RESUMO
High pathogenicity avian influenza viruses (HPAIVs) have caused major epizootics in recent years, with devastating consequences for poultry and wildlife worldwide. Domestic and wild ducks can be highly susceptible to HPAIVs, and infection leads to efficient viral replication and massive shedding (i.e., high titres for an extended time), contributing to widespread viral dissemination. Importantly, ducks are known to shed high amounts of virus in the earliest phase of infection, but the dynamics and impact of environmental contamination on the epidemiology of HPAIV outbreaks are poorly understood. In this study, we monitored mule ducks experimentally infected with two H5N8 clade 2.3.4.4b goose/Guangdong HPAIVs sampled in France in 2016-2017 and 2020-2021 epizootics. We investigated viral shedding dynamics in the oropharynx, cloaca, conjunctiva, and feathers; bird-to-bird viral transmission; and the role of the environment in viral spread and as a source of samples for early detection and surveillance. Our findings showed that viral shedding started before the onset of clinical signs, i.e., as early as 1 day post-inoculation (dpi) or post-contact exposure, peaked at 4 dpi, and lasted for up to 14 dpi. The detection of viral RNA in aerosols, dust, and water samples mirrored viral shedding dynamics, and viral isolation from these environmental samples was successful throughout the experiment. Our results confirm that mule ducks can shed high HPAIV titres through the four excretion routes tested (oropharyngeal, cloacal, conjunctival, and feather) while being asymptomatic and that environmental sampling could be a non-invasive tool for early viral RNA detection in HPAIV-infected farms.
Assuntos
Patos , Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Doenças das Aves Domésticas , Eliminação de Partículas Virais , Animais , Patos/virologia , Influenza Aviária/virologia , Vírus da Influenza A Subtipo H5N8/fisiologia , Vírus da Influenza A Subtipo H5N8/patogenicidade , Doenças das Aves Domésticas/virologia , França/epidemiologiaRESUMO
While mammals can be infected by influenza A virus either sporadically or with well adapted lineages, aquatic birds are the natural reservoir of the pathogen. So far most of the knowledge on influenza virus dynamics was however gained on mammalian models. In this study, we infected turkeys using a low pathogenic avian influenza virus and determined the infection dynamics with a target-cell limited model. Results showed that turkeys had a different set of infection characteristics, compared with humans and ponies. The viral clearance rates were similar between turkeys and ponies but higher than that in humans. The cell death rates and cell to cell transmission rates were similar between turkeys and humans but higher than those in ponies. Overall, this study indicated the variations of within-host dynamics of influenza infection in avian, humans, and other mammalian systems.
Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Perus , Animais , Perus/virologia , Influenza Aviária/virologia , Influenza Aviária/transmissão , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vírus da Influenza A Subtipo H9N2/fisiologia , Humanos , Cavalos , Infecções por Orthomyxoviridae/virologia , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/transmissão , Influenza Humana/virologiaRESUMO
At the end of 2020, an outbreak of HPAI H5N8 was registered in captive African houbara bustards (Chlamydotis undulata) in the United Arab Emirates. In order to better understand the pathobiology of this viral infection in bustards, a comprehensive pathological characterization was performed. A total of six birds were selected for necropsy, histopathology, immunohistochemistry, RNAscope in situ hybridization and RT-qPCR and nanopore sequencing on formalin-fixed and paraffin-embedded (FFPE) tissue blocks. Gross lesions included mottled and/or hemorrhagic pancreas, spleen and liver and fibrinous deposits on air sacs and intestine. Necrotizing pancreatitis, splenitis and concurrent vasculitis, hepatitis and fibrino-heterophilic peritonitis were identified, microscopically. Viral antigens (nucleoprotein) and RNAs (matrix gene) were both detected within necro-inflammatory foci, parenchymal cells, stromal cells and endothelial cells of affected organs, including the myenteric plexus. Molecular analysis of FFPE blocks successfully detected HPAI H5N8, further confirming its involvement in the lesions observed. In conclusion, HPAI H5N8 in African houbara bustards results in hyperacute/acute forms exhibiting marked pantropism, endotheliotropism and neurotropism. In addition, our findings support the use of FFPE tissues for molecular studies of poorly characterized pathogens in exotic and endangered species, when availability of samples is limited.
Assuntos
Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Animais , Emirados Árabes Unidos/epidemiologia , Células Endoteliais , Virulência , AvesRESUMO
High pathogenicity avian influenza viruses (HPAIVs) H5Nx of clade 2.3.4.4b have been circulating increasingly in both wild and domestic birds in recent years. In turn, this has led to an increase in the number of spillover events affecting mammals. In November 2022, an HPAIV H5N1 caused an outbreak in a zoological park in the south of France, resulting in the death of a Tibetan black bear (Ursus thibetanus) and several captive and wild bird species. We detected the virus in various tissues of the bear and a wild black-headed gull (Chroicocephalus ridibundus) found dead in its enclosure using histopathology, two different in situ detection techniques, and next-generation sequencing, all performed on formalin-fixed paraffin-embedded tissues. Phylogenetic analysis performed on the hemagglutinin gene segment showed that bear and gull strains shared 99.998% genetic identity, making the bird strain the closest related strain. We detected the PB2 E627K mutation in minute quantities in the gull, whereas it predominated in the bear, which suggests that this mammalian adaptation marker was selected during the bear infection. Our results provide the first molecular and histopathological characterization of an H5N1 virus infection in this bear species. IMPORTANCE: Avian influenza viruses are able to cross the species barrier between birds and mammals because of their high genetic diversity and mutation rate. Using formalin-fixed paraffin-embedded tissues, we were able to investigate a Tibetan black bear's infection by a high pathogenicity H5N1 avian influenza virus at the molecular, phylogenetic, and histological levels. Our results highlight the importance of virological surveillance programs in mammals and the importance of raising awareness among veterinarians and zookeepers of the clinical presentations associated with H5Nx virus infection in mammals.
Assuntos
Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Ursidae , Animais , Humanos , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/epidemiologia , Virulência , Filogenia , Inclusão em Parafina , Tibet , Aves , Vírus da Influenza A/genética , FormaldeídoRESUMO
During the recent avian influenza epizootics that occurred in France in 2020/21 and 2021/22, the virus was so contagiousness that it was impossible to control its spread between farms. The preventive slaughter of millions of birds consequently was the only solution available. In an effort to better understand the spread of avian influenza viruses (AIVs) in a rapid and innovative manner, we established an amplicon-based MinION sequencing workflow for the rapid genetic typing of circulating AIV strains. An amplicon-based MinION sequencing workflow based on a set of PCR primers targeting primarily the hemagglutinin gene but also the entire influenza virus genome was developed. Thirty field samples from H5 HPAIV outbreaks in France, including environmental samples, were sequenced using the MinION MK1C. A real-time alignment of the sequences with MinKNOW software allowed the sequencing run to be stopped as soon as enough data were generated. The consensus sequences were then generated and a phylogenetic analysis was conducted to establish links between the outbreaks. The whole sequence of the hemagglutinin gene was obtained for the 30 clinical samples of H5Nx HPAIV belonging to clade 2.3.4.4b. The consensus sequences comparison and the phylogenetic analysis demonstrated links between some outbreaks. While several studies have shown the advantages of MinION for avian influenza virus sequencing, this workflow has been applied exclusively to clinical field samples, without any amplification step on cell cultures or embryonated eggs. As this type of testing pipeline requires only a short amount of time to link outbreaks or demonstrate a new introduction, it could be applied to the real-time management of viral epizootics.
Assuntos
Vírus da Influenza A , Influenza Aviária , Sequenciamento por Nanoporos , Animais , Influenza Aviária/epidemiologia , Filogenia , Hemaglutininas , Fluxo de Trabalho , Surtos de Doenças , Vírus da Influenza A/genéticaRESUMO
Highly pathogenic avian influenza viruses (HPAIV) are a major threat to the global poultry industry and public health due to their zoonotic potential. Since 2016, Europe and France have faced major epizootics caused by clade 2.3.4.4b H5 HPAIV. To reduce sample-to-result times, point-of-care testing is urgently needed to help prevent further outbreaks and the propagation of the virus. This study presents the design of a novel real-time colourimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for the detection of clade 2.3.4.4b H5 HPAIV. A clinical validation of this RT-LAMP assay was performed on 198 pools of clinical swabs sampled in 52 poultry flocks during the H5 HPAI 2020-2022 epizootics in France. This RT-LAMP assay allowed the specific detection of HPAIV H5Nx clade 2.3.4.4b within 30â min with a sensitivity of 86.11%. This rapid, easy-to-perform, inexpensive, molecular detection assay could be included in the HPAIV surveillance toolbox.
Assuntos
Vírus da Influenza A , Influenza Aviária , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Animais , Transcrição Reversa , Influenza Aviária/diagnóstico , Colorimetria/veterinária , Sensibilidade e Especificidade , Vírus da Influenza A/genética , Aves DomésticasRESUMO
IMPORTANCE: With the circulation of high pathogenicity avian influenza viruses having intensified considerably in recent years, the European Union is considering the vaccination of farmed birds. A prerequisite for this vaccination is the implementation of drastic surveillance protocols. Environmental sampling is a relevant alternative to animal sampling. However, environmental samples often contain inhibitory compounds in large enough quantities to inhibit RT-qPCR reactions. As bovine serum albumin is a molecule used in many fields to overcome this inhibitory effect, we tested its use on dust samples from poultry farms in areas heavily affected by HPAIV epizootics. Our results show that its use significantly increases the sensitivity of the method.
Assuntos
Vírus da Influenza A , Influenza Aviária , Doenças das Aves Domésticas , Animais , Soroalbumina Bovina , Poeira , Virulência , Vírus da Influenza A/genética , Aves Domésticas , FilogeniaRESUMO
Respiratory diseases are a health and economic concern for poultry production worldwide. Given global economic exchanges and migratory bird flyways, respiratory viruses are likely to emerge continuously in new territories. The primary aim of this study was to investigate the major pathogens involved in respiratory disease in Tunisian broiler poultry and their epidemiology. Between 2018 and 2020, broilers farms in northeastern Tunisia were monitored, and 39 clinically diseased flocks were sampled. Samples were screened for five viral and three bacterial respiratory pathogens using a panel of real-time PCR assays. The reemergence of H9N2 low pathogenic avian influenza virus (LPAIV) in commercial poultry was reported, and the Northern and Western African GI lineage strain was typed. The infectious bronchitis virus (IBV) GI-23 lineage and the avian metapneumovirus (aMPV) subtype B also were detected for the first time in broilers in Tunisia. H9N2 LPAIV was the most detected pathogen in the flocks tested, but rarely alone, as 15 of the 16 H9N2 positive flocks were co-infected. Except for infectious laryngotracheitis virus (ILTV), all of the targeted pathogens were detected, and in 61% of the respiratory disease cases, a combination of pathogens was identified. The major combinations were H9N2 + aMPV (8/39) and H9N2 + IBV (6/39), showing the high contribution of H9N2 LPAIV to the multifactorial respiratory diseases. This field survey provided evidence of the emergence of new respiratory viruses and the complexity of respiratory disease in Tunisia. A comprehensive and continuous surveillance strategy therefore is needed to better control respiratory pathogens in Tunisia.
Assuntos
Coinfecção , Vírus da Bronquite Infecciosa , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Doenças das Aves Domésticas , Infecções Respiratórias , Animais , Galinhas , Influenza Aviária/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Tunísia/epidemiologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/veterinária , Anticorpos Antivirais , Doenças das Aves Domésticas/epidemiologia , FilogeniaRESUMO
Avian influenza A(H5N8) virus has caused major epizootics in Europe since 2016. We conducted virologic analysis of aerosol and dust collected on poultry farms in France during 2020-2021. Our results suggest dust contributes to viral dispersal, even early in an outbreak, and could be a valuable surveillance tool.
Assuntos
Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Influenza Humana , Doenças das Aves Domésticas , Animais , Animais Selvagens , Aves , Surtos de Doenças/veterinária , Poeira , Fazendas , França/epidemiologia , Humanos , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/epidemiologiaRESUMO
Inclusion body hepatitis (IBH) is an economically important disease of chickens, with a worldwide distribution, caused by Fowl Aviadenoviruses (FAdVs). Currently, the increased number of cases, the virulence of the isolate strains, as well as the lack of cross-species protection highlight that detailed in-field data are fundamental for the development of successful control strategies. This case report provides a detailed clinicopathological investigation of an unusual IBH outbreak in a commercial broiler farm in the region of Macedonia, Greece. The farm consisted of 64,000 birds, originated from the same breeder stock and placed in three different houses (Flock A-C). At 20 days of age, a sudden increase in daily mortality was recorded in Flock A. It is worth mentioning that, although all flocks were serologically (indirect ELISA) and molecularly (RT-PCR) positive for FAdV, the mortality rate, attributed to IBH, was much higher in Flock A compared to others. The clinical manifestation included non-specific symptoms such as depression, inappetence, yellowish mucoid diarrhea, and lack of uniformity. At necropsy, typically, enlarged, pale, and friable livers were dominant, while sporadically lesions were recorded in the pancreas, kidneys, skeletal muscles, and lymphoid organs. The histopathological examination of liver samples showed multifocal inflammation, necrosis, and the presence of basophilic/ eosinophilic inclusion bodies in hepatocytes. In addition, the loss of the architecture of pancreatic lobules and the presence of fibrosis and foci of mononuclear cell aggregates were suggestive of chronic pancreatic inflammation. PCR analysis confirmed the presence of FAdV, belonging to species E, serotype FAdV-8b. Performance and financial calculations revealed that IBH increased Feed Conversion Ratio (FCR), feed cost/chick as well as feed cost/kg live weight, whereas the Livability (%) and the European Production Efficiency Factor (EPEF) were decreased in the most severely affected flocks (Flock A). This study is the first report of the detection and identification of FAdV serotypes associated with IBH in commercial broiler flocks in Greece. However, there is still a lack of information about the circulating FAdV serotypes in the country, and therefore epidemiological studies are needed to establish control strategies for IBH.
RESUMO
In late 2015, an epizootic of Highly Pathogenic Avian Influenza (H5Nx) was registered in Southwestern France, including more than 70 outbreaks in commercial poultry flocks. Phylogenetic analyses suggested local emergence of H5 viruses which differed from A/goose/Guangdong/1/1996 clade 2.3.4.4b lineage and shared a unique polybasic cleavage site in their hemagglutinin protein. The present work provides an overview of the pathobiological picture associated with this epizootic in naturally infected chickens, guinea fowls and ducks. Upon necropsy examination, selected tissues were sampled for histopathology, immunohistochemistry and quantitative Real Time Polymerase Chain Reaction. In Galliformes, HPAIVs infection manifested as severe acute systemic vasculitis and parenchymal necrosis and was associated with endothelial expression of viral antigen. In ducks, lesions were mild and infrequent, with sparse antigenic detection in respiratory and digestive mucosae and leukocytes. Tissue quantifications of viral antigen and RNA were higher in chickens and guinea fowls compared to duck. Subsequently, recombinant HA (rHA) was generated from a H5 HPAIV isolated from an infected duck to investigate its glycan-binding affinity for avian mucosae. Glycan-binding analysis revealed strong affinity of rHA for 3'Sialyl-LacNAc and low affinity for Sialyl-LewisX, consistent with a duck-adapted virus similar to A/Duck/Mongolia/54/2001 (H5N2). K222R and S227R mutations on rHA sequence shifted affinity towards Sialyl-LewisX and led to an increased affinity for chicken mucosa, confirming the involvement of these two mutations in the glycan-binding specificity of the HA. Interestingly, the rHA glycan binding pattern of guinea fowl appeared intermediate between duck and chicken. The present study presents a unique pathobiological description of the H5 HPAIVs outbreaks that occurred in 2015-2016 in Southwestern France.
Assuntos
Anseriformes , Galliformes , Vírus da Influenza A Subtipo H5N2 , Influenza Aviária , Animais , Anseriformes/metabolismo , Galinhas/metabolismo , Patos/metabolismo , Galliformes/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A Subtipo H5N2/genética , FilogeniaRESUMO
Horizontal gene transfer was long thought to be marginal in Mollicutes, but the capacity of some of these wall-less bacteria to exchange large chromosomal regions has been recently documented. Mycoplasma chromosomal transfer (MCT) is an unconventional mechanism that relies on the presence of a functional integrative conjugative element (ICE) in at least one partner and involves the horizontal acquisition of small and large chromosomal fragments from any part of the donor genome, which results in progenies composed of an infinite variety of mosaic genomes. The present study focuses on Mycoplasma bovis, an important pathogen of cattle responsible for major economic losses worldwide. By combining phylogenetic tree reconstructions and detailed comparative genome analyses of 36 isolates collected in Spain (2016 to 2018), we confirmed the mosaic nature of 16 field isolates and mapped chromosomal transfers exchanged between their hypothetical ancestors. This study provides evidence that MCT can take place in the field, most likely during coinfections by multiple strains. Because mobile genetic elements (MGEs) are classical contributors of genome plasticity, the presence of phages, insertion sequences (ISs), and ICEs was also investigated. Data revealed that these elements are widespread within the M. bovis species and evidenced classical horizontal transfer of phages and ICEs in addition to MCT. These events contribute to wide-genome diversity and reorganization within this species and may have a tremendous impact on diagnostic and disease control. IMPORTANCE Mycoplasma bovis is a major pathogen of cattle that has significant detrimental effects on economics and animal welfare in cattle rearing worldwide. Understanding the evolution and the adaptative potential of pathogenic mycoplasma species in the natural host is essential to combating them. In this study, we documented the occurrence of mycoplasma chromosomal transfer, an atypical mechanism of horizontal gene transfer, in field isolates of M. bovis that provide new insights into the evolution of this pathogenic species in their natural host. Although these events are expected to occur at low frequency, their impact is accountable for genome-wide variety and reorganization within M. bovis species, which may compromise both diagnostic and disease control.
Assuntos
Mycoplasma bovis , Tenericutes , Animais , Bovinos , Transferência Genética Horizontal , Mosaicismo , Mycoplasma bovis/genética , FilogeniaRESUMO
Recent outbreaks of highly pathogenic avian influenza in southwest France have raised questions regarding the role of commensal wild birds in the introduction and dissemination of pathogens between poultry farms. To assess possible infectious contacts at the wild-domestic bird interface, the presence of Mycoplasma gallisepticum (MG) was studied in the two sympatric compartments in southwest France. Among various peridomestic wild birds (n = 385), standard PCR primers targeting the 16S rRNA of MG showed a high apparent prevalence (up to 45%) in cloacal swabs of European starlings (Sturnus vulgaris, n = 108), while the MG-specific mgc2 gene was not detected. No tracheal swab of these birds tested positive, and no clinical sign was observed in positive birds, suggesting commensalism in the digestive tract of starlings. A mycoplasma strain was then isolated from a starling swab and its whole genome was sequenced using both Illumina and Nanopore technologies. Phylogenetic analysis showed that it was closely related to MG and M. tullyi, although it was a distinct species. A pair of specific PCR primers targeting the mgc2-like gene of this MG-like strain was designed and used to screen again the same avian populations and a wintering urban population of starlings (n = 50). Previous PCR results obtained in starlings were confirmed to be mostly due to this strain (20/22 positive pools). In contrast, the strain was not detected in fresh faeces of urban starlings. Furthermore, it was detected in one cloacal pool of white wagtails, suggesting infectious transmissions between synanthropic birds with similar feeding behaviour. As the new Starling mycoplasma was not detected in free-range ducks (n = 80) in close contact with positive starlings, nor in backyard (n = 320) and free-range commercial (n = 720) chickens of the area, it might not infect poultry. However, it could be involved in mycoplasma gene transfer in such multi-species contexts.
Assuntos
Infecções por Mycoplasma , Mycoplasma gallisepticum , Doenças das Aves Domésticas , Estorninhos , Animais , Animais Selvagens , Galinhas , Primers do DNA , Fazendas , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/genética , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , RNA Ribossômico 16S/genética , Estorninhos/genéticaRESUMO
Adenoviral pancreatitis has been amply described for decades in guinea fowl. Although its pathologic picture has been characterized fairly well, its etiology still remains only partially clarified. Based on several outbreaks diagnosed on commercial guinea flocks raised in France since 2017, we performed direct whole-genome sequencing from pancreatic lesional tissue by using the Oxford Nanopore Technologies (ONT) sequencing method. We generated 4781 viral reads and assembled a whole genome of 43,509 bp, clustering within fowl adenovirus type 1 (FAdV-1). A phylogenetic analysis based on a partial sequence of the hexon and short fiber genes on viruses collected in France showed 98.7% and 99.8% nucleotide identity, respectively. Altogether, these results confirm that an FAdV-1 closely related to chicken and other avian strains is the agent of pancreatitis in guinea fowl. This study illustrates the potential of ONT sequencing method to achieve rapid whole-genome sequencing directly from pathologic material.
Detección y tipificación de un adenovirus aviar tipo 1 (FAdV-1), agente de pancreatitis en gallinas de Guinea. La pancreatitis adenoviral se ha descrito ampliamente durante décadas en gallinas de Guinea. Aunque su cuadro patológico se ha caracterizado bastante bien, su etiología todavía permanece sólo parcialmente aclarada. Sobre la base de varios brotes diagnosticados en parvadas comerciales de guineas criadas en Francia desde el año 2017, se realizó una secuenciación directa del genoma completo a partir del tejido de la lesión pancreática mediante el método de secuenciación desarrollado por Oxford Nanopore Technologies. Se generaron 4781 lecturas virales y se ensambló un genoma completo de 43,509 pb, que se agrupó dentro del adenovirus aviar tipo 1 (FAdV-1). Un análisis filogenético basado en una secuencia parcial de los genes hexón y de fibra corta de virus recolectados en Francia mostró identidades de nucleótidos de 98.7% y 99.8%, respectivamente. En conjunto, estos resultados confirman que un adenovirus aviar tipo 1 estrechamente relacionado con el pollo y otras cepas aviares es el agente de la pancreatitis en la gallina de Guinea. Este estudio ilustra el potencial de las tecnologías desarrolladas por Oxford Nanopore Thechnologies para lograr una secuenciación rápida de todo el genoma directamente a partir de material patológico.
Assuntos
Infecções por Adenoviridae , Aviadenovirus , Adenovirus A das Aves , Pancreatite , Doenças das Aves Domésticas , Adenoviridae , Infecções por Adenoviridae/epidemiologia , Infecções por Adenoviridae/veterinária , Animais , Aviadenovirus/genética , Galinhas , Pancreatite/veterinária , FilogeniaRESUMO
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for COVID-19 and spread rapidly following its emergence in Wuhan in 2019. Although cats are, among other domestic animals, susceptible to SARS-CoV-2 infection, little is known about their epidemiological role in the dynamics of a household infection. In this study, we monitored five cats for viral shedding daily. Each cat was confined with its COVID-19 positive owners in separate households. Low loads of viral nucleic acid were found in two cats, but only one developed anti-SARS-CoV-2 antibodies, which suggests that cats have a limited role in COVID-19 epidemiology.
Assuntos
COVID-19/transmissão , COVID-19/veterinária , Doenças do Gato/transmissão , Doenças do Gato/virologia , Animais , Animais Domésticos , Anticorpos Neutralizantes , Doenças do Gato/epidemiologia , Gatos , Chlorocebus aethiops , Suscetibilidade a Doenças , Humanos , Masculino , Filogenia , SARS-CoV-2/classificação , SARS-CoV-2/genética , Células Vero , Zoonoses Virais/epidemiologia , Zoonoses Virais/transmissão , Eliminação de Partículas Virais , Sequenciamento Completo do GenomaRESUMO
Highly Pathogenic Avian Influenza viruses (HPAIVs) display a tissue pantropism, which implies a possible spread in feathers. HPAIV detection from feathers had been evaluated for H5N1 or H7N1 HPAIVs. It was suggested that viral RNA loads could be equivalent or higher in samples of immature feather compared to tracheal (TS) or cloacal swabs (CS). We investigated the suitability of feathers for the detection of clade 2.3.4.4b H5N8 HPAIV in ducks and geese field samples. In the six H5N8 positive flocks that were included in this study, TS, CS and immature wing feathers were taken from at least 10 birds. Molecular loads were then estimated using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) targetting H5 and M genes. In all flocks, viral loads were at least equivalent between feather and swab samples and in most cases up to 103 higher in feathers. Bayesian modelling confirmed that, in infected poultry, RT-qPCR was much more likely to be positive when applied on a feather sample only (estimated sensitivity between 0.89 and 0.96 depending on the positivity threshold) than on a combination of a tracheal and a cloacal swab (estimated sensitivity between 0.45 and 0.68 depending on the positivity threshold). Viral tropism and lesions in feathers were evaluated by histopathology and immunohistochemistry. Epithelial necrosis of immature feathers and follicles was observed concurrently with positive viral antigen detection and leukocytic infiltration of pulp. Accurate detection of clade 2.3.4.4b HPAIVs in feather samples were finally confirmed with experimental H5N8 infection on 10-week-old mule ducks, as viral loads at 3, 5 and 7 days post-infection were higher in feathers than in tracheal or cloacal swabs. However, feather samples were associated with lower viral loads than tracheal swabs at day 1, suggesting better detectability of the virus in feathers in the later course of infection. These results, based on both field cases and experimental infections, suggest that feather samples should be included in the toolbox of samples for detection of clade 2.3.4.4b HPAI viruses, at least in ducks and geese.
Assuntos
Patos , Gansos , Genótipo , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A Subtipo H5N8/fisiologia , Influenza Aviária/virologia , Tropismo Viral , Animais , Teorema de Bayes , Biópsia , França/epidemiologia , Imuno-Histoquímica , Influenza Aviária/diagnóstico , Influenza Aviária/epidemiologia , Doenças das Aves Domésticas/virologia , VirulênciaRESUMO
Highly pathogenic avian influenza A(H5N8) clade 2.3.4.4 spread in France during 2016-2017. We assessed the biosecurity and avian influenza virus infection status of 70 backyard flocks near H5N8-infected commercial farms. One flock was seropositive for clade 2.3.4.4. Backyard flocks linked to commercial farms had elevated risk for H5 infection.
Assuntos
Surtos de Doenças , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/transmissão , Influenza Aviária/virologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Animais , Aves , Ensaio de Imunoadsorção Enzimática , Fazendas , França , História do Século XXI , Influenza Aviária/epidemiologia , Influenza Aviária/história , Tipagem Molecular , Razão de Chances , Doenças das Aves Domésticas/epidemiologia , Estudos SoroepidemiológicosRESUMO
Avian pox is an infectious disease caused by avipoxviruses (APV), resulting in cutaneous and/or tracheal lesions. Poxviruses share large genome sizes (from 130 to 360â¯kb), featuring repetitions, deletions or insertions as a result of a long-term recombination history. The increasing performances of next-generation sequencing (NGS) opened new opportunities for surveillance of poxviruses, based on timely and affordable workflows. We investigated the application of the 3rd generation Oxford Nanopore Minion technology to achieve real-time whole-genome sequencing directly from lesions, without any enrichment or isolation step. Fowlpox lesions were sampled on hens, total DNA was extracted and processed for sequencing on a MinION, Oxford Nanopore. We readily generated whole APV genomes from cutaneous or tracheal lesions, without any isolation or PCR-based enrichment: Fowlpox virus reads loads ranged from 0.75% to 2.62% and reads up to 61â¯kbp were generated and readily assembled into 3 APV complete genomes. This long read size eases the assembly step and lowers the bioinformatics capacity requirements and processing time compared to huge sets of short reads. The complete genome analysis confirmed that these Fowlpox viruses cluster within clade A1 and host full length reticuloendotheliovirus (REV) inserts. The pathobiological relevance of REV insert, although a classical feature of fowlpoxviruses (FPVs), should be further investigated. Surveillance of emerging poxviruses could greatly benefit from real-time whole genome sequencing.
Assuntos
Avipoxvirus/classificação , Avipoxvirus/genética , Técnicas de Genotipagem/métodos , Doenças das Aves Domésticas/virologia , Infecções por Poxviridae/veterinária , Análise de Sequência de DNA/métodos , Sequenciamento Completo do Genoma/métodos , Animais , Avipoxvirus/isolamento & purificação , Galinhas , Monitoramento Epidemiológico , Epidemiologia Molecular/métodos , Nanoporos , Doenças das Aves Domésticas/epidemiologia , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/virologia , Fatores de TempoRESUMO
Respiratory syndromes (RS) are among the most significant pathological conditions in edible birds and are caused by complex coactions of pathogens and environmental factors. In poultry, low pathogenic avian influenza A viruses, metapneumoviruses, infectious bronchitis virus, infectious laryngotracheitis virus, Mycoplasma spp. Escherichia coli and/or Ornithobacterium rhinotracheale in turkeys are considered as key co-infectious agents of RS. Aspergillus sp., Pasteurella multocida, Avibacterium paragallinarum or Chlamydia psittaci may also be involved in respiratory outbreaks. An innovative quantitative PCR method, based on a nanofluidic technology, has the ability to screen up to 96 samples with 96 pathogen-specific PCR primers, at the same time, in one run of real-time quantitative PCR. This platform was used for the screening of avian respiratory pathogens: 15 respiratory agents, including viruses, bacteria and fungi potentially associated with respiratory infections of poultry, were targeted. Primers were designed and validated for SYBR green real-time quantitative PCR and subsequently validated on the Biomark high throughput PCR nanofluidic platform (Fluidigm©, San Francisco, CA, USA). As a clinical assessment, tracheal swabs were sampled from turkeys showing RS and submitted to this panel assay. Beside systematic detection of E. coli, avian metapneumovirus, Mycoplasma gallisepticum and Mycoplasma synoviae were frequently detected, with distinctive co-infection patterns between French and Moroccan flocks. This proof-of-concept study illustrates the potential of such panel assays for unveiling respiratory co-infection profiles in poultry.
Assuntos
Galinhas/microbiologia , Coinfecção/veterinária , Doenças das Aves Domésticas/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Infecções Respiratórias/veterinária , Perus/microbiologia , Animais , Primers do DNA/genética , Ensaios de Triagem em Larga Escala , Aves Domésticas , Doenças das Aves Domésticas/microbiologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/microbiologiaRESUMO
Recent in-depth genetic analyses of influenza A virus samples have revealed patterns of intra-host viral genetic variability in a variety of relevant systems. These have included laboratory infected poultry, horses, pigs, chicken eggs and swine respiratory cells, as well as naturally infected poultry and horses. In humans, next generation sequencing techniques have enabled the study of genetic variability at specific positions of the viral genome. The present study investigated how 454 pyrosequencing could help unravel intra-host genetic diversity patterns on the full-length viral hæmagglutinin and neuraminidase genes from human H1N1 (2009) pandemic influenza clinical cases. This approach revealed unexpected patterns of co-infection in a 3-week old toddler, arising from rapid and complex reassortment phenomena on a local epidemiological scale. It also suggested the possible existence of very low frequency mutants resistant to neuraminidase inhibitors in two untreated patients. As well as revealing patterns of intra-host viral variability, this report highlights technical challenges in the appraisal of scientifically and medically relevant topics such as the natural occurrence of homologous recombination or very low frequency drug-resistant variants in influenza virus populations.