scholarly journals Aerosol Transmission of Gull-Origin Iceland Subtype H10N7 Influenza A Virus in Ferrets

2019 ◽  
Vol 93 (13) ◽  
Author(s):  
Minhui Guan ◽  
Jeffrey S. Hall ◽  
Xiaojian Zhang ◽  
Robert J. Dusek ◽  
Alicia K. Olivier ◽  
...  
Keyword(s):  
Binding Affinity ◽  
Direct Contact ◽  
Influenza A ◽  
Sialic Acids ◽  
Influenza A Viruses ◽  
Human Interface ◽  
Genomic Analyses ◽  
Avian Origin ◽  
Glycan Receptors ◽  
Human Infections

ABSTRACTSubtype H10 influenza A viruses (IAVs) have been recovered from domestic poultry and various aquatic bird species, and sporadic transmission of these IAVs from avian species to mammals (i.e., human, seal, and mink) are well documented. In 2015, we isolated four H10N7 viruses from gulls in Iceland. Genomic analyses showed four gene segments in the viruses were genetically associated with H10 IAVs that caused influenza outbreaks and deaths among European seals in 2014. Antigenic characterization suggested minimal antigenic variation among these H10N7 isolates and other archived H10 viruses recovered from human, seal, mink, and various avian species in Asia, Europe, and North America. Glycan binding preference analyses suggested that, similar to other avian-origin H10 IAVs, these gull-origin H10N7 IAVs bound to both avian-like alpha 2,3-linked sialic acids and human-like alpha 2,6-linked sialic acids. However, when the gull-origin viruses were compared with another Eurasian avian-origin H10N8 IAV, which caused human infections, the gull-origin virus showed significantly higher binding affinity to human-like glycan receptors. Results from a ferret experiment demonstrated that a gull-origin H10N7 IAV replicated well in turbinate, trachea, and lung, but replication was most efficient in turbinate and trachea. This gull-origin H10N7 virus can be transmitted between ferrets through the direct contact and aerosol routes, without prior adaptation. Gulls share their habitat with other birds and mammals and have frequent contact with humans; therefore, gull-origin H10N7 IAVs could pose a risk to public health. Surveillance and monitoring of these IAVs at the wild bird-human interface should be continued.IMPORTANCESubtype H10 avian influenza A viruses (IAVs) have caused sporadic human infections and enzootic outbreaks among seals. In the fall of 2015, H10N7 viruses were recovered from gulls in Iceland, and genomic analyses showed that the viruses were genetically related with IAVs that caused outbreaks among seals in Europe a year earlier. These gull-origin viruses showed high binding affinity to human-like glycan receptors. Transmission studies in ferrets demonstrated that the gull-origin IAV could infect ferrets, and that the virus could be transmitted between ferrets through direct contact and aerosol droplets. This study demonstrated that avian H10 IAV can infect mammals and be transmitted among them without adaptation. Thus, avian H10 IAV is a candidate for influenza pandemic preparedness and should be monitored in wildlife and at the animal-human interface.

Avian Influenza Human Infections at the Human-Animal Interface

2020 ◽  
Vol 222 (4) ◽  
pp. 528-537 ◽  
Author(s):  
Damien A M Philippon ◽  
Peng Wu ◽  
Benjamin J Cowling ◽  
Eric H Y Lau
Keyword(s):  
Avian Influenza ◽  
Influenza A ◽  
Control Strategies ◽  
Influenza Pandemic ◽  
World Health ◽  
Emerging Pathogens ◽  
Influenza A Viruses ◽  
Dead Bird ◽  
Risk Of Death ◽  
Human Infections

Abstract Background Avian influenza A viruses (AIVs) are among the most concerning emerging and re-emerging pathogens because of the potential risk for 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. Methods 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. Results We described the characteristics of more than 2500 laboratory-confirmed human infections with AIVs. Human infections with H5N1 and H7N9 were more frequently reported than other subtypes. 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 was mostly reported by H7N9, H5N6, and H10N8 cases, while exposure to sick or dead bird was mostly reported by H5N1, H7N2, H7N3, H7N4, H7N7, and H10N7 cases. Conclusions Understanding the profile of human cases of different AIV subtypes would guide control strategies. Continued monitoring of human infections with AIVs is essential for pandemic preparedness.

scholarly journals Zoonotic Potential of Influenza A Viruses: A Comprehensive Overview

Viruses ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 497 ◽  
Author(s):  
Ahmed Mostafa ◽  
Elsayed Abdelwhab ◽  
Thomas Mettenleiter ◽  
Stephan Pleschka
Keyword(s):  
Genetic Diversity ◽  
Global Health ◽  
Influenza A ◽  
Viral Evolution ◽  
Zoonotic Potential ◽  
Influenza A Viruses ◽  
Comprehensive Overview ◽  
High Genetic Diversity ◽  
Human Interface ◽  
Animal Hosts

Influenza A viruses (IAVs) possess a great zoonotic potential as they are able to infect different avian and mammalian animal hosts, from which they can be transmitted to humans. This is based on the ability of IAV to gradually change their genome by mutation or even reassemble their genome segments during co-infection of the host cell with different IAV strains, resulting in a high genetic diversity. Variants of circulating or newly emerging IAVs continue to trigger global health threats annually for both humans and animals. Here, we provide an introduction on IAVs, highlighting the mechanisms of viral evolution, the host spectrum, and the animal/human interface. Pathogenicity determinants of IAVs in mammals, with special emphasis on newly emerging IAVs with pandemic potential, are discussed. Finally, an overview is provided on various approaches for the prevention of human IAV infections.

scholarly journals H5N1 Influenza A Virus PB1-F2 Relieves HAX-1-Mediated Restriction of Avian Virus Polymerase PA in Human Lung Cells

2018 ◽  
Vol 92 (11) ◽  
pp. e00425-18 ◽  
Author(s):  
B. Mazel-Sanchez ◽  
I. Boal-Carvalho ◽  
F. Silva ◽  
R. Dijkman ◽  
M. Schmolke
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Influenza Viruses ◽  
Zoonotic Transmission ◽  
Restriction Factor ◽  
Influenza A Viruses ◽  
Human Lung Cells ◽  
Enzymatic Function ◽  
H5n1 Influenza ◽  
Avian Origin

ABSTRACTHighly pathogenic influenza A viruses (IAV) from avian hosts were first reported to directly infect humans 20 years ago. However, such infections are rare events, and our understanding of factors promoting or restricting zoonotic transmission is still limited. One accessory protein of IAV, PB1-F2, was associated with pathogenicity of pandemic and zoonotic IAV. This short (90-amino-acid) peptide does not harbor an enzymatic function. We thus identified host factors interacting with H5N1 PB1-F2, which could explain its importance for virulence. PB1-F2 binds to HCLS1-associated protein X1 (HAX-1), a recently identified host restriction factor of the PA subunit of IAV polymerase complexes. We demonstrate that the PA of a mammal-adapted H1N1 IAV is resistant to HAX-1 imposed restriction, while the PA of an avian-origin H5N1 IAV remains sensitive. We also showed HAX-1 sensitivity for PAs of A/Brevig Mission/1/1918 (H1N1) and A/Shanghai/1/2013 (H7N9), two avian-origin zoonotic IAV. Inhibition of H5N1 polymerase by HAX-1 can be alleviated by its PB1-F2 through direct competition. Accordingly, replication of PB1-F2-deficient H5N1 IAV is attenuated in the presence of large amounts of HAX-1. Mammal-adapted H1N1 and H3N2 viruses do not display this dependence on PB1-F2 for efficient replication in the presence of HAX-1. We propose that PB1-F2 plays a key role in zoonotic transmission of avian H5N1 IAV into humans.IMPORTANCEAquatic and shore birds are the natural reservoir of influenza A viruses from which the virus can jump into a variety of bird and mammal host species, including humans. H5N1 influenza viruses are a good model for this process. They pose an ongoing threat to human and animal health due to their high mortality rates. However, it is currently unclear what restricts these interspecies jumps on the host side or what promotes them on the virus side. Here we show that a short viral peptide, PB1-F2, helps H5N1 bird influenza viruses to overcome a human restriction factor of the viral polymerase complex HAX-1. Interestingly, we found that human influenza A virus polymerase complexes are already adapted to HAX-1 and do not require this function of PB1-F2. We thus propose that a functional full-length PB1-F2 supports direct transmission of bird viruses into humans.

scholarly journals Limited Antigenic Diversity in Contemporary H7 Avian-Origin Influenza A Viruses from North America

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Yifei Xu ◽  
Elizabeth Bailey ◽  
Erica Spackman ◽  
Tao Li ◽  
Hui Wang ◽  
...  
Keyword(s):  
North America ◽  
Influenza A ◽  
Influenza A Viruses ◽  
Antigenic Diversity ◽  
Avian Origin

scholarly journals Avian-origin H3N2 canine influenza A viruses in Southern China

2010 ◽  
Vol 10 (8) ◽  
pp. 1286-1288 ◽  
Author(s):  
Shoujun Li ◽  
Zhihai Shi ◽  
Peirong Jiao ◽  
Guihong Zhang ◽  
Zhiwen Zhong ◽  
...  
Keyword(s):  
Influenza A ◽  
Southern China ◽  
Influenza A Viruses ◽  
Avian Origin ◽  
Canine Influenza

scholarly journals Influenza A Virus Strains Differ in Sensitivity to the Antiviral Action of Mx-GTPase

2008 ◽  
Vol 82 (7) ◽  
pp. 3624-3631 ◽  
Author(s):  
Jan Dittmann ◽  
Silke Stertz ◽  
Daniel Grimm ◽  
John Steel ◽  
Adolfo García-Sastre ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Influenza Viruses ◽  
Host Responses ◽  
Influenza A Viruses ◽  
Species Barrier ◽  
Spanish Flu ◽  
Avian Origin ◽  
Flu Virus ◽  
Virus Strains

ABSTRACT Interferon-mediated host responses are of great importance for controlling influenza A virus infections. It is well established that the interferon-induced Mx proteins possess powerful antiviral activities toward most influenza viruses. Here we analyzed a range of influenza A virus strains for their sensitivities to murine Mx1 and human MxA proteins and found remarkable differences. Virus strains of avian origin were highly sensitive to Mx1, whereas strains of human origin showed much weaker responses. Artificial reassortments of the viral components in a minireplicon system identified the viral nucleoprotein as the main target structure of Mx1. Interestingly, the recently reconstructed 1918 H1N1 “Spanish flu” virus was much less sensitive than the highly pathogenic avian H5N1 strain A/Vietnam/1203/04 when tested in a minireplicon system. Importantly, the human 1918 virus-based minireplicon system was almost insensitive to inhibition by human MxA, whereas the avian influenza A virus H5N1-derived system was well controlled by MxA. These findings suggest that Mx proteins provide a formidable hurdle that hinders influenza A viruses of avian origin from crossing the species barrier to humans. They further imply that the observed insensitivity of the 1918 virus-based replicon to the antiviral activity of human MxA is a hitherto unrecognized characteristic of the “Spanish flu” virus that may contribute to the high virulence of this unusual pandemic strain.

scholarly journals Origins and Evolutionary Dynamics of H3N2 Canine Influenza Virus

2015 ◽  
Vol 89 (10) ◽  
pp. 5406-5418 ◽  
Author(s):  
Henan Zhu ◽  
Joseph Hughes ◽  
Pablo R. Murcia
Keyword(s):  
Influenza Virus ◽  
North American ◽  
Influenza A ◽  
Influenza Viruses ◽  
Animal Origin ◽  
Influenza A Viruses ◽  
Canine Influenza Virus ◽  
Zoonotic Infections ◽  
Avian Origin ◽  
Canine Influenza

ABSTRACTInfluenza A viruses (IAVs) are maintained mainly in wild birds, and despite frequent spillover infections of avian IAVs into mammals, only a small number of viruses have become established in mammalian hosts. A new H3N2 canine influenza virus (CIV) of avian origin emerged in Asia in the mid-2000s and is now circulating in dog populations of China and South Korea, and possibly in Thailand. The emergence of CIV provides new opportunities for zoonotic infections and interspecies transmission. We examined 14,764 complete IAV genomes together with all CIV genomes publicly available since its first isolation until 2013. We show that CIV may have originated as early as 1999 as a result of segment reassortment among Eurasian and North American avian IAV lineages. We also identified amino acid changes that might have played a role in CIV emergence, some of which have not been previously identified in other cross-species jumps. CIV evolves at a lower rate than H3N2 human influenza viruses do, and viral phylogenies exhibit geographical structure compatible with high levels of local transmission. We detected multiple intrasubtypic and heterosubtypic reassortment events, including the acquisition of the NS segment of an H5N1 avian influenza virus that had previously been overlooked. In sum, our results provide insight into the adaptive changes required by avian viruses to establish themselves in mammals and also highlight the potential role of dogs to act as intermediate hosts in which viruses with zoonotic and/or pandemic potential could originate, particularly with an estimated dog population of ∼700 million.IMPORTANCEInfluenza A viruses circulate in humans and animals. This multihost ecology has important implications, as past pandemics were caused by IAVs carrying gene segments of both human and animal origin. Adaptive evolution is central to cross-species jumps, and this is why understanding the evolutionary processes that shape influenza A virus genomes is key to elucidating the mechanisms underpinning viral emergence. An avian-origin canine influenza virus (CIV) has recently emerged in dogs and is spreading in Asia. We reconstructed the evolutionary history of CIV and show that it originated from both Eurasian and North American avian lineages. We also identified the mutations that might have been responsible for the cross-species jump. Finally, we provide evidence of multiple reassortment events between CIV and other influenza viruses (including an H5N1 avian virus). This is a cause for concern, as there is a large global dog population to which humans are highly exposed.

scholarly journals Systemic infection with highly pathogenic H5N8 of avian origin produces encephalitis and mortality in wild mammals at a UK rehabilitation centre

2021 ◽  
Author(s):  
Tobias Floyd ◽  
Ashley C Banyard ◽  
Fabian ZX Lean ◽  
Alexander MP Byrne ◽  
Edward Fullick ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Influenza A ◽  
Wild Bird ◽  
Influenza A Viruses ◽  
Rehabilitation Centre ◽  
Highly Pathogenic ◽  
Wild Mammals ◽  
Domestic Poultry ◽  
Avian Origin ◽  
The Impact

Europe has experienced extensive outbreaks of highly pathogenic avian influenza (HPAI) during the autumn/winter 2020/21 season. These avian influenza A viruses are highly transmissible and have infected over 1000 commercial and backyard poultry premises in Europe in this period causing high mortality. The impact on wild bird populations has also been significant, with over 400 detections in at least 47 different species reported across Europe as being positive with the H5N8 virus. Although different H5Nx combinations within the H5 clade 2.3.4.4b have been detected, the H5N8 subtype has predominated both in wild birds and domestic poultry outbreaks. In the UK there have been 22 outbreaks of H5N8 in domestic poultry and captive birds and more than 300 wild bird detections involving H5N8 over the autumn/winter 2020/21 period to April 2021. Here we detail the series of events surrounding the detection of an H5N8 influenza A virus of avian origin in five swans, a fox and three seals in a wildlife rehabilitation centre.

Sign in / Sign up

Export Citation Format

Share Document