Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 90
Filtrar
1.
Viruses ; 13(8)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34452311

RESUMO

Since 2006, multiple outbreaks of avian influenza (AI) have been reported in Nigeria involving different subtypes. Surveillance and molecular epidemiology have revealed the vital role of live bird markets (LBMs) in the dissemination of AI virus to commercial poultry farms. To better understand the ecology and epidemiology of AI in Nigeria, we performed whole-genome sequencing of nineteen H9N2 viruses recovered, from apparently healthy poultry species, during active surveillance conducted in nine LBMs across Nigeria in 2019. Analyses of the HA gene segment of these viruses showed that the H9N2 strains belong to the G1 lineage, which has zoonotic potential, and are clustered with contemporary H9N2 identified in Africa between 2016 and 2020. We observed two distinct clusters of H9N2 viruses in Nigeria, suggesting different introductions into the country. In view of the zoonotic potential of H9N2 and the co-circulation of multiple subtypes of AI virus in Nigeria, continuous monitoring of the LBMs across the country and molecular characterization of AIVs identified is advocated to mitigate economic losses and public health threats.

2.
Transbound Emerg Dis ; 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33480188

RESUMO

Among recurrent sanitary emergencies able to spread rapidly worldwide, avian influenza is one of the main constraints for animal health and food security. In West Africa, Nigeria has been experiencing repeated outbreaks of different strains of avian influenza virus (AIV) since 2006 and is also recognized as a hot spot in the region for the introduction of emerging strains by migratory wild birds. Here, we generated complete genomes of 20 highly pathogenic avian influenza (HPAI) H5N8 viruses collected during active surveillance in Nigerian live bird markets (LBM) and from outbreaks reported in the country between 2016 and 2019. Phylogenetic analysis reveals that the Nigerian viruses cluster into four separate genetic groups within HPAI H5 clade 2.3.4.4b. The first group includes 2016-2017 Nigerian viruses with high genetic similarity to H5N8 viruses detected in Central African countries, while the second includes Nigerian viruses collected both in LBM and poultry farms (2018-2019), as well as in Cameroon, Egypt and Siberia. A natural reassortant strain identified in 2019 represents the third group: H5N8 viruses with the same gene constellation were identified in 2018 in South Africa. Finally, the fourth introduction represents the first detection in the African continent of the H5N6 subtype, which is related to European viruses. Bayesian phylogeographic analyses confirmed that the four introductions originated from different sources and provide evidence of the virus spread within Nigeria, as well as diffusion beyond its borders. The multiple epidemiological links between Nigeria, Central and Southern African countries highlight the need for harmonized and coordinated surveillance system to control AIV impact. Improved surveillance at the Wetlands, LBMs and early warning of outbreaks are crucial for prevention and control of AIV, which can be potentially zoonotic and be a threat to human health.

3.
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
4.
Transbound Emerg Dis ; 68(1): 152-167, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32613724

RESUMO

Comprehensive understanding of the patterns and drivers of avian influenza outbreaks is pivotal to inform surveillance systems and heighten nations' ability to quickly detect and respond to the emergence of novel viruses. Starting in early 2017, the Italian poultry sector has been involved in the massive H5N8 highly pathogenic avian influenza epidemic that spread in the majority of the European countries in 2016/2017. Eighty-three outbreaks were recorded in north-eastern Italy, where a densely populated poultry area stretches along the Lombardy, Emilia-Romagna and Veneto regions. The confirmed cases, affecting both the rural and industrial sectors, depicted two distinct epidemic waves. We adopted a combination of multivariate statistics techniques and multi-model regression selection and inference, to investigate how environmental factors relate to the pattern of outbreaks diversity with respect to their spatiotemporal and genetic diversity. Results showed that a combination of eco-climatic and host density predictors were associated with the outbreaks pattern, and variation along gradients was noticeable among genetically and geographically distinct groups of avian influenza cases. These regional contrasts may be indicative of a different mechanism driving the introduction and spreading routes of the influenza virus in the domestic poultry population. This methodological approach may be extended to different spatiotemporal scale to foster site-specific, ecologically informed risk mitigating strategies.


Assuntos
Surtos de Doenças/veterinária , Vírus da Influenza A Subtipo H5N8/fisiologia , Influenza Aviária/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Animais , Galinhas , Patos , Gansos , Variação Genética , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/virologia , Itália/epidemiologia , Doenças das Aves Domésticas/virologia , Análise Espaço-Temporal , Perus
5.
Transbound Emerg Dis ; 68(1): 37-50, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31788978

RESUMO

Effective control of avian diseases in domestic populations requires understanding of the transmission dynamics facilitating viral emergence and spread. In 2016-17, Italy experienced a significant avian influenza epidemic caused by a highly pathogenic A(H5N8) virus, which affected domestic premises housing around 2.7 million birds, primarily in the north-eastern regions with the highest density of poultry farms (Lombardy, Emilia-Romagna and Veneto). We perform integrated analyses of genetic, spatiotemporal and host data within a Bayesian phylogenetic framework. Using continuous and discrete phylogeography, we estimate the locations of movements responsible for the spread and persistence of the epidemic. The information derived from these analyses on rates of transmission between regions through time can be used to assess the success of control measures. Using an approach based on phylogenetic-temporal distances between domestic cases, we infer the presence of cryptic wild bird-mediated transmission, information that can be used to complement existing epidemiological methods for distinguishing transmission within the domestic population from incursions across the wildlife-domestic interface, a common challenge in veterinary epidemiology. Spatiotemporal reconstruction of the epidemic reveals a highly skewed distribution of virus movements with a high proportion of shorter distance local movements interspersed with occasional long-distance dispersal events associated with wild birds. We also show how such inference be used to identify possible instances of human-mediated movements where distances between phylogenetically linked domestic cases are unusually high.


Assuntos
Galinhas , Patos , Epidemias/veterinária , Vírus da Influenza A Subtipo H5N8/fisiologia , Influenza Aviária/transmissão , Doenças das Aves Domésticas/transmissão , Perus , Animais , Teorema de Bayes , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Itália/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Análise Espaço-Temporal
6.
Vet Microbiol ; 248: 108820, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32891950

RESUMO

In December 2018, suspected outbreaks of equine influenza (EI) were observed in donkeys in Sokoto State, in the extreme northwest of Nigeria bordering the Republic of the Niger. Equine influenza virus (EIV) subtype H3N8 was the etiologic agent identified in the outbreaks using real-time RT-qPCR and sequencing of both the partial haemagglutinin (HA) gene and the complete genome. Since then the H3N8 virus spread to 7 of the 19 northern states of Nigeria, where it affected both donkeys and horses. Phylogenetic analysis of the partial and complete HA gene revealed the closest nucleotide similarity (99.7%) with EIVs belonging to the Florida clade 1 (Fc-1) of the American lineage isolated in 2018 from Argentina and Chile. In total, 80 amino acid substitutions were observed in the viral proteins when compared to the OIE-recommended Fc-1 vaccine strains. The HA and neuraminidase proteins respectively had 13 and 16 amino acid substitutions. This study represents the first reported outbreak of EI caused by an Fc-1 virus in Nigeria and in the West Africa sub-region. Based on this report, extensive disease surveillance in equids is required to establish the circulating lineages and design an effective control strategy to protect the considerable population of horses and donkeys in the country.

7.
Front Microbiol ; 11: 1136, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523585

RESUMO

Bovine is considered the main reservoir of influenza D virus (IDV), however, low levels of seropositivity in other farmed species suggest a wide range of potential hosts. Nevertheless, it is not clear whether this scenario is the result of rare spillover events upon contact with bovines, or a lack of adaptation of IDV to these hosts. Among these species, sheep represents a crucial component of the rural economy in many developing countries, but little is known about its role in the ecology of the disease. To evaluate the susceptibility of sheep to IDV viruses of different origin, we used ovine respiratory tissues as an ex vivo model and investigated the infective phenotype of two IDV strains isolated from either bovine (IDV-BOV) or swine (IDV-SW). For translatability purposes, we included a parainfluenza type 3 virus, as positive control, given its known respiratory tropism in sheep. We performed a timed evaluation of the viral infectivity, cell tropism and the associated histopathology, by means of tissue culture infectious dose assays on supernatants and histological/immunohistochemical analyses on explanted tissues, respectively. To further investigate differences in the phenotype of these two strains and to identify the potential targets of replication in the most commonly land-based farmed mammalian species, we carried out virus binding assays on histological sections of the respiratory tract of bovine, caprine, ovine, horse and swine. Our results demonstrated that IDV successfully replicates in nasal, tracheal and lung ovine tissues, suggesting a moderate susceptibility of this species to IDV infection. Interestingly, despite the high genetic identity of these strains, IDV- BOV consistently replicated to higher titers than IDV-SW in all respiratory tracts, suggesting IDV viruses might display considerable levels of variability in their phenotype when crossing the species barrier. Virus binding assays confirmed a superior affinity of the IDV viruses for the bovine upper respiratory tract, and a preference for the pharyngeal epithelium of small ruminants, indicating possible targets to improve the sensitivity of virological sampling for diagnostic and post-mortem purposes. Further pathogenesis and cross-species transmission studies will be necessary to elucidate the ecology of IDV and eventually allow the design of cost-effective surveillance strategies.

8.
Sci Rep ; 10(1): 8441, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439885

RESUMO

Avian influenza viruses (AIV) are negative sense RNA viruses posing a major threat to the poultry industry worldwide, with the potential to spread to mammals, including humans; hence, an accurate and rapid AIV diagnosis is essential. To date AIV detection relies on molecular methods, mainly RT-qPCR directed against AIV M gene segment. The evolution of AIV represents a relevant issue in diagnostic RT-qPCR due to possible mispriming and/or probe-binding failures resulting in false negative results. Consequently, RT-qPCR for AIV detection should be periodically re-assessed both in silico and in vitro. To this end, a specific workflow was developed to evaluate in silico the complementarity of primers and probes of four published RT-qPCR protocols to their target regions. The four assays and one commercially available kit for AIV detection were evaluated both for their analytical sensitivity using eight different viral dilution panels and for their diagnostic performances against clinical specimens of known infectious status. Differences were observed among the tests under evaluation, both in terms of analytical sensitivity and of diagnostic performances. This finding confirms the importance of continuously monitoring the primers and probes complementarity to their binding regions.


Assuntos
Simulação por Computador , Variação Genética , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/diagnóstico , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Proteínas Virais/genética , Animais , Aves , Técnicas In Vitro , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/genética , Influenza Aviária/virologia , RNA Viral/genética , Curva ROC
9.
Transbound Emerg Dis ; 67(6): 2775-2788, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32438523

RESUMO

Avian coronaviruses, including infectious bronchitis virus (IBV) and turkey coronavirus (TCoV), are economically important viruses affecting poultry worldwide. IBV is responsible for causing severe losses to the commercial poultry sector globally. The objectives of this study were to identify the viruses that were causing outbreaks of severe respiratory disease in chickens in Trinidad and Tobago (T&T) and to characterize the strains. Swab samples were collected from birds showing severe respiratory signs in five farms on the island of Trinidad. Samples were tested for the presence of IBV, as well as avian influenza virus (AIV), Newcastle disease virus (NDV) and avian metapneumovirus (aMPV) by real-time reverse transcription polymerase chain reaction (qRT-PCR). All samples from the five farms tested negative for AIV, NDV and aMPV; however, samples from clinically affected birds in all five of the farms tested positive for IBV. Genetic data revealed the presence of TCoV in chickens on two of the farms. Interestingly, these two farms had never reared turkeys. Phylogenetic analysis showed that IBV S1 sequences formed two distinct clusters. Two sequences grouped with vaccine strains within the GI-1 lineage, whereas three sequences grouped together, but separately from other defined lineages, forming a likely new lineage of IBV. Pairwise comparison revealed that the three unique variant strains within the distinct lineage of IBV were significantly different in their S1 nucleotide coding regions from viruses in the closest lineage (16% difference) and locally used vaccine strains (>20% difference). Results also suggested that one of the samples was a recombinant virus, generated from a recombination event between a Trinidad virus of the GI-1 lineage and a Trinidad virus of the newly defined lineage. Many amino acid differences were also observed between the S1 coding regions of the circulating field and vaccine strains, indicating that the IBV vaccines may not be protective. Vaccine-challenge studies are however needed to prove this.


Assuntos
Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/isolamento & purificação , Doenças das Aves Domésticas/virologia , Infecções Respiratórias/veterinária , Vacinas Virais/imunologia , Animais , Galinhas , Infecções por Coronavirus/virologia , Patos , Gansos , Vírus da Bronquite Infecciosa/classificação , Filogenia , Codorniz , RNA Viral , Infecções Respiratórias/virologia , Análise de Sequência de RNA/veterinária , Trinidad e Tobago , Perus , Vacinação/veterinária
10.
Infect Genet Evol ; 84: 104359, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32407794

RESUMO

Canine distemper virus (CDV) represents an important threat for both wild and domestic carnivores. Since 2006, the North-Eastern regions in Italy have been experiencing severe and widespread recurring outbreaks of CDV affecting the wild carnivore population. In this study we performed an extensive phylogeographic analysis of CDV strains belonging to the Wildlife-Europe genetic group identified between 2006 and 2018 in Veneto, Trentino Alto Adige and Friuli Venezia Giulia regions. Our analysis revealed that viruses from the first (2006-2009) and the second (2011-2018) epidemic wave cluster separately, suggesting the introduction of two distinct genetic variants. These two events were characterized by different diffusion rates and spatial distribution, thus suggesting the existence of a connection between infection spread and host population dynamics. We also report the first spillover event of this strain to a non-vaccinated dog in a rural area of Friuli Venezia Giulia. The increasing prevalence of the infection in wildlife population, the broad host range of CDV circulating in the Alpine wildlife and the first reported transmission of a wild-adapted strain to a domestic dog in this region raise concerns over the vulnerability of wildlife species and the exposure of our pets to new threatening strains. Understanding the dynamic of CDV epidemics will also improve preparedness for re-emerging diseases affecting carnivore species.

11.
Emerg Microbes Infect ; 9(1): 851-854, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32403984

RESUMO

A second case of a novel rabies variant described once in a capuchin monkey from Mato Grosso, Brazil, was discovered in a rabid wild kinkajou from the same region, indicating a public health risk following exposure to either of the two animals.


Assuntos
Cebus/virologia , Procyonidae/virologia , Vírus da Raiva/isolamento & purificação , Raiva/transmissão , Animais , Brasil/epidemiologia , Genes Virais , Filogenia , Saúde Pública , Vírus da Raiva/genética
12.
Artigo em Inglês | MEDLINE | ID: mdl-32322405

RESUMO

Norovirus (NoV) has emerged as one of the major causative agents of non-bacterial, food- and water-borne gastroenteritis in humans, with the main genogroup involved in human outbreaks (GII), which has been detected worldwide in different animal species including swine. A four-month investigation at the slaughterhouse aiming to examine the presence of NoV in the swine in North-Eastern Italy, enabled the detection of two divergent Noroviruses (NoVs) (GII.P11) in two swine farms. This represents the first study in the swine population of North-Eastern Italy, which has paved the way for future integrated virological and epidemiological investigations on swine NoVs.

13.
Infect Genet Evol ; 83: 104342, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32348876

RESUMO

Since 2005, H5Nx highly pathogenic avian influenza (HPAI) viruses of the Goose/Guangdong (Gs/GD) lineage have spread worldwide, affecting poultry and wild birds in Asia, Europe, Africa and North America. So far, the role of Western Asia and the Middle East in the diffusion dynamics of this virus has been poorly explored. In order to investigate the genetic diversity and the role of Iran in the transmission dynamics of the Gs/GD lineage, we sequenced the complete genome of twenty-eight H5Nx viruses which were circulating in the country between 2016 and 2018. We reported the first characterization of the HPAI H5N6 subtype of clade 2.3.4.4B in Iran and gave evidence of the high propensity of the Gs/GD H5 AIVs to reassort, describing six novel H5N8 genotypes of clade 2.3.4.4B, some of them likely generated in this area, and one H5N1 reassortant virus of clade 2.3.2.1c. Our spatial analyses demonstrated that the viruses resulted from different viral introductions from Asia and Europe and provided evidence of virus spread from Iran to the Middle East. Therefore, Iran may represent a hot-spot for virus introduction, dissemination and for the generation of new genetic variability. Increasing surveillance efforts in this high-risk area is of utmost importance for the early detection of novel emerging strains with zoonotic potential.

14.
Bioinformatics ; 36(7): 2098-2104, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31790143

RESUMO

MOTIVATION: The potentially low precision associated with the geographic origin of sampled sequences represents an important limitation for spatially explicit (i.e. continuous) phylogeographic inference of fast-evolving pathogens such as RNA viruses. A substantial proportion of publicly available sequences is geo-referenced at broad spatial scale such as the administrative unit of origin, rather than more precise locations (e.g. geographic coordinates). Most frequently, such sequences are either discarded prior to continuous phylogeographic inference or arbitrarily assigned to the geographic coordinates of the centroid of their administrative area of origin for lack of a better alternative. RESULTS: We here implement and describe a new approach that allows to incorporate heterogeneous prior sampling probabilities over a geographic area. External data, such as outbreak locations, are used to specify these prior sampling probabilities over a collection of sub-polygons. We apply this new method to the analysis of highly pathogenic avian influenza H5N1 clade data in the Mekong region. Our method allows to properly include, in continuous phylogeographic analyses, H5N1 sequences that are only associated with large administrative areas of origin and assign them with more accurate locations. Finally, we use continuous phylogeographic reconstructions to analyse the dispersal dynamics of different H5N1 clades and investigate the impact of environmental factors on lineage dispersal velocities. AVAILABILITY AND IMPLEMENTATION: Our new method allowing heterogeneous sampling priors for continuous phylogeographic inference is implemented in the open-source multi-platform software package BEAST 1.10. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Animais , Surtos de Doenças , Filogenia , Filogeografia , Probabilidade
15.
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
16.
Viruses ; 11(12)2019 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-31801277

RESUMO

Influenza D virus (IDV) has been increasingly reported all over the world. Cattle are considered the major viral reservoir. Based on the hemagglutinin-esterase (HEF) gene, three main genetic and antigenic clusters have been identified: D/OK distributed worldwide, D/660 detected only in the USA and D/Japan in Japan. Up to 2017, all the Italian IDV isolates belonged to the D/OK genetic cluster. From January 2018 to May 2019, we performed virological surveillance for IDV from respiratory outbreaks in 725 bovine farms in Northern Italy by RT-PCR. Seventy-four farms were positive for IDV. A full or partial genome sequence was obtained from 29 samples. Unexpectedly, a phylogenetic analysis of the HEF gene showed the presence of 12 strains belonging to the D/660 cluster, previously unreported in Europe. The earliest D/660 strain was collected in March 2018 from cattle imported from France. Moreover, we detected one viral strain with a reassortant genetic pattern (PB2, PB1, P42, HEF and NP segments in the D/660 cluster, whilst P3 and NS segments in the D/OK cluster). These results confirm the circulation of IDV in the Italian cattle population and highlight the need to monitor the development of the spreading of this influenza virus in order to get more information about the epidemiology and the ecology of IDV viruses.


Assuntos
Doenças dos Bovinos/epidemiologia , Surtos de Doenças/veterinária , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados , Thogotovirus/classificação , Animais , Bovinos , Doenças dos Bovinos/virologia , Geografia , Itália/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Prevalência , Thogotovirus/genética , Thogotovirus/isolamento & purificação
17.
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
18.
Microbiol Resour Announc ; 8(41)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601657

RESUMO

Rabbit endogenous lentivirus type K (RELIK) was discovered in the genome of the European rabbit (Oryctolagus cuniculus). In our study, we present three complete genome sequences of RELIK viruses generated using a target amplification approach performed on the RNA of commercial rabbits from Italy.

19.
Vet Ital ; 55(3): 221-229, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31599546

RESUMO

Porcine astroviruses (PoAstV) are found in the gastrointestinal tract of healthy and diseased pigs worldwide. However, their role in causing enteric disease in pigs and other animals has not been elucidated. In the present report, we describe for the first time in Italy, the identification and genetic characterization, through whole genome sequencing, of a PoAstV2 in pigs in Northeast Italy in 2015. This instance is the first detection of PoAstV2 in pigs in Italy. The phylogenetic analysis of the complete ORF2 segment highlights the high similarity of this virus to those circulating that same year in Japan. There are very few full astrovirus genomes available, and the present data represent an important contribution towards a better understanding of the characteristics and evolution of these viruses.


Assuntos
Infecções por Astroviridae/veterinária , Genoma Viral , Mamastrovirus/genética , Doenças dos Suínos/virologia , Animais , Infecções por Astroviridae/virologia , Fezes/virologia , Feminino , Itália , Mamastrovirus/classificação , Filogenia , Análise de Sequência de RNA/veterinária , Sus scrofa , Suínos , Sequenciamento Completo do Genoma/veterinária
20.
Avian Dis ; 63(1): 24-30, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251516

RESUMO

In Morocco in early 2016, a low pathogenic avian influenza virus serotype H9N2 caused large economic losses to the poultry industry, with specific clinical symptoms and high mortality rates on infected farms. Subsequent to the H9N2 outbreak, the causal agent was successfully isolated from chicken flocks with high morbidity and mortality rates, propagated on embryonated eggs, and fully sequenced. The phylogenetic analysis suggested that the Moroccan isolate could have derived from the Middle East isolate A/chicken/Dubai/D2506.A/2015. This study was designed to assess the pathogenicity of the Moroccan isolate H9N2 in experimentally infected broiler and specific-pathogen-free (SPF) chickens. At 22 days of age, one broiler and two SPF chicken groups were inoculated by dropping 0.2 ml of the H9N2 isolate (107.5 EID50/ml) in both nostrils and eyes. Clinically inoculated chickens with H9N2 displayed mild lesions, low mortality rates, and an absence of clinical signs. The H9N2 virus was more pathogenic in broiler chickens and produced more severe tissue lesions compared to SPF chickens. The viral shedding was detected up to 6 days postinoculation (pi) in oropharyngeal and cloacal swabs in infected birds with a maximum shedding in the oropharynges of the broiler group. All experimental chickens seroconverted and registered high hemagglutination inhibition titers as early as day 7 pi. The present study indicates that the H9N2 virus isolated from a natural outbreak was of low pathogenicity under experimental conditions. However, under field conditions infection with other pathogens might have aggravated the disease.


Assuntos
Galinhas , Genoma Viral , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Animais , Marrocos , Filogenia , Organismos Livres de Patógenos Específicos , Virulência
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...