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2.
Arch Virol ; 165(1): 87-96, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707455

RESUMO

In May 2017, high mortality of chickens and Muscovy ducks due to the H5N8 highly pathogenic avian influenza virus (HPAIV) was reported in the Democratic Republic of Congo (DR Congo). In this study, we assessed the molecular, antigenic, and pathogenic features in poultry of the H5N8 HPAIV from the 2017 Congolese outbreaks. Phylogenetic analysis of the eight viral gene segments revealed that all 12 DR Congo isolates clustered in clade 2.3.4.4B together with other H5N8 HPAIVs isolated in Africa and Eurasia, suggesting a possible common origin of these viruses. Antigenically, a slight difference was observed between the Congolese isolates and a representative virus from group C in the same clade. After intranasal inoculation with a representative DR Congo virus, high pathogenicity was observed in chickens and Muscovy ducks but not in Pekin ducks. Viral replication was higher in chickens than in Muscovy duck and Pekin duck organs; however, neurotropism was pronounced in Muscovy ducks. Our data confirmed the high pathogenicity of the DR Congo virus in chickens and Muscovy ducks, as observed in the field. National awareness and strengthening surveillance in the region are needed to better control HPAIVs.


Assuntos
Antígenos Virais/metabolismo , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A Subtipo H5N8/patogenicidade , Influenza Aviária/imunologia , Doenças das Aves Domésticas/virologia , África , Animais , Ásia , Galinhas , República Democrática do Congo , Patos/classificação , Patos/virologia , Europa (Continente) , Sequenciamento de Nucleotídeos em Larga Escala , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A Subtipo H5N8/isolamento & purificação , Influenza Aviária/virologia , Filogenia , Filogeografia , Doenças das Aves Domésticas/imunologia , Especificidade da Espécie , Replicação Viral
3.
Emerg Microbes Infect ; 8(1): 1535-1545, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31661383

RESUMO

Influenza A virus infections occur in different species, causing mild to severe respiratory symptoms that lead to a heavy disease burden. Eurasian avian-like swine influenza A(H1N1) viruses (EAS-H1N1) are predominant in pigs and occasionally infect humans. An influenza A(H1N1) virus was isolated from a boy who was suffering from fever and headache and designated as A/Tianjin-baodi/1606/2018(H1N1). Full-genome sequencing and phylogenetic analysis revealed that A/Tianjin-baodi/1606/2018(H1N1) is a novel reassortant EAS-H1N1 containing gene segments from EAS-H1N1 (HA and NA), classical swine H1N1(NS) and A(H1N1)pdm09(PB2, PB2, PA, NP and M) viruses. The isolation and analysis of A/Tianjin-baodi/1606/2018(H1) provide further evidence that EAS-H1N1 poses a threat to human health and greater attention should be paid to surveillance of influenza virus infection in pigs and humans.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Criança , China , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Influenza Aviária/virologia , Masculino , Infecções por Orthomyxoviridae/virologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/virologia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Suínos
4.
Zhonghua Jie He He Hu Xi Za Zhi ; 42(10): 750-754, 2019 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-31594108

RESUMO

Objective: To analyzed the clinical characteristics and prognosis of patients with H7N9 avian influenza. Methods: The baseline characteristics, clinical manifestations, treatments, laboratory and imaging findings were collected and analyzed for 20 patients with H7N9 avian influenza admitted to the First Affiliated Hospital of Nanchang University from December 2016 to March 2017. According to the final clinical outcome, the patients were divided into the death group and the survival group. Ten patients in the death group died, and 10 patients in the survival group were discharged. The data with normal distribution were analyzed by t test. The data with non-normal distribution were analyzed by Wilcoxon rank sum test. Results: Of the 20 patients, 13 were males and 7 were females, aging 40-82 years, with a mean age of (60±12) years. Twelve patients had a definite history of poultry exposure and 10 had chronic underlying diseases such as hypertension and diabetes. The clinical manifestations were mainly fever, cough, hemoptysis, respiratory distress, fatigue, etc. In the survival group, the platelet count was(167-315)×10(9)/L, while it was (78-152)×10(9)/L in the death group. The average white blood cell count was (7.78-11.52)×10(9)/L and (9.91-15.93)×10(9)/L in the survival and death groups respectively. The average value of lymphocyte count was (0.69-1.59)×10(9)/L and (0.58-0.86)×10(9)/L in the survival and death groups respectively. In the death group the glutamic-pyruvic transaminase (ALT) value was (14.0-352.0) U/L, the total bilirubin value was (6.9-34.5) µmol/L, the creatine kinase MB (CK-MB) was (16.0-162.0) U/L, the serum calcium value was (1.4-2.0) mmol/L, the C-reactive protein value was (33.1-414.0) mg/L, and the calcium reduction prime value was (0.6-100.0) µg/L. In the survival group,the ALT value was (25.0-181.0) U/L, the total bilirubin value was (4.8-25.9) µmol/L, the CK-MB value was (15.0-40.0) U/L, the serum calcium value was (1.9-2.4) mmol/L, the C-reaction protein value was (12.8-52.5) mg/L, and the procalcitonin value was (0.3-23.3) µg/L. Sixteen cases suffered severe pneumonia. Twelve patients received extracorporeal membrane oxygenation (ECMO), and 4 survived. The cause of death was mainly related to factors such as age, chronic underlying diseases and severity of illness. Conclusions: Human infection with H7N9 avian influenza virus was highly pathogenic, and prone to progress into severe pneumonia, with a high mortality. Decreased platelet count was associated with mortality (t=4.07, P=0.001), predictive of patient outcome.


Assuntos
Antivirais/uso terapêutico , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/tratamento farmacológico , Síndrome do Desconforto Respiratório do Adulto/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Aves , China/epidemiologia , Tosse/etiologia , Diabetes Mellitus/epidemiologia , Exposição Ambiental , Feminino , Febre/etiologia , Humanos , Hipertensão/epidemiologia , Influenza Aviária , Influenza Humana/epidemiologia , Influenza Humana/mortalidade , Masculino , Pessoa de Meia-Idade , Pneumonia/epidemiologia , Pneumonia/etiologia , Pneumonia/virologia , Prognóstico , Resultado do Tratamento
5.
Vet Microbiol ; 237: 108381, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31585646

RESUMO

The H5N8 highly pathogenic avian influenza viruses (HPAIVs) isolated in Japan during the 2014-2015 winter differed in their pathogenicity in chickens. In the present study, we examined the possibility that a comparatively less pathogenic strain was first brought into the country by migratory birds, and then acquired enhanced pathogenicity by infecting chicken flocks. We showed that the A/tundra swan/Tottori/C6nk/2014 (H5N8) (Tottori P0) strain required 10 days to kill all chickens via the intranasal route. However, Tottori P1-B, a strain recovered from the brain of a chicken infected with parental Tottori P0, showed enhanced pathogenicity; Tottori P1-B replicated significantly in the lung and liver, and killed all infected birds within 6 days, which was comparable to a chicken farm isolate obtained in the same season, A/environment/Miyazaki/11/2014 (H5N8). Tottori P1-B showed more marked proliferation in MDCK and chicken fibroblast cells, especially during the early phase of infection. Sequence analysis revealed a single mutation, M374 V, in nucleoprotein (NP) of the passaged virus, and this substitution was conserved after a further inoculation study. Position 374 in NP is located in the functional domain interacting with polymerase protein, PB2, indicating that viral polymerase activity was involved in the rapid growth of Tottori P1-B in vitro and in vivo. These results suggest that HPAIV, which originally had comparatively low pathogenicity to chickens, can increase its pathogenicity through the infection from migratory birds to domestic chickens.


Assuntos
Galinhas , Patos , Vírus da Influenza A Subtipo H5N8/patogenicidade , Influenza Aviária/virologia , Animais , Linhagem Celular , Embrião de Galinha , Cães , Fibroblastos/virologia , Modelos Moleculares , Conformação Proteica , Proteínas Virais/genética , Proteínas Virais/metabolismo , Virulência
6.
Emerg Microbes Infect ; 8(1): 1465-1478, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608791

RESUMO

The ANP32A is responsible for mammalian-restricted influenza virus polymerase activity. However, the mechanism of ANP32A modulation of polymerase activity remains poorly understood. Here, we report that chicken ANP32A (chANP32A) -X1 and -X2 stimulated mammalian-restricted PB2 627E polymerase activity in a dose-dependent manner. Distinct effects of ANP32A constructs suggested that the 180VK181 residues within chANP32A-X1 are necessary but not sufficient to stimulate PB2 627E polymerase activity. The PB2 N567D, T598V, A613V or F636L mutations promoted PB2 627E polymerase activity and chANP32A-X1 showed additive effects, providing further support that species-specific regulation of ANP32A might be only relevant with the PB2 E627K mutation. Rescue of cycloheximide-mediated inhibition showed that ANP32A is species-specific for modulation of vRNA but not mRNA and cRNA, demonstrating chANP32A-X1 compensated for defective cRNPs produced by PB2 627E virus in mammalian cells. The promoter mutations of cRNA enhanced the restriction of PB2 627E polymerase in mammalian cells, which could be restored by chANP32A-X1, indicating that ANP32A is likely to regulate the interaction of viral polymerase with RNA promoter. Coimmunoprecipitation showed that ANP32A did not affect the primary cRNPs assembly. We propose a model that chANP32A-X1 regulates PB2 627E polymerase for suitable interaction with cRNA promoter for vRNA replication.


Assuntos
Vírus da Influenza A Subtipo H1N1/enzimologia , Subtipo H7N9 do Vírus da Influenza A/enzimologia , Vírus da Influenza A Subtipo H9N2/enzimologia , Influenza Aviária/metabolismo , Influenza Humana/metabolismo , Doenças das Aves Domésticas/metabolismo , RNA Replicase/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Galinhas , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/genética , Influenza Aviária/virologia , Influenza Humana/genética , Influenza Humana/virologia , Mutação , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/virologia , Ligação Proteica , RNA Replicase/genética , RNA Viral/genética , RNA Viral/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Alinhamento de Sequência , Especificidade da Espécie , Proteínas Virais/genética , Replicação Viral
7.
Infect Immun ; 88(1)2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31591166

RESUMO

The avian pathogen Mycoplasma gallisepticum, the etiological agent of chronic respiratory disease in chickens, exhibits enhanced pathogenesis in the presence of a copathogen such as low-pathogenic avian influenza virus (LPAIV). To further investigate the intricacies of this copathogenesis, chickens were monoinfected or coinfected with either virulent M. gallisepticum strain Rlow or LPAIV H3N8 (A/duck/Ukraine/1963), with assessment of tracheal histopathology, pathogen load, and transcriptomic host responses to infection by RNA sequencing. Chickens coinfected with M. gallisepticum Rlow followed by LPAIV H3N8 exhibited significantly more severe tracheal lesions and mucosal thickening than chickens infected with LPAIV H3N8 alone and greater viral loads than chickens infected first with H3N8 and subsequently with M. gallisepticum Rlow Recovery of live M. gallisepticum was significantly higher in chickens infected first with LPAIV H3N8 and then with M. gallisepticum Rlow, compared to chickens given a mock infection followed by M. gallisepticum Rlow The transcriptional responses to monoinfection and coinfection with M. gallisepticum and LPAIV highlighted the involvement of differential expression of genes such as Toll-like receptor 15, Toll-like receptor 21, and matrix metallopeptidase 1. Pathway and gene ontology analyses of these differentially expressed genes suggest that coinfection with virulent M. gallisepticum and LPAIV induces decreases in the expression of genes related to ciliary activity in vivo and alters multiple immune-related signaling cascades. These data aid in the understanding of the relationship between M. gallisepticum and LPAIV during copathogenesis in the natural host and may contribute to further understanding of copathogen infections of humans and other animals.


Assuntos
Coinfecção/patologia , Influenza Aviária/patologia , Infecções por Mycoplasma/patologia , Doenças das Aves Domésticas/patologia , Traqueia/patologia , Animais , Carga Bacteriana , Galinhas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Histocitoquímica , Interações Hospedeiro-Patógeno , Vírus da Influenza A/crescimento & desenvolvimento , Influenza Aviária/complicações , Infecções por Mycoplasma/complicações , Mycoplasma gallisepticum/crescimento & desenvolvimento , Carga Viral
8.
Int J Nanomedicine ; 14: 7533-7548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571862

RESUMO

Background: The influenza A virus (IAV) is known for its high variability and poses a huge threat to the health of humans and animals. Pigs play a central role in the cross-species reassortment of IAV. Ectodomain of matrix protein 2 (M2e) is the most conserved protective antigen in IAV and can be used to develop nanovaccines through nanoparticles displaying to increase its immunogenicity. However, the high immunogenicity of nanoparticles can cause the risk of off-target immune response, and excess unwanted antibodies may interfere with the protective efficacy of M2e-specific antibodies. Therefore, it is necessary to select reasonable nanoparticles to make full use of antibodies against nanoparticles while increasing the level of M2e-specific antibodies. Porcine circovirus type 2 (PCV2) is the most susceptible virus in pigs and can promote IAV infection. It is meaningful to develop a vaccine that can simultaneously control swine influenza virus (SIV) and PCV2. Methods: In the present study, M2e of different copy numbers were inserted into the capsid (Cap) protein of PCV2 and expressed in Escherichia coli to form self-assembled chimeric virus-like particles (VLPs) nanovaccine. BALB/c mice and pigs were immunized with these nanovaccines to explore optimal anti-IAV and anti-PCV2 immunity. Results: Cap is capable of carrying at least 81 amino acid residues (three copies of M2e) at its C-terminal without impairing VLPs formation. Cap-3M2e VLPs induced the highest levels of M2e-specific immune responses, conferring protection against lethal challenge of IAVs from different species and induced specific immune responses consistent with PCV2 commercial vaccines in mice. In addition, Cap-3M2e VLPs induced high levels of M2e-specific antibodies and PCV2-specific neutralizing antibodies in pigs. Conclusion: Cap-3M2e VLP is an economical and promising bivalent nanovaccine, which provides dual protection against IAV and PCV2.


Assuntos
Circovirus/imunologia , Vírus da Influenza A/imunologia , Nanopartículas/uso terapêutico , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Aves/virologia , Proteínas do Capsídeo/química , Proliferação de Células , Citocinas/metabolismo , Cães , Feminino , Humanos , Imunidade Humoral , Influenza Aviária/imunologia , Influenza Aviária/prevenção & controle , Influenza Aviária/virologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Linfócitos/citologia , Células Madin Darby de Rim Canino , Camundongos Endogâmicos BALB C , Testes de Neutralização , Proteínas Recombinantes/isolamento & purificação , Suínos , Vírion/imunologia , Vírion/ultraestrutura
9.
Rev Sci Tech ; 38(1): 225-237, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31564728

RESUMO

In 2016-2017, the H5N8 strain of highly pathogenic avian influenza (HPAI) spread worldwide and Uganda reported the first occurrence of the disease in its poultry and wild birds. Genetic analysis revealed that the virus clusters with 2.3.4.4 group B strains from birds in central and southern Asia, and thus forms part of the 2.3.4.4 group B clade. Since Uganda is in the path of two major migratory bird flyways, it is likely that infected migratory wild birds played a crucial role in the introduction of H5N8 HPAI viruses into Uganda. The outbreaks happened in the districts of Wakiso, Masaka and Kalangala and affected domestic and wild birds. A One Health Multisectoral Coordination Committee, consisting of a National Task Force, Technical Working Groups and District Disaster Management Committees, was immediately activated to coordinate the preparedness and response efforts to control the disease. In all the affected districts, surveillance was intensified on both domestic and wild birds; biosecurity measures were increased; and movement controls, culling, cleaning, disinfection and safe disposal of carcasses were implemented. Awareness of the disease was raised through education materials, leaflets and brochures distributed to farmers. Finally, Uganda successfully controlled the H5N8 outbreak, using its national preparedness and response mechanisms and through collaboration with international partners. The emergence and spread of this virus strain in Uganda and other parts of Africa poses a significant threat to the poultry industry and food security.


Assuntos
Animais Selvagens , Surtos de Doenças , Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Migração Animal , Animais , Ásia , Aves , Surtos de Doenças/prevenção & controle , Humanos , Influenza Aviária/prevenção & controle , Uganda
10.
J Vet Sci ; 20(5): e56, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31565899

RESUMO

Korea is located within the East Asian-Australian flyway of wild migratory birds during the fall and winter seasons. Consequently, the likelihood of introduction of numerous subtypes and pathotypes of the Avian influenza (AI) virus to Korea has been thought to be very high. In the current study, we surveyed wild bird feces for the presence of AI virus that had been introduced to Korea between September 2017 and February 2018. To identify and characterize the AI virus, we employed commonly used methods, namely, virus isolation (VI) via egg inoculation, real-time reverse transcription-polymerase chain reaction (rRT-PCR), conventional RT-PCR (cRT-PCR) and a newly developed next generation sequencing (NGS) approach. In this study, 124 out of 11,145 fresh samples of wild migratory birds tested were rRT-PCR positive; only 52.0% of VI positive samples were determined as positive by rRT-PCR from fecal supernatant. Fifty AI virus specimens were isolated from fresh fecal samples and typed. The cRT-PCR subtyping results mostly coincided with the NGS results, although NGS detected the presence of 11 HA genes and four NA genes that were not detected by cRT-PCR. NGS analysis confirmed that 12% of the identified viruses were mixed-subtypes which were not detected by cRT-PCR. Prevention of the occurrence of AI virus requires a workflow for rapid and accurate virus detection and verification. However, conventional methods of detection have some limitations. Therefore, different methods should be combined for optimal surveillance, and further studies are needed in aspect of the introduction and application of new methods such as NGS.


Assuntos
Aves , Monitoramento Epidemiológico/veterinária , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Animais , Animais Selvagens , Influenza Aviária/virologia , Vigilância da População/métodos , Prevalência , República da Coreia/epidemiologia
13.
Biochimie ; 166: 203-213, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31518617

RESUMO

Influenza A virus (IAV) is one of the most common infectious pathogen and associated with significant morbidity and mortality. Although processing the IAV hemagglutinin (HA) envelope glycoprotein precursor is a pre-requisite for viral membrane fusion activity, viral entry and transmission, HA-processing protease is not encoded in the IAV genome and thus the cellular trypsin-type serine HA-processing proteases determine viral infectious tropism and viral pathogenicity. The initial process of IAV infection of the airway is followed by marked upregulation of ectopic trypsin in various organs and endothelial cells through the induction of various proinflammatory cytokines, and this process has been termed the "influenza virus-cytokine-trypsin" cycle. In the advanced stage of IAV infection, the cytokine storm induces disorders of glucose and lipid metabolism and the "metabolic disorders-cytokine" cycle is then linked with the "influenza virus-cytokine-trypsin" cycle, to advance the pathogenic process into energy crisis and multiple organ failure. Application of protease inhibitors and treatment of metabolic disorders that break these cycles and their interconnection is therefore a promising therapeutic approach against influenza. This review discusses IAV pathogenicity on trypsin type serine HA-processing proteases, cytokines, metabolites and therapeutic options.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A , Influenza Humana , Serina Proteases/fisiologia , Internalização do Vírus/efeitos dos fármacos , Animais , Galinhas/virologia , Citocinas/metabolismo , Humanos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/patogenicidade , Influenza Aviária/tratamento farmacológico , Influenza Aviária/virologia , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Orthomyxoviridae/efeitos dos fármacos , Orthomyxoviridae/patogenicidade , Tripsina/metabolismo
14.
Acta Biochim Pol ; 66(3): 329-336, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31531422

RESUMO

The potential emergence of deadly pandemic influenza viruses is unpredictable and most have emerged with no forewarning. The distinct epidemiological and pathological patterns of the Spanish (H1N1), pandemic-2009 (H1N1), and avian influenza (H5N1), known as bird flu, viruses may allow us to develop a 'template' for possible emergence of devastating pandemic strains. Here, we provide a detailed molecular dissection of the structural and nonstructural proteins of this triad of viruses. GenBank data for three representative strains were analyzed to determine the polymorphic amino acids, genetic distances, and isoelectric points, hydrophobicity plot, and protein modeling of various proteins. We propose that the most devastating pandemic strains may have full-length PB1-F2 protein with unique residues, highly cleavable HA, and a basic NS1. Any newly emerging strain should be compared with these three strains, so that resources can be directed appropriately.


Assuntos
Simulação por Computador , Vírus da Influenza A Subtipo H1N1/genética , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Proteínas Virais/química , Animais , Aves , Transmissão de Doença Infecciosa , Genoma Viral , Humanos , Influenza Pandêmica, 1918-1919 , Vacinas contra Influenza , Influenza Aviária/epidemiologia , Influenza Aviária/prevenção & controle , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias , Conformação Proteica em alfa-Hélice , Proteínas Virais/genética
15.
Mol Immunol ; 114: 497-512, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31518854

RESUMO

Compounding with the problem of frequent antigenic shift and occasional drift of the segmented genome of Avian Influenza Virus (AIV), vaccines based on major surface glycoproteins such as haemagglutinin (HA) to counter heterosubtypic AIV infection in chickens remain unsuccessful. In contrast, neuraminidase (NA), the second most abundant surface glycoprotein present in viral capsid is less mutable and, in some instances, successful in eliciting inter-species cross-reactive antibody responses. However, without selective activation of B-cells and T-cells, the ability of NA to induce strong cell mediated immune responses is limited, thus NA based vaccines cannot singularly address the risk of virus escape from host defence. To this end, the highly conserved ectodomain of influenza matrix protein-2 (M2e) has emerged as an attractive cross-protective vaccine target. The present study describes the potential of recombinant Lactococcus lactis (rL. lactis) in expressing functional influenza NA or M2e proteins and conferring effective mucosal and systemic immune responses in the intestine as well as in the upper respiratory airways (trachea) of chickens. In addition, lavages collected from trachea and intestine of birds administered with rL. lactis expressing influenza NA or M2e protein were found to protect MDCK cells against avian influenza type A/PR/8/34 (H1N1) virus challenge. Although minor, the differences in the expression of pro-inflammatory cytokines gene transcripts targeted in this study among the birds administered with either empty or rL. lactis could be attributed to the activation of innate response by L. lactis.


Assuntos
Galinhas/imunologia , Imunidade nas Mucosas/imunologia , Influenza Aviária/imunologia , Lactococcus lactis/imunologia , Neuraminidase/imunologia , Proteínas da Matriz Viral/imunologia , Animais , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Galinhas/virologia , Reações Cruzadas/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Linfócitos T/imunologia , Vacinação/métodos
16.
Emerg Microbes Infect ; 8(1): 1280-1290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31495283

RESUMO

The H3N2 influenza viruses became widespread in humans during the 1968 H3N2 pandemic and have been a major cause of influenza epidemics ever since. Different lineages of H3N2 influenza viruses are also commonly found in animals. If a different lineage of H3N2 virus jumps to humans, a human influenza pandemic could occur with devastating consequences. Here, we studied the genetics, receptor-binding properties, and replication and transmission in mammals of 15 H3N2 avian influenza viruses detected in live poultry markets in China. We found that the H3N2 avian influenza viruses are complicated reassortants with distinct replication phenotypes in mice. Five viruses replicated efficiently in mice and bound to both human-type and avian-type receptors. These viruses transmitted efficiently to direct-contact guinea pigs, and three of them also transmitted among guinea pigs and ferrets via respiratory droplets. Moreover, ferret antiserum induced by human H3N2 viruses did not react with any of the H3N2 avian influenza viruses. Our study demonstrates that the H3N2 avian influenza viruses pose a clear threat to human health and emphasizes the need for continued surveillance and evaluation of the H3N2 influenza viruses circulating in nature.


Assuntos
Transmissão de Doença Infecciosa , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/fisiologia , Influenza Aviária/virologia , Aves Domésticas/virologia , Ligação Viral , Animais , China , Modelos Animais de Doenças , Furões , Cobaias , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Camundongos Endogâmicos BALB C , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Vírus Reordenados/fisiologia , Receptores Virais/metabolismo , Doenças dos Roedores/virologia , Replicação Viral
17.
Biosens Bioelectron ; 143: 111632, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31479987

RESUMO

We present a sunlight based handheld smartphone spectrometer. The device first gathers the sunlight to pass through the sample, and then the transmitted light illuminates on a grating to generate spectrum finally recorded by the smartphone monochrome camera. All the optical elements are assembled with the smartphone to integrate a handheld device with the size of 140.2 mm × 67.4 mm × 80.5 mm. Besides, a smartphone application is also developed for automatic spectral calibration, detection, analysis and display. Compared to the white light emitting diode and the halogen lamp, the sunlight has more uniform distribution covering the entire visible spectral range; and the proposed device also avoids the bulky sizes of those broadband light sources. Additionally, the monochrome camera is used instead of the color camera not only to pursue a high spectral resolution as 0.276 nm/pixel but also to avoid the color overlapping. We demonstrate the device capability on detecting avian influenza virus H7N9 and porcine circovirus type 2 antibodies, proving the device has rather high sensitivity similar to the commercial microplate reader. Considering its advantages as compact size, high spectral resolution and detecting sensitivity, it is believed the proposed sunlight based handheld smartphone spectrometer is potential to be broadly applied in on-site detections.


Assuntos
Técnicas Biossensoriais , Circovirus/isolamento & purificação , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Smartphone , Animais , Aves/virologia , Circovirus/patogenicidade , Colorimetria , Humanos , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Influenza Aviária/diagnóstico , Influenza Aviária/virologia , Refratometria , Análise Espectral , Luz Solar , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia
18.
BMC Infect Dis ; 19(1): 762, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477028

RESUMO

BACKGROUND: Avian influenza A (H5N6) virus poses a great threat to the human health since it is capable to cross the species barrier and infect humans. Although human infections are believed to largely originate from poultry contaminations, the transmissibility is unclear and only limited information was available on poultry environment contaminations, especially in Fujian Province. METHODS: A total of 4901 environmental samples were collected and tested for Avian Influenza Virus (AIV) from six cities in Fujian Province through the Fujian Influenza Surveillance System from 2013 to 2017. Two patient-related samples were taken from Fujian's first confirmed H5N6 human case and his backyard chicken feces in 2017. Chi-square test or Fisher's exact probability test was used to compare the AIV and the viral subtype positive rates among samples from different Surveillance cities, surveillance sites, sample types, and seasons. Phylogenetic tree analysis and molecular analysis were conducted to track the viral transmission route of the human infection and to map out the evolutions of H5N6 in Fujian. RESULTS: The overall positive rate of the H5 subtype AIVs was 4.24% (208/4903). There were distinctive differences (p < 0.05) in the positive rates in samples from different cities, sample sites, sample types and seasons. The viruses from the patient and his backyard chicken feces shared high homologies (99.9-100%) in all the eight gene segments. Phylogenetic trees also showed that these two H5N6 viruses were closely related to each other, and were classified into the same genetic clade 2.3.4.4 with another six H5N6 isolates from the environmental samples. The patient's H5N6 virus carried genes from H6N6, H5N8 and H5N6 viruses originated from different areas. The R294K or N294S substitution was not detected in the neuraminidase (NA). The S31 N substitution in the matrix2 (M2) gene was detected but only in one strain from the environmental samples. CONCLUSIONS: The H5 subtype of AIVs has started circulating in the poultry environments in Fujian Province. The patient's viral strain originated from the chicken feces in his backyard. Genetic reassortment in H5N6 viruses in Fujian Province was indicated. The H5N6 viruses currently circulating in Fujian Province were still commonly sensitive to Oseltamivir and Zanamivir, but the resistance against Amantadine has emerged.


Assuntos
Vírus da Influenza A/isolamento & purificação , Influenza Aviária/virologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Infecções por Orthomyxoviridae/virologia , Aves Domésticas/virologia , Animais , Embrião de Galinha , Galinhas/virologia , China/epidemiologia , Patos/virologia , Meio Ambiente , Microbiologia Ambiental , Genes Virais , Abrigo para Animais/normas , Humanos , Vírus da Influenza A/genética , Influenza Aviária/diagnóstico , Influenza Aviária/epidemiologia , Tipagem Molecular , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Filogenia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Fatores de Risco
19.
Vet Microbiol ; 235: 234-242, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383307

RESUMO

During 2012-2015, six H5N1 avian influenza viruses were isolated from domestic birds and the environment around Qinghai Lake. Phylogenetic analysis of HA genes revealed that A/chicken/Gansu/XG2/2012 (CK/GS/XG2/12) belonged to clade 2.3.2.1a, while A/environment/Qinghai/1/2013 (EN/QH/1/13), A/chicken/Qinghai/QH1/2015 (CK/QH/QH1/15), A/chicken/Qinghai/QH2/2015 (CK/QH/QH2/15), A/chicken/Qinghai/QH3/2015 (CK/QH/QH3/15), and A/goose/Qinghai/QH6/2015 (GS/QH/QH6/15) belonged to clade 2.3.2.1c. Further analysis of the internal genes of the isolates found that the PB2 gene of EN/QH/1/13 had 99.6% nucleotide identity with that of A/tiger/Jiangsu/1/2013 (H5N1), which clustered into an independent branch with PB2 from multiple subtypes. PB2, PB1, and M genes of CK/QH/QH3/15 were from H9N2, suggesting it was a reassortant of H5N1 and H9N2. Animal studies of three selected viruses revealed that CK/GS/XG2/12, EN/QH/1/13, and CK/QH/QH3/15 were highly lethal to chickens, with intravenous pathogenicity indexes (IVPIs) of 2.97, 2.81, and 3.00, respectively, and systemically replicated in chickens. In a mouse study, three selected H5N1 viruses were highly pathogenic to mice and readily replicated in the lungs, nasal turbinates, kidneys, spleens, and brains. Therefore, isolates in this study appear to be novel reassortants that were circulating at the interface of wild and domestic birds around Qinghai Lake and are lethal to chickens and mice. These data suggest that more extensive surveillance should be implemented, and matched vaccines should be chosen for the domestic birds in this area.


Assuntos
Animais Domésticos/virologia , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/epidemiologia , Lagos/virologia , Células A549 , Animais , Galinhas/virologia , China/epidemiologia , Cães , Patos/virologia , Evolução Molecular , Feminino , Humanos , Virus da Influenza A Subtipo H5N1/patogenicidade , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/mortalidade , Influenza Aviária/virologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Vírus Reordenados/genética , Vírus Reordenados/patogenicidade , Replicação Viral
20.
PLoS Comput Biol ; 15(8): e1007189, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31386651

RESUMO

Model-based phylodynamic approaches recently employed generalized linear models (GLMs) to uncover potential predictors of viral spread. Very recently some of these models have allowed both the predictors and their coefficients to be time-dependent. However, these studies mainly focused on predictors that are assumed to be constant through time. Here we inferred the phylodynamics of avian influenza A virus H9N2 isolated in 12 Asian countries and regions under both discrete trait analysis (DTA) and structured coalescent (MASCOT) approaches. Using MASCOT we applied a new time-dependent GLM to uncover the underlying factors behind H9N2 spread. We curated a rich set of time-series predictors including annual international live poultry trade and national poultry production figures. This time-dependent phylodynamic prediction model was compared to commonly employed time-independent alternatives. Additionally the time-dependent MASCOT model allowed for the estimation of viral effective sub-population sizes and their changes through time, and these effective population dynamics within each country were predicted by a GLM. International annual poultry trade is a strongly supported predictor of virus migration rates. There was also strong support for geographic proximity as a predictor of migration rate in all GLMs investigated. In time-dependent MASCOT models, national poultry production was also identified as a predictor of virus genetic diversity through time and this signal was obvious in mainland China. Our application of a recently introduced time-dependent GLM predictors integrated rich time-series data in Bayesian phylodynamic prediction. We demonstrated the contribution of poultry trade and geographic proximity (potentially unheralded wild bird movements) to avian influenza spread in Asia. To gain a better understanding of the drivers of H9N2 spread, we suggest increased surveillance of the H9N2 virus in countries that are currently under-sampled as well as in wild bird populations in the most affected countries.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária/transmissão , Modelos Biológicos , Migração Animal , Animais , Animais Selvagens/virologia , Ásia/epidemiologia , Teorema de Bayes , Aves/virologia , Comércio , Biologia Computacional , Monitoramento Ambiental , Vírus da Influenza A Subtipo H9N2/classificação , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Modelos Lineares , Filogeografia/estatística & dados numéricos , Dinâmica Populacional , Aves Domésticas/virologia , Análise Espaço-Temporal
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