Biological characteristics of influenza virus subtype H6N8 isolated from wild birds in the south of Western Siberia

Aim. The aim is to explore the molecular and biological characteristics of influenza virus subtype H6N8.Material and Methods. Regular collecting of biological samples from wild birds was carried out in 2016 in the south of Western Siberia. Isolation of avian influenza virus strains from birds’ cloacal swabs was performed using three passages in embryonated chicken eggs. Hemagglutination assay was used to detect viruses in the allantoic fluid. Type and subtype of influenza viruses were identified using reverse transcription PCR (RT‐PCR). Results. This is the first time the avian influenza virus H6N8 subtype has been isolated in Russia. Phylogenetic analysis revealed that hemagglutinin (HA) and neuraminidase (NA) segments of A/gadwall/Chany/97/2016(H6N8) strain genome belonged to the Eurasian lineages of avian influenza viruses. Phylogenetic analysis showed that the HA sequence of the strain was closely related to the strain isolated from a duck in Bangladesh in 2015 (A/duck/Bangladesh/25767/2015(H6N1).Conclusion. Avian influenza viruses subtype H6N8 have the ability to circulate among wild waterfowl and poultry, increasing the chance of reassortment and transmission of H6 virus strains among birds. For this reason, it is of crucial importance to strengthen surveillance for avian influenza H6 subtype among wild birds in the south of Western Siberia.

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Molecular and phylogenetic analysis of matrix gene of avian influenza viruses isolated from wild birds and live bird markets in the USA

Influenza and Other Respiratory Viruses ◽

10.1111/irv.12003 ◽

2012 ◽

Vol 7 (4) ◽

pp. 513-520 ◽

Cited By ~ 5

Author(s):

Yogesh Chander ◽

Naresh Jindal ◽

Srinand Sreevatsan ◽

David E. Stallknecht ◽

Sagar M. Goyal

Keyword(s):

Phylogenetic Analysis ◽

Avian Influenza ◽

Wild Birds ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Live Bird Markets ◽

Matrix Gene ◽

The Usa ◽

Live Bird

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Avian influenza viruses in wild birds at the Jeziorsko reservoir in Poland in 2008-2010

Polish Journal of Veterinary Sciences ◽

10.2478/v10181-011-0150-4 ◽

2012 ◽

Vol 15 (2) ◽

pp. 323-328 ◽

Cited By ~ 3

Author(s):

K. Śmietanka ◽

Z. Minta ◽

R. Włodarczyk ◽

K. Wyrostek ◽

M. Jóźwiak ◽

...

Keyword(s):

Influenza Virus ◽

Amino Acid ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Cleavage Site ◽

Wild Birds ◽

Influenza Viruses ◽

Surveillance Study ◽

Avian Influenza Viruses ◽

Amino Acid Motif

Avian influenza viruses in wild birds at the Jeziorsko reservoir in Poland in 2008-2010 During a 3-year surveillance study for avian influenza virus (AIV) infections at the Jeziorsko reservoir in central Poland, 549 oropharyngeal or cloacal swabs from 366 birds of 14 species belonging to 3 orders (Anseriformes, Charadriiformes and Gruiformes) were tested. AIV was detected in 14 birds (3.8%): Common Teals (12x), Mallard (1x) and Garganey (1x). Three potentially dangerous H5 AIV were detected in Common Teals (2x) and Garganey (1x) but all of them revealed a low pathogenic pathotype. A unique cleavage site amino acid motif PQREIR*GLF was found in one H5 isolate from a Garganey.

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Prevalence and diversity of avian influenza viruses in environmental reservoirs

Journal of General Virology ◽

10.1099/vir.0.83369-0 ◽

2008 ◽

Vol 89 (2) ◽

pp. 509-519 ◽

Cited By ~ 62

Author(s):

Andrew S. Lang ◽

Anke Kelly ◽

Jonathan A. Runstadler

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Ha Gene ◽

Culture Independent ◽

Sequencing Part ◽

Valuable Complement ◽

Virus Subtype

Little is known about the ecology and evolution of avian influenza in the natural environment, despite how these affect the potential for transmission. Most work has focused on characterizing viruses isolated from hosts such as waterfowl, and there have also been several instances of isolation and detection from abiotic sources such as water and ice. We used RT-PCR to amplify and characterize the influenza virus sequences present in sediments of ponds that are used heavily by waterfowl. The detection rate of influenza virus was high (>50 %). Characterization of the viruses present by sequencing part of the haemagglutinin (HA) gene showed that there is a diverse collection of viruses in these sediments. We sequenced 117 partial HA gene clones from 11 samples and detected four different HA subtypes (H3, H8, H11 and H12), with approximately 65 % of clone sequences being unique. This culture-independent approach was also able to detect a virus subtype that was not found by sampling of birds in the same geographical region in the same year. Viruses were detected readily in the winter when the ponds were frozen, indicating that these sediments could be a year-to-year reservoir of viruses to infect birds using the ponds, although we have not shown that these viruses are viable. We demonstrate that this approach is a feasible and valuable way to assess the prevalence and diversity of viruses present in the environment, and can be a valuable complement to more difficult viral culturing in attempting to understand the ecology of influenza viruses.

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Protecting Mice from H7 Avian Influenza Virus by Immunisation with a Recombinant Adenovirus Encoding Influenza A Virus Conserved Antigens

BIOpreparations Prevention Diagnosis Treatment ◽

10.30895/2221-996x-2020-20-1-60-67 ◽

2020 ◽

Vol 20 (1) ◽

pp. 60-67

Author(s):

E. S. Sedova ◽

L. V. Verkhovskaya ◽

E. A. Artemova ◽

D. N. Shcherbinin ◽

A. A. Lysenko ◽

...

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Influenza A ◽

Recombinant Adenovirus ◽

Lethal Dose ◽

Influenza Viruses ◽

Avian Influenza Viruses ◽

Protective Properties ◽

Virus Subtype

Influenza is a highly contagious disease that causes annual epidemics and occasional pandemics. Birds are believed to be the source of newly emerging pandemic strains, including highly pathogenic avian influenza viruses of the subtype H7. The aim of the study: to evaluate the ability of the recombinant human adenovirus, serotype 5, which expresses genes of influenza A highly conserved antigens (ion channel M2 and nucleoprotein NP), to provide protection to laboratory mice against infection with a lethal dose of avian influenza virus, subtype H7. To achieve this goal, it was necessary to adapt influenza A virus, subtype H7 for reproduction in the lungs of mice, to characterise it, and to use it for evaluation of the protective properties of the recombinant adenovirus. Materials and methods: avian influenza virus A/Chicken/NJ/294508-12/2004 (H7N2) was adapted for reproduction in the lungs of mice by repeated passages. The adapted strain was sequenced and assessed using hemagglutination test, EID50 and LD50 for laboratory mice. BALB/c mice were immunised once with Ad5-tet-M2NP adenovirus intranasally, and 21 days after the immunisation they were infected with a lethal dose (5 LD50) of influenza virus A/Chicken/NJ/294508-12/2004 (H7N2) in order to assess the protective properties of the recombinant adenovirus. The level of viral shedding from the lungs of the infected mice was evaluated by titration of the lung homogenates in MDCK cell culture on days 3 and 6 after infection. The level of specific antibodies to H7 avian influenza virus was determined by indirect enzyme immunoassay. Results: the use of Ad5-tet-M2NP adenovirus for immunisation of the mice ensured 100% survival of the animals that had disease symptoms (weight loss) after their infection with the lethal dose (5 LD50) of H7 avian influenza virus. The study demonstrated a high post-vaccination level of humoral immune response to H7 avian influenza virus. The virus titer decreased significantly by day 6 in the lungs of mice that had been immunised with Ad5-tet-M2NP compared to the control group. Conclusion: the Ad5-tetM2NP recombinant adenovirus can be used to create a candidate pandemic influenza vaccine that would protect against avian influenza viruses, subtype H7, in particular.

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Antibody responses to avian influenza viruses in wild birds broaden with age

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.2159 ◽

2016 ◽

Vol 283 (1845) ◽

pp. 20162159 ◽

Cited By ~ 11

Author(s):

Sarah C. Hill ◽

Ruth J. Manvell ◽

Bodo Schulenburg ◽

Wendy Shell ◽

Paul S. Wikramaratna ◽

...

Keyword(s):

Avian Influenza ◽

Haemagglutination Inhibition ◽

Wild Birds ◽

Influenza Viruses ◽

Antibody Responses ◽

Immune Recognition ◽

Avian Influenza Viruses ◽

Highly Pathogenic ◽

Age Related ◽

Pathogenic H5n1

For viruses such as avian influenza, immunity within a host population can drive the emergence of new strains by selecting for viruses with novel antigens that avoid immune recognition. The accumulation of acquired immunity with age is hypothesized to affect how influenza viruses emerge and spread in species of different lifespans. Despite its importance for understanding the behaviour of avian influenza viruses, little is known about age-related accumulation of immunity in the virus's primary reservoir, wild birds. To address this, we studied the age structure of immune responses to avian influenza virus in a wild swan population ( Cygnus olor ), before and after the population experienced an outbreak of highly pathogenic H5N1 avian influenza in 2008. We performed haemagglutination inhibition assays on sampled sera for five avian influenza strains and show that breadth of response accumulates with age. The observed age-related distribution of antibody responses to avian influenza strains may explain the age-dependent mortality observed during the highly pathogenic H5N1 outbreak. Age structures and species lifespan are probably important determinants of viral epidemiology and virulence in birds.

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