The Critical Interspecies Transmission Barrier at the Animal–Human Interface

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.

Download Full-text

Influenza A viruses of avian origin circulating in pigs and other mammals.

Acta Biochimica Polonica ◽

10.18388/abp.2014_1861 ◽

2014 ◽

Vol 61 (3) ◽

Cited By ~ 4

Author(s):

Kinga Urbaniak ◽

Andrzej Kowalczyk ◽

Iwona Markowska-Daniel

Keyword(s):

Avian Influenza ◽

Influenza A ◽

Mammalian Species ◽

Swine Influenza ◽

Influenza Viruses ◽

Interspecies Transmission ◽

Influenza A Viruses ◽

Avian Influenza Viruses ◽

Species Barrier ◽

New Host

Influenza A viruses (IAVs) are zoonotic agents, capable of crossing the species barriers. Nowadays, they still constitute a great challenge worldwide. The natural reservoir of all influenza A viruses are wild aquatic birds, despite the fact they have been isolated from a number of avian and mammalian species, including humans. Even when influenza A viruses are able to get into another than waterfowl population, they are often unable to efficiently adapt and transmit between individuals. Only in rare cases, these viruses are capable of establishing a new lineage. To succeed a complete adaptation and further transmission between species, influenza A virus must overcome a species barrier, including adaptation to the receptors of a new host, which would allow the virus-cell binding, virus replication and, then, animal-to-animal transmission. For many years, pigs were thought to be intermediate host for adaptation of avian influenza viruses to humans, because of their susceptibility to infection with both, avian and human influenza viruses, which supported hypothesis of pigs as a 'mixing vessel'. In this review, the molecular factors necessary for interspecies transmission are described, with special emphasis on adaptation of avian influenza viruses to the pig population. In addition, this review gives the information about swine influenza viruses circulating around the world with special emphasis on Polish strains.

Download Full-text

Avian Influenza A Virus Pandemic Preparedness and Vaccine Development

Vaccines ◽

10.3390/vaccines6030046 ◽

2018 ◽

Vol 6 (3) ◽

pp. 46 ◽

Cited By ~ 7

Author(s):

Rory de Vries ◽

Sander Herfst ◽

Mathilde Richard

Keyword(s):

Avian Influenza ◽

Influenza A Virus ◽

Influenza A ◽

Vaccine Development ◽

Influenza Pandemic ◽

Broad Host Range ◽

Influenza A Viruses ◽

Vaccination Strategies ◽

Pandemic Virus ◽

Wide Range

Influenza A viruses can infect a wide range of hosts, creating opportunities for zoonotic transmission, i.e., transmission from animals to humans, and placing the human population at constant risk of potential pandemics. In the last hundred years, four influenza A virus pandemics have had a devastating effect, especially the 1918 influenza pandemic that took the lives of at least 40 million people. There is a constant risk that currently circulating avian influenza A viruses (e.g., H5N1, H7N9) will cause a new pandemic. Vaccines are the cornerstone in preparing for and combating potential pandemics. Despite exceptional advances in the design and development of (pre-)pandemic vaccines, there are still serious challenges to overcome, mainly caused by intrinsic characteristics of influenza A viruses: Rapid evolution and a broad host range combined with maintenance in animal reservoirs, making it near impossible to predict the nature and source of the next pandemic virus. Here, recent advances in the development of vaccination strategies to prepare against a pandemic virus coming from the avian reservoir will be discussed. Furthermore, remaining challenges will be addressed, setting the agenda for future research in the development of new vaccination strategies against potentially pandemic influenza A viruses.

Download Full-text

Revealing interspecies transmission barriers of avian influenza A viruses

10.1101/2020.11.17.386755 ◽

2020 ◽

Author(s):

Mahmoud M. Naguib ◽

Per Eriksson ◽

Elinor Jax ◽

Jonas Nilsson ◽

Carina Sihlbom ◽

...

Keyword(s):

Influenza A ◽

Receptor Expression ◽

Interspecies Transmission ◽

Innate Immune Responses ◽

Influenza A Viruses ◽

Host Interactions ◽

Infection Dynamics ◽

Wide Range ◽

Host Pathogen ◽

New Hosts

AbstractInfluenza A virus (IAV) pandemics result from interspecies transmission events within the avian reservoir and further to mammals including humans. Investigating molecular virus–host interactions dictating this process and the adaptations to the new hosts that follow is vital to understand zoonotic IAV spread. Receptor incompatibility has been suggested to limit zoonotic IAV transmission from the wild bird reservoir. Other barriers to interspecies transmission, particularly within the avian system, largely remain elusive. Through assessment of infection dynamics of mallard origin IAV in two different avian hosts, coupled with studies of receptor expression and host response we aimed to reveal the host-pathogen interactions in a cross-species transmission event. We found that shedding patterns and innate immune responses were highly dependent on viral genotypes, host species and inoculation routes, but less dependent on receptor expression. Further, in contrary to the prevailing dogma we demonstrate that birds can produce a wide range of different sialylated structures also found in mammals, e.g. extended N- and O-linked Neu5Acα2,6 terminated glycans. Overall, receptor incompatibility is not the sole transmission barrier for IAV between birds and to humans, but other host-pathogen factors deserve dedicated studies to achieve proper pandemic preparedness.

Download Full-text

Role of Quail in the Interspecies Transmission of H9 Influenza A Viruses: Molecular Changes on HA That Correspond to Adaptation from Ducks to Chickens

Journal of Virology ◽

10.1128/jvi.77.5.3148-3156.2003 ◽

2003 ◽

Vol 77 (5) ◽

pp. 3148-3156 ◽

Cited By ~ 157

Author(s):

Daniel R. Perez ◽

Wilina Lim ◽

Jon P. Seiler ◽

Guan Yi ◽

Malik Peiris ◽

...

Keyword(s):

Influenza A ◽

Reverse Genetics ◽

Influenza Viruses ◽

Interspecies Transmission ◽

Influenza A Viruses ◽

Species Barrier ◽

Ha Gene ◽

Novel Variants ◽

Efficient Replication

ABSTRACT H9 influenza viruses have become endemic in land-based domestic poultry in Asia and have sporadically crossed to pigs and humans. To understand the molecular determinants of their adaptation to land-based birds, we tested the replication and transmission of several 1970s duck H9 viruses in chickens and quail. Quail were more susceptible than chickens to these viruses, and generation of recombinant H9 viruses by reverse genetics showed that changes in the HA gene are sufficient to initiate efficient replication and transmission in quail. Seven amino acid positions on the HA molecule corresponded to adaptation to land-based birds. In quail H9 viruses, the pattern of amino acids at these seven positions is intermediate between those of duck and chicken viruses; this fact may explain the susceptibility of quail to duck H9 viruses. Our findings suggest that quail provide an environment in which the adaptation of influenza viruses from ducks generates novel variants that can cross the species barrier.

Download Full-text

ViDiT–CACTUS: an inexpensive and versatile library preparation and sequence analysis method for virus discovery and other microbiology applications

Canadian Journal of Microbiology ◽

10.1139/cjm-2018-0097 ◽

2018 ◽

Vol 64 (10) ◽

pp. 761-773 ◽

Cited By ~ 4

Author(s):

Joost T.P. Verhoeven ◽

Marta Canuti ◽

Hannah J. Munro ◽

Suzanne C. Dufour ◽

Andrew S. Lang

Keyword(s):

Influenza A ◽

High Throughput Sequencing ◽

Low Cost ◽

Quality Data ◽

Library Preparation ◽

Virus Discovery ◽

Influenza A Viruses ◽

Wide Range ◽

Functional Profiling ◽

Biology Laboratory

High-throughput sequencing (HTS) technologies are becoming increasingly important within microbiology research, but aspects of library preparation, such as high cost per sample or strict input requirements, make HTS difficult to implement in some niche applications and for research groups on a budget. To answer these necessities, we developed ViDiT, a customizable, PCR-based, extremely low-cost (less than US$5 per sample), and versatile library preparation method, and CACTUS, an analysis pipeline designed to rely on cloud computing power to generate high-quality data from ViDiT-based experiments without the need of expensive servers. We demonstrate here the versatility and utility of these methods within three fields of microbiology: virus discovery, amplicon-based viral genome sequencing, and microbiome profiling. ViDiT–CACTUS allowed the identification of viral fragments from 25 different viral families from 36 oropharyngeal–cloacal swabs collected from wild birds, the sequencing of three almost complete genomes of avian influenza A viruses (>90% coverage), and the characterization and functional profiling of the complete microbial diversity (bacteria, archaea, viruses) within a deep-sea carnivorous sponge. ViDiT–CACTUS demonstrated its validity in a wide range of microbiology applications, and its simplicity and modularity make it easily implementable in any molecular biology laboratory, towards various research goals.

Download Full-text

Avian Influenza Human Infections at the Human-Animal Interface

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa105 ◽

2020 ◽

Vol 222 (4) ◽

pp. 528-537 ◽

Cited By ~ 2

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.

Download Full-text

Eco-Epidemiological Evidence of the Transmission of Avian and Human Influenza A Viruses in Wild Pigs in Campeche, Mexico

Viruses ◽

10.3390/v12050528 ◽

2020 ◽

Vol 12 (5) ◽

pp. 528

Author(s):

Brenda Aline Maya-Badillo ◽

Rafael Ojeda-Flores ◽

Andrea Chaves ◽

Saul Reveles-Félix ◽

Guillermo Orta-Pineda ◽

...

Keyword(s):

Influenza A ◽

Influenza Viruses ◽

Influenza A Viruses ◽

Serum Samples ◽

Fragmented Habitats ◽

Wild Pigs ◽

Wide Range ◽

Influenza Transmission ◽

Human Viruses ◽

Positive Results

Influenza, a zoonosis caused by various influenza A virus subtypes, affects a wide range of species, including humans. Pig cells express both sialyl-α-2,3-Gal and sialyl-α-2,6-Gal receptors, which make them susceptible to infection by avian and human viruses, respectively. To date, it is not known whether wild pigs in Mexico are affected by influenza virus subtypes, nor whether this would make them a potential risk of influenza transmission to humans. In this work, 61 hogs from two municipalities in Campeche, Mexico, were sampled. Hemagglutination inhibition assays were performed in 61 serum samples, and positive results were found for human H1N1 (11.47%), swine H1N1 (8.19%), and avian H5N2 (1.63%) virus variants. qRT-PCR assays were performed on the nasal swab, tracheal, and lung samples, and 19.67% of all hogs were positive to these assays. An avian H5N2 virus, first reported in 1994, was identified by sequencing. Our results demonstrate that wild pigs are participating in the exposure, transmission, maintenance, and possible diversification of influenza viruses in fragmented habitats, highlighting the synanthropic behavior of this species, which has been poorly studied in Mexico.

Download Full-text

Zoonotic Potential of Influenza A Viruses: A Comprehensive Overview

Viruses ◽

10.3390/v10090497 ◽

2018 ◽

Vol 10 (9) ◽

pp. 497 ◽

Cited By ~ 50

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.

Download Full-text