; (H.Y.); (C.L.)
- Guangdong Provincial Highly Pathogenic Microorganism Science Data Center, Guangzhou 510080, China
| | - Linna Liu
- Guangzhou Eighth People’s Hospital, Guangzhou Medical University, Guangzhou 510440, China
| | - Jun Qian
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China;
- Guangdong Provincial Highly Pathogenic Microorganism Science Data Center, Guangzhou 510080, China
- Shenzhen Key Laboratory of Pathogenic Microbes and Biosafety, Shenzhen 518107, China
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Naiqing X, Tang X, Wang X, Cai M, Liu X, Lu X, Hu S, Gu M, Hu J, Gao R, Liu K, Chen Y, Liu X, Wang X. Hemagglutinin affects replication, stability and airborne transmission of the H9N2 subtype avian influenza virus. Virology 2024; 589:109926. [PMID: 37952465 DOI: 10.1016/j.virol.2023.109926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/19/2023] [Accepted: 10/30/2023] [Indexed: 11/14/2023]
Abstract
H9N2 subtype avian influenza virus (AIV) can transmit by direct as well as airborne contacts. It has been widespread in poultry and continued to contribute to zoonotic spillover events by providing its six internal genes for the reassortment of novel influenza viruses (eg, H7N9) that infect poultry and humans. Compared to H7N9, H9N2 virus displays an efficient airborne transmissibility in poultry, but the mechanisms of transmission difference have been insufficiently studied. The Hemagglutinin (HA) and viral polymerase acidic protein (PA) have been implicated in the airborne transmission of influenza A viruses. Accordingly, we generated the reassortant viruses of circulating airborne transmissible H9N2 and non-airborne transmissible H7N9 viruses carrying HA and/or PA gene. The introduction of the PA gene from H7N9 into the genome of H9N2 virus resulted in a reduction in airborne transmission among chickens, while the isolated introduction of the HA gene segment completely eliminated airborne transmission among chickens. We further showed that introduction of HA gene of non-transmissible H7N9 did not influence the HA/NA balance of H9N2 virus, but increased the threshold for membrane fusion and decreased the acid stability. Thus, our results indicate that HA protein plays a key role in replication, stability, and airborne transmission of the H9N2 subtype AIV.
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Affiliation(s)
- Xu Naiqing
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.
| | - Xinen Tang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.
| | - Xin Wang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.
| | - Miao Cai
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.
| | - Xiaowen Liu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Xiaolong Lu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Shunlin Hu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Min Gu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Jiao Hu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Ruyi Gao
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Kaituo Liu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China.
| | - Yu Chen
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Xiaoquan Wang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
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Xu N, Wang X, Cai M, Tang X, Yang W, Lu X, Liu X, Hu S, Gu M, Hu J, Gao R, Liu K, Chen Y, Liu X, Wang X. Mutations in HA and PA affect the transmissibility of H7N9 avian influenza virus in chickens. Vet Microbiol 2023; 287:109910. [PMID: 38016409 DOI: 10.1016/j.vetmic.2023.109910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/30/2023] [Accepted: 11/04/2023] [Indexed: 11/30/2023]
Abstract
Low pathogenic (LP) H7N9 avian influenza virus (AIV) emerged in 2013 and had spread widely over several months in China, experienced a noteworthy reduction in isolation rate in poultry and human since 2017. Here, we examined the transmission of H7N9 viruses to better understand viral spread and dissemination mechanisms. Three out of four viruses (2013-2016) could transmit in chickens through direct contact, and airborne transmission was confirmed in the JT157 (2016) virus. However, we did not detect the transmission of the two 2017 viruses, WF69 and AH395, through either direct or airborne exposure. Molecular analysis of genome sequence of two viruses identified eleven mutations located in viral proteins (except for matrix protein), such as PA (K362R and S364N) and HA (D167N, H7 numbering), etc. We explored the genetic determinants that contributed to the difference in transmissibility of the viruses in chickens by generating a series of reassortants in the JT157 background. We found that the replacement of HA gene in JT157 by that of WF69 abrogated the airborne transmission in recipient chickens, whereas the combination of HA and PA replacement led to the loss of airborne and direct contact transmission. Failure with contact transmission of the viruses has been associated with the emergence of the mutations D167N in HA and K362R and S364N in PA. Furthermore, the HA D167N mutation significantly reduced viral attachment to chicken lung and trachea tissues, while mutations K362R and S364N in PA reduced the nuclear transport efficiency and the PA protein expression levels in both cytoplasm and nucleus of CEF cells. The D167N substitution in HA reduced the H7N9 viral acid stability and avian-like receptor binding, while enhanced human-like receptor binding. Further analysis revealed these mutants grew poorly in vitro and in vivo. To conclude, H7N9 AIVs that contain mutations in the HA and PA protein reduced the viral transmissibility in chicken, and may pose a reduced threat for poultry but remain a heightened public health risk.
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Affiliation(s)
- Naiqing Xu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xin Wang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Miao Cai
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xinen Tang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Wenhao Yang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xiaolong Lu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China
| | - Xiaowen Liu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Shunlin Hu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Min Gu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Jiao Hu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Ruyi Gao
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Kaituo Liu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Yu Chen
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
| | - Xiaoquan Wang
- Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou University, Yangzhou, Jiangsu, China; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, Yangzhou, China.
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Liao Y, Guo S, Mao N, Li Y, Li J, Long E. Animal experiments on respiratory viruses and analogous studies of infection factors for interpersonal transmission. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:66209-66227. [PMID: 37097557 PMCID: PMC10125856 DOI: 10.1007/s11356-023-26738-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/27/2023] [Indexed: 05/15/2023]
Abstract
Air pollution caused by SARS-CoV-2 and other viruses in human settlements will have a great impact on human health, but also a great risk of transmission. The transmission power of the virus can be represented by quanta number in the Wells-Riley model. In order to solve the problem of different dynamic transmission scenarios, only a single influencing factor is considered when predicting the infection rate, which leads to large differences in quanta calculated in the same space. In this paper, an analog model is established to define the indoor air cleaning index RL and the space ratio parameter. Based on infection data analysis and rule summary in animal experiments, factors affecting quanta in interpersonal communication were explored. Finally, by analogy, the factors affecting person-to-person transmission mainly include viral load of infected person, distance between individuals, etc., the more severe the symptoms, the closer the number of days of illness to the peak, and the closer the distance to the quanta. In summary, there are many factors that affect the infection rate of susceptible people in the human settlement environment. This study provides reference indicators for environmental governance under the COVID-19 epidemic, provides reference opinions for healthy interpersonal communication and human behavior, and provides some reference for accurately judging the trend of epidemic spread and responding to the epidemic.
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Affiliation(s)
- Yuxuan Liao
- MOE Key Laboratory of Deep Earth Science and Engineering, Room 112, College of Architecture and Environment, Administration Building, Sichuan University, No. 24, First Loop South First Section, Chengdu, 610065, China
| | - Shurui Guo
- MOE Key Laboratory of Deep Earth Science and Engineering, Room 112, College of Architecture and Environment, Administration Building, Sichuan University, No. 24, First Loop South First Section, Chengdu, 610065, China
| | - Ning Mao
- Institute for Disaster Management and Reconstruction, Sichuan University, Chengdu, China
| | - Ying Li
- MOE Key Laboratory of Deep Earth Science and Engineering, Room 112, College of Architecture and Environment, Administration Building, Sichuan University, No. 24, First Loop South First Section, Chengdu, 610065, China
| | - Jin Li
- MOE Key Laboratory of Deep Earth Science and Engineering, Room 112, College of Architecture and Environment, Administration Building, Sichuan University, No. 24, First Loop South First Section, Chengdu, 610065, China
| | - Enshen Long
- MOE Key Laboratory of Deep Earth Science and Engineering, Room 112, College of Architecture and Environment, Administration Building, Sichuan University, No. 24, First Loop South First Section, Chengdu, 610065, China.
- Institute for Disaster Management and Reconstruction, Sichuan University, Chengdu, China.
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Adaptation of Two Wild Bird-Origin H3N8 Avian Influenza Viruses to Mammalian Hosts. Viruses 2022; 14:v14051097. [PMID: 35632838 PMCID: PMC9147613 DOI: 10.3390/v14051097] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
Wild birds play an important role in the emergence, evolution, and spread of zoonotic avian influenza viruses (AIVs). However, there are few studies on the cross-species transmission of the H3N8 AIV originating from wild birds. In this study, we investigated the transmissibility and pathogenicity of two H3N8 low pathogenic avian influenza viruses (LPAIVs) isolated from wild birds, GZA1 and XJ47, to mammals. The HA genes of both strains belonged to Eurasian isolates, while the other genes were derived from a variety of other subtypes of AIVs. Both strains can infect specific-pathogen-free (SPF) chickens, BALB/c mice, and guinea pigs. The XJ47 strain spread horizontally in SPF chickens and guinea pigs. The GZA1 strain did not spread horizontally but caused higher weight loss and mild lung inflammation in mice. P12-GZA1- and P12-XJ47-adapted strains obtained after 12 passages in the lung of mice showed enhanced pathogenicity in mice, which led to obvious clinical symptoms, lung inflammation, and 100% death. Both adapted strains have the reported mutation T97I in the PA, and the reported mutation D701N in PB2 has been found in the P12-GZA1-adapted strain. This study provides an important scientific basis for the continuous monitoring of wild AIVs and the mechanism underlying AIV cross-species transmission.
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Cáceres CJ, Rajao DS, Perez DR. Airborne Transmission of Avian Origin H9N2 Influenza A Viruses in Mammals. Viruses 2021; 13:v13101919. [PMID: 34696349 PMCID: PMC8540072 DOI: 10.3390/v13101919] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/16/2021] [Accepted: 09/20/2021] [Indexed: 12/17/2022] Open
Abstract
Influenza A viruses (IAV) are widespread viruses affecting avian and mammalian species worldwide. IAVs from avian species can be transmitted to mammals including humans and, thus, they are of inherent pandemic concern. Most of the efforts to understand the pathogenicity and transmission of avian origin IAVs have been focused on H5 and H7 subtypes due to their highly pathogenic phenotype in poultry. However, IAV of the H9 subtype, which circulate endemically in poultry flocks in some regions of the world, have also been associated with cases of zoonotic infections. In this review, we discuss the mammalian transmission of H9N2 and the molecular factors that are thought relevant for this spillover, focusing on the HA segment. Additionally, we discuss factors that have been associated with the ability of these viruses to transmit through the respiratory route in mammalian species. The summarized information shows that minimal amino acid changes in the HA and/or the combination of H9N2 surface genes with internal genes of human influenza viruses are enough for the generation of H9N2 viruses with the ability to transmit via aerosol.
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Adaptation of H9N2 Influenza Viruses to Mammalian Hosts: A Review of Molecular Markers. Viruses 2020; 12:v12050541. [PMID: 32423002 PMCID: PMC7290818 DOI: 10.3390/v12050541] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/12/2020] [Accepted: 05/12/2020] [Indexed: 11/18/2022] Open
Abstract
As the number of human infections with avian and swine influenza viruses continues to rise, the pandemic risk posed by zoonotic influenza viruses cannot be underestimated. Implementation of global pandemic preparedness efforts has largely focused on H5 and H7 avian influenza viruses; however, the pandemic threat posed by other subtypes of avian influenza viruses, especially the H9 subtype, should not be overlooked. In this review, we summarize the literature pertaining to the emergence, prevalence and risk assessment of H9N2 viruses, and add new molecular analyses of key mammalian adaptation markers in the hemagglutinin and polymerase proteins. Available evidence has demonstrated that H9N2 viruses within the Eurasian lineage continue to evolve, leading to the emergence of viruses with an enhanced receptor binding preference for human-like receptors and heightened polymerase activity in mammalian cells. Furthermore, the increased prevalence of certain mammalian adaptation markers and the enhanced transmissibility of selected viruses in mammalian animal models add to the pandemic risk posed by this virus subtype. Continued surveillance of zoonotic H9N2 influenza viruses, inclusive of close genetic monitoring and phenotypic characterization in animal models, should be included in our pandemic preparedness efforts.
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