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1.
Viruses ; 13(2)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498495

RESUMO

Newcastle disease (ND) is a highly transmissible and devastating disease that affects poultry and wild birds worldwide. Comprehensive knowledge regarding the characteristics and epidemiological factors of the ND virus (NDV) is critical for the control and prevention of ND. Effective vaccinations can prevent and control the spread of the NDV in poultry populations. For decades, the Democratic Republic of the Congo (DRC) has reported the impacts of ND on commercial and traditional poultry farming systems. The reports were preliminary clinical observations, and few cases were confirmed in the laboratory. However, data on the phylogenetic, genetic, and virological characteristics of NDVs circulating in the DRC are not available. In this study, the whole-genome sequences of three NDV isolates obtained using the next-generation sequencing method revealed two isolates that were a new variant of NDV, and one isolate that was clustered in the subgenotype VII.2. All DRC isolates were velogenic and were antigenically closely related to the vaccine strains. Our findings reveal that despite the circulation of the new variant, ND can be controlled in the DRC using the current vaccine. However, epidemiological studies should be conducted to elucidate the endemicity of the disease so that better control strategies can be implemented.


Assuntos
Doença de Newcastle/epidemiologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/virologia , Animais , República Democrática do Congo/epidemiologia , Genótipo , Vírus da Doença de Newcastle/isolamento & purificação , Filogenia , Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , RNA Viral/genética , Proteínas Virais/genética , Sequenciamento Completo do Genoma
2.
Viruses ; 12(12)2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302389

RESUMO

Control measures in the case of high pathogenicity avian influenza (HPAI) outbreaks in poultry include culling, surveillance, and biosecurity; wild birds in captivity may also be culled, although some rare bird species should be rescued for conservation. In this study, two anti-influenza drugs, baloxavir marboxil (BXM) and peramivir (PR), used in humans, were examined in treating HPAI in birds, using chickens as a model. Chickens were infected with H5N6 HPAI virus and were treated immediately or 24 h from challenge with 20 mg/kg BXM or PR twice a day for five days. As per our findings, BXM significantly reduced virus replication in organs and provided full protection to chickens compared with that induced by PR. In the 24-h-delayed treatment, neither drug completely inhibited virus replication nor ensured the survival of infected chickens. A single administration of 2.5 mg/kg of BXM was determined as the minimum dose required to fully protect chickens from HPAI virus; the concentration of baloxavir acid, the active form of BXM, in chicken blood at this dose was sufficient for a 48 h antiviral effect post-administration. Thus, these data can be a starting point for the use of BXM and PR in treating captive wild birds infected with HPAI virus.


Assuntos
Ácidos Carbocíclicos/farmacologia , Antivirais/farmacologia , Galinhas/virologia , Dibenzotiepinas/farmacologia , Guanidinas/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Influenza Aviária/tratamento farmacológico , Influenza Aviária/virologia , Morfolinas/farmacologia , Piridonas/farmacologia , Triazinas/farmacologia , Ácidos Carbocíclicos/uso terapêutico , Animais , Antivirais/uso terapêutico , Dibenzotiepinas/uso terapêutico , Monitoramento de Medicamentos , Guanidinas/uso terapêutico , Influenza Aviária/mortalidade , Morfolinas/uso terapêutico , Especificidade de Órgãos , Piridonas/uso terapêutico , Tempo para o Tratamento , Resultado do Tratamento , Triazinas/uso terapêutico , Eliminação de Partículas Virais
3.
Viruses ; 12(12)2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33327524

RESUMO

Global dispersion of high pathogenicity avian influenza (HPAI), especially that caused by H5 clade 2.3.4.4, has threatened poultry industries and, potentially, human health. An HPAI virus, A/northern pintail/Hokkaido/M13/2020 (H5N8) (NP/Hok/20) belonging to clade 2.3.4.4b, was isolated from a fecal sample collected at a lake in Hokkaido, Japan where migratory birds rested, October 2020. In the phylogenetic trees of all eight gene segments, NP/Hok/20 fell into in the cluster of European isolates in 2020, but was distinct from the isolates in eastern Asia and Europe during the winter season of 2017-2018. The antigenic cartography indicates that the antigenicity of NP/Hok/20 was almost the same as that of previous isolates of H5 clade 2.3.4.4b, whereas the antigenic distances from NP/Hok/20 to the representative strains in clade 2.3.4.4e and to a strain in 2.3.4 were apparently distant. These data imply that HPAI virus clade 2.3.4.4b should have been delivered by bird migration despite the intercontinental distance, although it was not defined whether NP/Hok/20 was transported from Europe via Siberia where migratory birds nest in the summer season. Given the probability of perpetuation of transmission in the northern territory, periodic updates of intensive surveys on avian influenza at the global level are essential to prepare for future outbreaks of the HPAI virus.


Assuntos
Genótipo , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A Subtipo H5N8/patogenicidade , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Animais , Animais Selvagens/virologia , Patos , Geografia Médica , História do Século XXI , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A , Influenza Aviária/história , Japão/epidemiologia , Filogenia , Virulência
4.
Virus Genes ; 56(5): 651-656, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32696325

RESUMO

Although rabies is enzootic in the Democratic Republic of the Congo, there is very little molecular epidemiological information about the viruses circulating in animals. In this study, a fragment of the rabies virus (RABV) nucleoprotein gene was amplified and sequenced from 21 animal brain samples collected in two western provinces of the country between 2008 and 2017. The samples tested were from cat (n = 1), dog (n = 17), goat (n = 2), and sheep (n = 1). Phylogenetic analysis revealed that the sequences generated were highly similar to each other and belonged to lineage Africa 1b clustering with a single sample identified in a canine in the Republic of Congo in 2014. This is the first molecular epidemiological study of RABV in the DRC and the data generated will assist authorities in the development of effective control strategies for rabies in the country.


Assuntos
Vírus da Raiva , Raiva , Animais , Gatos , República Democrática do Congo/epidemiologia , Cães , Cabras , Proteínas do Nucleocapsídeo/genética , Filogenia , RNA Viral/genética , Raiva/epidemiologia , Raiva/veterinária , Raiva/virologia , Vírus da Raiva/classificação , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Ovinos
5.
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
6.
Nat Commun ; 10(1): 5310, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31757953

RESUMO

The role of Africa in the dynamics of the global spread of a zoonotic and economically-important virus, such as the highly pathogenic avian influenza (HPAI) H5Nx of the Gs/GD lineage, remains unexplored. Here we characterise the spatiotemporal patterns of virus diffusion during three HPAI H5Nx intercontinental epidemic waves and demonstrate that Africa mainly acted as an ecological sink of the HPAI H5Nx viruses. A joint analysis of host dynamics and continuous spatial diffusion indicates that poultry trade as well as wild bird migrations have contributed to the virus spreading into Africa, with West Africa acting as a crucial hotspot for virus introduction and dissemination into the continent. We demonstrate varying paths of avian influenza incursions into Africa as well as virus spread within Africa over time, which reveal that virus expansion is a complex phenomenon, shaped by an intricate interplay between avian host ecology, virus characteristics and environmental variables.


Assuntos
Influenza Aviária/transmissão , Influenza Humana/transmissão , Doenças das Aves Domésticas/transmissão , África , África Ocidental , Animais , Humanos , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A/genética , Influenza Aviária/economia , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Influenza Humana/economia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/economia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia
7.
J Virol Methods ; 265: 121-125, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30633948

RESUMO

Rapid and accurate diagnosis of influenza virus infection is essential for quick responses for both human and animal health. The Alere™ i Influenza A&B is a novel isothermal nucleic acid amplification kit that can detect and differentiate between influenza A and B viruses in human specimens in approximately 15 min. In the present study, the performance of the Alere™ i Influenza A&B kit was evaluated for its ability to detect avian influenza virus in chickens. The kit was able to detect representative avian influenza virus strains (hemagglutinin subtypes H1-H16, including the recently isolated H5 and H7 highly pathogenic avian influenza viruses), and the detection limit of the kit for these viruses varied between 10-1.4-102.1 50% egg-infective dose per test, which is higher than the analytical sensitivity of the antigen detection immunochromatography kit ESPLINE® A INFLUENZA. In experimentally infected chickens inoculated with a highly pathogenic avian influenza virus strain A/chicken/Hokkaido/002/2016 (H5N6), viral RNA was detected in the tracheal and cloacal swabs. These results indicate that this kit has the potential to be used as a rapid screening test of influenza A virus infection in chickens.


Assuntos
Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Aviária/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Doenças das Aves Domésticas/diagnóstico , Animais , Galinhas , Cloaca/virologia , Vírus da Influenza A/genética , Vírus da Influenza B/genética , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Sensibilidade e Especificidade , Traqueia/virologia
8.
Emerg Infect Dis ; 24(7): 1371-1374, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29912707

RESUMO

In 2017, highly pathogenic avian influenza A(H5N8) virus was detected in poultry in the Democratic Republic of the Congo. Whole-genome phylogeny showed the virus clustered with H5N8 clade 2.3.4.4B strains from birds in central and southern Asia. Emergence of this virus in central Africa represents a threat for animal health and food security.


Assuntos
Vírus da Influenza A Subtipo H5N8 , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Animais , Galinhas , República Democrática do Congo/epidemiologia , Patos , Geografia , História do Século XXI , Humanos , Vírus da Influenza A Subtipo H5N8/classificação , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A Subtipo H5N8/patogenicidade , Influenza Humana/epidemiologia , Influenza Humana/história , Influenza Humana/virologia , Uganda/epidemiologia
9.
PLoS One ; 11(4): e0150403, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27054328

RESUMO

INTRODUCTION: Rabies is one of the major public health problems mostly affecting developing countries in Africa and Asia where 99.9% of all rabies related human deaths are recorded each year. In Democratic Republic of Congo, repeated outbreaks have been reported. Despite this, there is little reliable epidemiological data about rabies in the country for the development of effective control strategies. MATERIALS AND METHODS: A retrospective study was carried out in Kinshasa Province during a period of five years (2009-2013) to describe the proportion of rabid animals and the species involved in rabies transmission and maintenance. The survey also aimed at describing the spatial-temporal distribution of rabies. To gather information, the daily registers of institutions involved in rabies diagnosis were reviewed and each rabies case was traced back to area of occurrence for collection of geographic coordinates. RESULTS AND DISCUSSION: A total of 5,053 attacks were registered involving six animal species including dog, cat, monkey, rabbit, rat, and pig. Based on clinical observations, rabies was reported in dogs and cats while data obtained from the laboratory confirmed rabies cases included dogs, cats and a goat. The annual distribution showed a significant decrease of rabies cases from 2009 up to 2011 and a later increase up to 2013. There was no difference in rabies occurrence between seasons (p = 0.721). Rabies cases were three times higher in peri-urban zone than in urban zone OR = 3.4 (95% CI: 2.3-5.1). The positive proportion of rabies was 2.6% (95% CI: 2.1-3) based on clinical evidence and 65.9% (95% CI: 50-79.5) for laboratory confirmed cases. CONCLUSION AND SUGGESTION: This study confirms the endemicity of rabies in Kinshasa where occurrence of rabies cases was related to human population density and lifestyle. In order to control rabies, there is need to set up a surveillance program and implement efficient mass vaccination campaigns of susceptible animals.


Assuntos
Surtos de Doenças , Raiva/epidemiologia , Raiva/transmissão , Animais , Gatos , República Democrática do Congo/epidemiologia , Cães , Haplorrinos , Humanos , Coelhos , Ratos , Estudos Retrospectivos , Suínos
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