Submit to Viruses Review for Viruses Propose a Special Issue

Journal Browser

► Journal Browser

Advances in Animal Influenza Virus Research

Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of Viruses (ISSN 1999-4915). This special issue belongs to the section "Animal Viruses".

Deadline for manuscript submissions: closed (30 April 2023) | Viewed by 24116

Share This Special Issue

Special Issue Editors

Dr. Ana Moreno

E-Mail Website
Guest Editor

Virology Department, Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia-Romagna, Via Bianchi 9, 25124 Brescia, Italy
Interests: avian and swine influenza A viruses; influenza D viruses; coronaviruses; suid herpesvirus
Special Issues, Collections and Topics in MDPI journals

Dr. Chiara Chiapponi

E-Mail Website
Guest Editor

WOAH Reference Laboratory for Swine Influenza, Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia-Romagna, 25124 Brescia, Italy
Interests: swine influenza; virus NGS sequencing; influenza D virus; influenza A virus
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In recent years, there has been a significant increase in the number of influenza A virus infections globally in both humans and animals. Of particular concern has recently been the worldwide spread of HPAIV H5, involving a large number of domestic and wild avian species and with recent reports of infections in mammals and wild animals. In 2009, there was a new influenza pandemic from a virus of swine origin, and since 2013, there have been several cases of HP and LPAIV H7N9 virus in poultry with subsequent transmission to humans in China. Swine influenza viruses are also of great concern due to the frequent occurrence of reassortment events and the high antigenic and genetic variability of circulating strains, with negative implications for both the pig industry and public health. The ecology of influenza A viruses is very complex and involves a wide range of avian and mammalian host species. Influenza viruses have high mutation rates and are constantly evolving, allowing the virus to adapt rapidly to changes in the host environment, thus crossing the species barrier and leading to the emergence of new viruses with pandemic potential.

Other influenza B, C and D viruses are also to be considered, and their importance should not be underestimated. Influenza D viruses, discovered only in 2011, were found to be present in cattle, but their ability to infect other species including humans is not yet well understood.

The aim of this Special Issue of Viruses is to provide a complete overview of all aspects relating to animal influenza viruses, such as the ecology of infection, epidemiology and populations at risk, pathogenesis, diagnosis, genetic and antigenic characterization of circulating viruses, phylogenetic analyses, and reassortment and spillover events. Human cases of animal influenza viruses are encouraged. Research papers, review articles and short communications are invited.

Dr. Ana Moreno
Dr. Chiara Chiapponi
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Viruses is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

animal influenza viruses
human infections
animal infections
epidemiology
pathogenesis
genetic characterization
antigenic characterization
reassortment events
spillover

Published Papers (12 papers)

Download All Papers

Research

Jump to: Other

12 pages, 3761 KiB

Open AccessCommunication

Genetic Characterization and Pathogenesis of H5N1 High Pathogenicity Avian Influenza Virus Isolated in South Korea during 2021–2022

by Ra Mi Cha, Yu-Na Lee, Min-Ji Park, Yoon-Gi Baek, Jae-In Shin, Chang Hwa Jung, Mingeun Sagong, Gyeong-Beom Heo, Yong-Myung Kang, Kwang-Nyeong Lee, Youn-Jeong Lee and Eun-Kyoung Lee

Viruses 2023, 15(6), 1403; https://doi.org/10.3390/v15061403 - 20 Jun 2023

Cited by 3 | Viewed by 1980

Abstract

High pathogenicity avian influenza (HPAI) viruses of clade 2.3.4.4 H5Nx have been circulating in poultry and wild birds worldwide since 2014. In South Korea, after the first clade 2.3.4.4b H5N1 HPAI viruses were isolated from wild birds in October 2021, additional HPAIV outbreaks occurred in poultry farms until April 2022. In this study, we genetically characterized clade 2.3.4.4b H5N1 HPAIV isolates in 2021–2022 and examined the pathogenicity and transmissibility of A/mandarin duck/Korea/WA585/2021 (H5N1) (WA585/21) in chickens and ducks. Clade 2.3.4.4b H5N1 HPAI viruses caused 47 outbreaks in poultry farms and were also detected in multiple wild birds. Phylogenetic analysis of HA and NA genes indicated that Korean H5N1 HPAI isolates were closely related to Eurasian viruses isolated in 2021–2022. Four distinct genotypes of H5N1 HPAI viruses were identified in poultry, and the majority were also found in wild birds. WA585/21 inoculated chickens showed virulent pathogenicity with high mortality and transmission. Meanwhile, ducks infected with the virus showed no mortality but exhibited high rates of transmission and longer viral shedding than chickens, suggesting that they may play an important role as silent carriers. In conclusion, consideration of both genetic and pathogenic traits of H5N1 HPAI viruses is required for effective viral control. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

19 pages, 2848 KiB

Open AccessArticle

Efficient and Informative Laboratory Testing for Rapid Confirmation of H5N1 (Clade 2.3.4.4) High-Pathogenicity Avian Influenza Outbreaks in the United Kingdom

by Marek J. Slomka, Scott M. Reid, Alexander M. P. Byrne, Vivien J. Coward, James Seekings, Jayne L. Cooper, Jacob Peers-Dent, Eric Agyeman-Dua, Dilhani de Silva, Rowena D. E. Hansen, Ashley C. Banyard and Ian H. Brown

Viruses 2023, 15(6), 1344; https://doi.org/10.3390/v15061344 - 9 Jun 2023

Cited by 3 | Viewed by 1920

Abstract

During the early stages of the UK 2021-2022 H5N1 high-pathogenicity avian influenza virus (HPAIV) epizootic in commercial poultry, 12 infected premises (IPs) were confirmed by four real-time reverse-transcription–polymerase chain reaction (RRT)-PCRs, which identified the viral subtype and pathotype. An assessment was undertaken to evaluate whether a large sample throughput would challenge laboratory capacity during an exceptionally large epizootic; hence, assay performance across our test portfolio was investigated. Statistical analysis of RRT-PCR swab testing supported it to be focused on a three-test approach, featuring the matrix (M)-gene, H5 HPAIV-specific (H5-HP) and N1 RRT-PCRs, which was successfully assessed at 29 subsequent commercial IPs. The absence of nucleotide mismatches in the primer/probe binding regions for the M-gene and limited mismatches for the H5-HP RRT-PCR underlined their high sensitivity. Although less sensitive, the N1 RRT-PCR remained effective at flock level. The analyses also guided successful surveillance testing of apparently healthy commercial ducks from at-risk premises, with pools of five oropharyngeal swabs tested by the H5-HP RRT-PCR to exclude evidence of infection. Serological testing at anseriform H5N1 HPAIV outbreaks, together with quantitative comparisons of oropharyngeal and cloacal shedding, provided epidemiological information concerning the chronology of initial H5N1 HPAIV incursion and onward spread within an IP. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

7 pages, 237 KiB

Open AccessCommunication

Human Seasonal Influenza Viruses in Swine Workers in Lagos, Nigeria: Consequences for Animal and Public Health

by Abdul-Azeez A. Anjorin, Aurélie Sausy, Claude P. Muller, Judith M. Hübschen, Sunday A. Omilabu and Chantal J. Snoeck

Viruses 2023, 15(6), 1219; https://doi.org/10.3390/v15061219 - 23 May 2023

Cited by 2 | Viewed by 1365

Abstract

The influenza A virus has been scarcely investigated in pigs in Africa, with rare detection prior to 2009. The spread of A(H1N1)pdm09 changed the epidemiology due to frequent human-to-swine transmission and the emergence of various new reassortants. This study therefore aimed at estimating the level of circulation and characterizing influenza A viruses at the interface between swine workers, who are crucial players in the inter-species transmission of influenza A viruses, and their animals in several farms in Nigeria, a hub for pig production in Africa. This cross-sectional study showed that 24.6% (58/236) of the pig serum samples collected in 2013–2014 had anti-influenza A antibodies in the absence of vaccination programs, but none of the pig swabs (n = 1193) were positive according to RT-qPCR. Viral RNA was detected in 0.9% (2/229) of swine workers sampled at their place of work, and the strains were characterized as A(H1N1)pdm09 and seasonal A(H3N2). Our results highlight that more awareness of swine workers regarding the consequences of reverse zoonosis for animal and public health is warranted. Annual vaccination and the wearing of masks when experiencing influenza-like symptoms would help decrease influenza inter-species transmission, while surveillance should be adequately supported for early detection. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

24 pages, 3983 KiB

Open AccessArticle

An Orf-Virus (ORFV)-Based Vector Expressing a Consensus H1 Hemagglutinin Provides Protection against Diverse Swine Influenza Viruses

by Gabriela Mansano do Nascimento, Dina Bugybayeva, Veerupaxagouda Patil, Jennifer Schrock, Ganesh Yadagiri, Gourapura J. Renukaradhya and Diego G. Diel

Viruses 2023, 15(4), 994; https://doi.org/10.3390/v15040994 - 18 Apr 2023

Cited by 5 | Viewed by 1554

Abstract

Influenza A viruses (IAV-S) belonging to the H1 subtype are endemic in swine worldwide. Antigenic drift and antigenic shift lead to a substantial antigenic diversity in circulating IAV-S strains. As a result, the most commonly used vaccines based on whole inactivated viruses (WIVs) provide low protection against divergent H1 strains due to the mismatch between the vaccine virus strain and the circulating one. Here, a consensus coding sequence of the full-length of HA from H1 subtype was generated in silico after alignment of the sequences from IAV-S isolates obtained from public databases and was delivered to pigs using the Orf virus (ORFV) vector platform. The immunogenicity and protective efficacy of the resulting ORFV^Δ121conH1 recombinant virus were evaluated against divergent IAV-S strains in piglets. Virus shedding after intranasal/intratracheal challenge with two IAV-S strains was assessed by real-time RT-PCR and virus titration. Viral genome copies and infectious virus load were reduced in nasal secretions of immunized animals. Flow cytometry analysis showed that the frequency of T helper/memory cells, as well as cytotoxic T lymphocytes (CTLs), were significantly higher in the peripheral blood mononuclear cells (PBMCs) of the vaccinated groups compared to unvaccinated animals when they were challenged with a pandemic strain of IAV H1N1 (CA/09). Interestingly, the percentage of T cells was higher in the bronchoalveolar lavage of vaccinated animals in relation to unvaccinated animals in the groups challenged with a H1N1 from the gamma clade (OH/07). In summary, delivery of the consensus HA from the H1 IAV-S subtype by the parapoxvirus ORFV vector decreased shedding of infectious virus and viral load of IAV-S in nasal secretions and induced cellular protective immunity against divergent influenza viruses in swine. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

11 pages, 1202 KiB

Open AccessArticle

Detecting the Neuraminidase R294K Mutation in Avian Influenza A (H7N9) Virus Using Reverse Transcription Droplet Digital PCR Method

by Xiuyu Lou, Hao Yan, Lingxuan Su, Yi Sun, Xinyin Wang, Liming Gong, Yin Chen, Zhen Li, Zhongbiao Fang, Haiyan Mao, Keda Chen and Yanjun Zhang

Viruses 2023, 15(4), 983; https://doi.org/10.3390/v15040983 - 17 Apr 2023

Viewed by 1119

Abstract

The R294K mutation in neuraminidase (NA) causes resistance to oseltamivir in the avian influenza virus H7N9. Reverse transcription droplet digital polymerase chain reaction (RT-dd PCR) is a novel technique for detecting single-nucleotide polymorphisms. This study aimed to develop an RT-dd PCR method for detecting the R294K mutation in H7N9. Primers and dual probes were designed using the H7N9 NA gene and the annealing temperature was optimized at 58.0 °C. The sensitivity of our RT-dd PCR method was not significantly different from that of RT-qPCR (p = 0.625), but it could specifically detect R294 and 294K in H7N9. Among 89 clinical samples, 2 showed the R294K mutation. These two strains were evaluated using a neuraminidase inhibition test, which revealed that their sensitivity to oseltamivir was greatly reduced. The sensitivity and specificity of RT-dd PCR were similar to those of RT-qPCR and its accuracy was comparable to that of NGS. The RT-dd PCR method had the advantages of absolute quantitation, eliminating the need for a calibration standard curve, and being simpler in both experimental operation and result interpretation than NGS. Therefore, this RT-dd PCR method can be used to quantitatively detect the R294K mutation in H7N9. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

12 pages, 2284 KiB

Open AccessArticle

Statistical Analysis of the Performance of Local Veterinary Laboratories in Molecular Detection (rRT-PCR) of Avian Influenza Virus via National Proficiency Testing Performed during 2020–2022

by Se-Hee An, Gyeong-Beom Heo, Yong-Myung Kang, Mingeun Sagong, Na-Yeong Kim, Youn-Jeong Lee and Kwang-Nyeong Lee

Viruses 2023, 15(4), 823; https://doi.org/10.3390/v15040823 - 24 Mar 2023

Viewed by 1530

Abstract

For the early detection of avian influenza virus (AIV), molecular diagnostic methods such as real-time RT-PCR (rRT-PCR) are the first choice in terms of accuracy and speed in many countries. A laboratory’s capability to perform this diagnostic method needs to be measured through external and independent assessment to ensure that the method is validated within the laboratory and in interlaboratory comparison. The Animal and Plant Quarantine Agency of Korea has implemented five rounds of proficiency testing (PT) for rRT-PCR targeting local veterinary service laboratories involved in the AIV national surveillance program from 2020 to 2022. In each round, a portion composed of six or more samples was selected from the entire PT panel consisting of H5, H7, and H9 viruses isolated in Korea and distributed to each participant, and at least one pair of samples was commonly included in each panel for interlaboratory comparison. During the five rounds of PT, a few incorrect and outlying results were detected that required immediate inspection or corrective actions. However, in the quantitative measurement of Ct values, the average standard deviation or coefficient of variation decreased as multiple PT rounds progressed, and a positive correlation between consecutive rounds of PT was observed since 2021. The better consistency or stability in the experimental performance appeared to contribute to the more harmonized results in the latest PTs, and it is assumed that the positive reaction of participants to the challenges of quantitative assessment reports showing their status intuitively might work. We need to continue operating the PT program for local laboratories because they play crucial roles at the front line of the national avian influenza surveillance program, and frequent changes in the human resources or environment for diagnosis in those laboratories are inevitable. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

15 pages, 2312 KiB

Open AccessArticle

Introductions of Human-Origin Seasonal H3N2, H1N2 and Pre-2009 H1N1 Influenza Viruses to Swine in Brazil

by Caroline Tochetto, Dennis M. Junqueira, Tavis K. Anderson, Danielle Gava, Vanessa Haach, Mauricio E. Cantão, Amy L. Vincent Baker and Rejane Schaefer

Viruses 2023, 15(2), 576; https://doi.org/10.3390/v15020576 - 19 Feb 2023

Cited by 4 | Viewed by 2246

Abstract

In South America, the evolutionary history of influenza A virus (IAV) in swine has been obscured by historically low levels of surveillance, and this has hampered the assessment of the zoonotic risk of emerging viruses. The extensive genetic diversity of IAV in swine observed globally has been attributed mainly to bidirectional transmission between humans and pigs. We conducted surveillance in swine in Brazil during 2011–2020 and characterized 107 H1N1, H1N2, and H3N2 IAVs. Phylogenetic analysis based on HA and NA segments revealed that human seasonal IAVs were introduced at least eight times into swine in Brazil since the mid-late 1980s. Our analyses revealed three genetic clades of H1 within the 1B lineage originated from three distinct spillover events, and an H3 lineage that has diversified into three genetic clades. The N2 segment from human seasonal H1N2 and H3N2 viruses was introduced into swine six times and a single introduction of an N1 segment from the human H1N1 virus was identified. Additional analysis revealed further reassortment with H1N1pdm09 viruses. All these introductions resulted in IAVs that apparently circulate only in Brazilian herds. These results reinforce the significant contributions of human IAVs to the genetic diversity of IAV in swine and reiterate the importance of surveillance of IAV in pigs. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

15 pages, 6207 KiB

Open AccessArticle

Experimental Pathogenicity of H9N2 Avian Influenza Viruses Harboring a Tri-Basic Hemagglutinin Cleavage Site in Sonali and Broiler Chickens

by Jahan Ara Begum, Ismail Hossain, Mohammed Nooruzzaman, Jacqueline King, Emdadul Haque Chowdhury, Timm C. Harder and Rokshana Parvin

Viruses 2023, 15(2), 461; https://doi.org/10.3390/v15020461 - 7 Feb 2023

Cited by 3 | Viewed by 3923

Abstract

Low-pathogenic avian influenza (LPAI) H9N2 virus is endemic in Bangladesh, causing huge economic losses in the poultry industry. Although a considerable number of Bangladeshi LPAI H9N2 viruses have been molecularly characterized, there is inadequate information on the pathogenicity of H9N2 viruses in commercial poultry. In this study, circulating LPAI H9N2 viruses from recent field outbreaks were characterized, and their pathogenicity in commercial Sonali (crossbred) and broiler chickens was assessed. Phylogenetic analysis of currently circulating field viruses based on the hemagglutinin (HA) and neuraminidase (NA) gene sequences revealed continuous circulation of G1 lineages containing the tri-basic hemagglutinin cleavage site (HACS) motif (PAKSKR*GLF) at the HA protein. Both the LPAI susceptible Sonali and broiler chickens were infected with selected H9N2 isolates A/chicken/Bangladesh/2458-LT2/2020 or A/chicken/Bangladesh/2465-LT56/2021 using intranasal (100 µL) and intraocular (100 µL) routes with a dose of 10⁶ EID₅₀/_mL. Infected groups (LT_2-So1 and LT_56-So2; LT_2-Br1 and LT_56-Br2) revealed no mortality or clinical signs. However, at gross and histopathological investigation, the trachea, lungs, and intestine of the LT_2-So1 and LT_56-So2 groups displayed mild to moderate hemorrhages, congestion, and inflammation at different dpi. The LT 2-Br1 and LT 56-Br2 broiler groups showed nearly identical changes in the trachea, lungs, and intestine at various dpi, indicating no influence on pathogenicity in the two commercial bird species under study. Overall, the prominent lesions were observed up to 7 dpi and started to disappear at 10 dpi. The H9N2 viruses predominantly replicated in the respiratory tract, and higher titers of virus were shed through the oropharyngeal route than the cloacal route. Finally, this study demonstrated the continuous evolution of tri-basic HACS containing H9N2 viruses in Bangladesh with a low-pathogenic phenotype causing mild to moderate tracheitis, pneumonia, and enteritis in Sonali and commercial broiler chickens. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

13 pages, 4551 KiB

Open AccessArticle

Identification of Two Isoforms of Canine Tetherin in Domestic Dogs and Characterization of Their Antiviral Activity against Canine Influenza Virus

by Liang Xu, Jiajun Ou, Xuerui Hu, Yanhong Zheng, Shaotang Ye, Lintao Zhong, Zhiying Lai, Siqi Cai, Gang Lu and Shoujun Li

Viruses 2023, 15(2), 393; https://doi.org/10.3390/v15020393 - 30 Jan 2023

Viewed by 1560

Abstract

Canine influenza virus (CIV) significantly threatens the canine population and public health. Tetherin, an innate immune factor, plays an important role in the defense against pathogen invasion and has been discovered to restrict the release of various enveloped viruses. Two isoforms of canine tetherin (tetherin-X1 and tetherin-X2) were identified in peripheral blood leukocytes of mixed-breed dogs using reverse transcription polymerase chain reaction (RT–PCR). Amino acid alignment revealed that relative to full-length tetherin (tetherin-X1) and truncated canine tetherin (tetherin-X2) exhibited deletion of 34 amino acids. The deletion occurred at the C-terminus of the coiled-coiled ectodomain and the N-terminus of the glycosylphosphatidylinositol (GPI)-anchor domain. Tetherin-X2 was localized subcellularly at the cell membrane, which was consistent with the localization of tetherin-X1. In addition, canine tetherin-X1 and tetherin-X2 restricted the release of H3N2 CIV. However, canine tetherin-X1 had higher antiviral activity than canine tetherin-X2, indicating that the C-terminus of the coiled-coiled ectodomain and the N-terminus of the GPI-anchor domain of canine tetherin (containing the amino acids deleted in tetherin-X2) are critical for its ability to restrict H3N2 CIV release. This study provides insights for understanding the key functional domains of tetherin that restrict CIV release. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

12 pages, 1095 KiB

Open AccessArticle

Different Infectivity and Transmissibility of H5N8 and H5N1 High Pathogenicity Avian Influenza Viruses Isolated from Chickens in Japan in the 2021/2022 Season

by Yoshihiro Takadate, Ryota Tsunekuni, Asuka Kumagai, Junki Mine, Yuto Kikutani, Saki Sakuma, Kohtaro Miyazawa and Yuko Uchida

Viruses 2023, 15(2), 265; https://doi.org/10.3390/v15020265 - 17 Jan 2023

Cited by 10 | Viewed by 2917

Abstract

H5N8 and H5N1 high pathogenicity avian influenza viruses (HPAIVs) caused outbreaks in poultry farms in Japan from November 2021 to May 2022. Hemagglutinin genes of these viruses belong to clade 2.3.4.4B and can be divided phylogenetically into the following groups: 20A, 20E, and 21E. In this study, we compared the infectivity and transmissibility of HPAIVs from three groups of chickens. Representative strains from 20A, 20E, and 21E groups are A/chicken/Akita/7C/2021(H5N8)(Akita7C), A/chicken/Kagoshima/21A6T/2021(H5N1)(Kagoshima6T), and A/chicken/Iwate/21A7T/2022(H5N1)(Iwate7T), respectively. Fifty percent lethal dose of Akita7C in chickens (10^3.83 fifty percent egg infectious dose (EID50)) was up to seven times lower than those of Kagoshima6T and Iwate7T (10^4.50 and 10^4.68 EID_50, respectively). Mean death times for Akita7C- and Kagoshima6T-infected chickens (3.45 and 3.30 days, respectively) were at least a day longer than that of Iwate7T (2.20 days). Viral titers of the trachea and cloaca of Iwate7T-infected chicken were the highest detected. The transmission rate of the Akita7C strain (100%) was markedly higher than those of the two strains (<50%). These data suggest that the infectivity and transmissibility of the Akita7C strain (H5N8) in chickens are higher than those of H5N1 viruses, providing fundamental information needed for formulating effective prevention and control strategies for HPAI outbreaks. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

14 pages, 2882 KiB

Open AccessArticle

Characterization of Neutralizing Monoclonal Antibodies and Identification of a Novel Conserved C-Terminal Linear Epitope on the Hemagglutinin Protein of the H9N2 Avian Influenza Virus

by Yanan Wang, Xueyang Li, Qianru Xu, Xiangxiang Niu, Shenli Zhang, Xiaotian Qu, Hongyan Chu, Jinxuan Chen, Qianqian Shi, Erqin Zhang and Gaiping Zhang

Viruses 2022, 14(11), 2530; https://doi.org/10.3390/v14112530 - 15 Nov 2022

Cited by 2 | Viewed by 1830

Abstract

The H9N2 avian influenza virus (AIV) remains a serious threat to the global poultry industry and public health. The hemagglutinin (HA) protein is an essential protective antigen of AIVs and a major target of neutralizing antibodies and vaccines. Therefore, in this study, we used rice-derived HA protein as an immunogen to generate monoclonal antibodies (mAbs) and screened them using an immunoperoxidase monolayer assay and indirect enzyme-linked immunosorbent assay. Eight mAbs reacted well with the recombinant H9N2 AIV and HA protein, four of which exhibited potent inhibitory activity against hemagglutination, while three showed remarkable neutralization capacities. Western blotting confirmed that two mAbs bound to the HA protein. Linear epitopes were identified using the mAbs; a novel linear epitope, ⁴⁸⁰HKCDDQCM⁴⁸⁷, was identified. Structural analysis revealed that the novel linear epitope is located at the C-terminus of HA2 near the disulfide bond-linked HA1 and HA2. Alignment of the amino acid sequences showed that the epitope was highly conserved among multiple H9N2 AIV strains. The results of this study provide novel insights for refining vaccine and diagnostic strategies and expand our understanding of the immune response against AIV. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

Other

Jump to: Research

6 pages, 2697 KiB

Open AccessBrief Report

Detection of Influenza D-Specific Antibodies in Bulk Tank Milk from Swedish Dairy Farms

by Ignacio Alvarez, Sara Hägglund, Katarina Näslund, Axel Eriksson, Evelina Ahlgren, Anna Ohlson, Mariette F. Ducatez, Gilles Meyer, Jean-Francois Valarcher and Siamak Zohari

Viruses 2023, 15(4), 829; https://doi.org/10.3390/v15040829 - 24 Mar 2023

Cited by 1 | Viewed by 1202

Abstract

Influenza D virus (IDV) has been detected in bovine respiratory disease (BRD) outbreaks, and experimental studies demonstrated this virus’s capacity to cause lesions in the respiratory tract. In addition, IDV-specific antibodies were detected in human sera, which indicated that this virus plays a potential zoonotic role. The present study aimed to extend our knowledge about the epidemiologic situation of IDV in Swedish dairy farms, using bulk tank milk (BTM) samples for the detection of IDV antibodies. A total of 461 and 338 BTM samples collected during 2019 and 2020, respectively, were analyzed with an in-house indirect ELISA. In total, 147 (32%) and 135 (40%) samples were IDV-antibody-positive in 2019 and 2020, respectively. Overall, 2/125 (2%), 11/157 (7%) and 269/517 (52%) of the samples were IDV-antibody-positive in the northern, middle and southern regions of Sweden. The highest proportion of positive samples was repeatedly detected in the south, in the county of Halland, which is one of the counties with the highest cattle density in the country. In order to understand the epidemiology of IDV, further research in different cattle populations and in humans is required. Full article

(This article belongs to the Special Issue Advances in Animal Influenza Virus Research)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Advances in Animal Influenza Virus Research

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (12 papers)

Research

Other

Further Information

Guidelines

MDPI Initiatives

Follow MDPI