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1.
Viruses ; 13(1)2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375071

RESUMO

Bats are often claimed to be a major source for future viral epidemics, as they are associated with several viruses with zoonotic potential. Here we describe the presence and biodiversity of bats associated with intensive pig farms devoted to the production of heavy pigs in northern Italy. Since chiropters or signs of their presence were not found within animal shelters in our study area, we suggest that fecal viruses with high environmental resistance have the highest likelihood for spillover through indirect transmission. In turn, we investigated the circulation of mammalian orthoreoviruses (MRVs), coronaviruses (CoVs) and astroviruses (AstVs) in pigs and bats sharing the same environment. Results of our preliminary study did not show any bat virus in pigs suggesting that spillover from these animals is rare. However, several AstVs, CoVs and MRVs circulated undetected in pigs. Among those, one MRV was a reassortant strain carrying viral genes likely acquired from bats. On the other hand, we found a swine AstV and a MRV strain carrying swine genes in bat guano, indicating that viral exchange at the bat-pig interface might occur more frequently from pigs to bats rather than the other way around. Considering the indoor farming system as the most common system in the European Union (EU), preventive measures should focus on biosecurity rather than displacement of bats, which are protected throughout the EU and provide critical ecosystem services for rural settings.


Assuntos
Quirópteros , Suínos , Animais , Biodiversidade , Quirópteros/virologia , Vírus de DNA/classificação , Vírus de DNA/genética , Ecossistema , Filogenia , Vírus de RNA/classificação , Vírus de RNA/genética , Vírus Reordenados/genética , Suínos/virologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia , Viroses/veterinária
2.
Arch Virol ; 165(12): 2945-2951, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33030572

RESUMO

Minute virus of canines (MVC) belongs to the family Parvoviridae, genus Bocaparvovirus, and has been mainly described during enteritis episodes in young dogs. This study reports the characterization of four divergent MVC strains detected between 2012 and 2018, three of which were from dogs illegally imported into Italy, most probably from Eastern Europe, that cluster together phylogenetically but share low genetic similarity with the fourth MVC from an autochthonous dog and other available MVC sequences. Our data indicate that the introduction of genetically distinct MVC strains occurred through the illegal movement of dogs from a geographic area where a distinct MVC lineage was most likely circulating. Enforced surveillance of MVC in the dog population of Eastern Europe and its neighboring countries may shed light on, and eventually trace back to, illegal animal movements.


Assuntos
Doenças do Cão/virologia , Cães/virologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/isolamento & purificação , Animais , DNA Viral/química , DNA Viral/genética , Europa Oriental , Itália , Infecções por Parvoviridae/virologia , Parvovirus Canino/genética , Filogenia , Viagem
3.
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.

4.
Viruses ; 12(5)2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32456089

RESUMO

Mammalian Orthoreoviruses (MRV) are segmented dsRNA viruses in the family Reoviridae. MRVs infect mammals and cause asymptomatic respiratory, gastro-enteric and, rarely, encephalic infections. MRVs are divided into at least three serotypes: MRV1, MRV2 and MRV3. In Europe, swine MRV (swMRV) was first isolated in Austria in 1998 and subsequently reported more than fifteen years later in Italy. In the present study, we characterized two novel reassortant swMRVs identified in one same Italian farm over two years. The two viruses shared the same genetic backbone but showed evidence of reassortment in the S1, S4, M2 segments and were therefore classified into two serotypes: MRV3 in 2016 and MRV2 in 2018. A genetic relation to pig, bat and human MRVs and other unknown sources was identified. A considerable genetic diversity was observed in the Italian MRV3 and MRV2 compared to other available swMRVs. The S1 protein presented unique amino acid signatures in both swMRVs, with unexpected frequencies for MRV2. The remaining genes formed distinct and novel genetic groups that revealed a geographically related evolution of swMRVs in Italy. This is the first report of the complete molecular characterization of novel reassortant swMRVs in Italy and Europe, which suggests a greater genetic diversity of swMRVs never identified before.


Assuntos
Variação Genética , Orthoreovirus de Mamíferos/genética , Infecções por Reoviridae/virologia , Doenças dos Suínos/virologia , Animais , Proteínas do Capsídeo/genética , Chlorocebus aethiops , Europa (Continente) , Genoma Viral , Humanos , Itália , Mutação , Orthoreovirus de Mamíferos/classificação , Orthoreovirus de Mamíferos/isolamento & purificação , Filogenia , Sorogrupo , Suínos , Células Vero
5.
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.

6.
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
7.
J Virol Methods ; 260: 21-25, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29981296

RESUMO

Prompt and accurate diagnosis is warranted for infectious diseases of domestic animals which may have a significant impact on animal production or clinical practice. In this study, the identification and genetic characterization of a bovine enterovirus (BEV) strain isolated from a calf with diarrhea, are described. Two different next generation sequencing platforms were employed. Shotgun metagenomic accomplished by MinION sequencing (Oxford Nanopore Technologies) allowed the identification of BEV RNA from a cell-culture isolate. BEV was then confirmed by a specific real time RT-PCR assay. To achieve the whole genome of this isolate, sequence reads obtained by MinION were coupled with those originating from NextSeq500 (Illumina). Genomic relatedness and phylogeny with extant BEV strains is also reported. Overall, this manuscript highlights the use of the portable MinION sequence technology as a tool for support diagnostics in veterinary practice.


Assuntos
Diarreia/diagnóstico , Infecções por Enterovirus/diagnóstico , Enterovirus Bovino/genética , Enterovirus Bovino/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Animais , Bovinos , Chlorocebus aethiops , Diarreia/veterinária , Infecções por Enterovirus/veterinária , Fezes/virologia , Filogenia , RNA Viral/isolamento & purificação , Análise de Sequência de RNA , Células Vero , Sequenciamento Completo do Genoma
8.
Vet Rec ; 182(2): 51, 2018 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-29109181

RESUMO

Small ruminant lentivirus infections in goats affect both production and animal welfare. This represents a threat to the qualitative and quantitative growth of goat farming, recently observed in mountainous regions such as the Autonomous Province of Bolzano - South Tyrol (Italy). To monitor and eradicate the caprine arthritis encephalitis virus in this goat population, a compulsory eradication campaign was launched, based on a strict census of small ruminants and yearly serological testing of all animals, followed by the consequent culling of seropositive individuals. The campaign succeeded in completely eliminating cases of clinical disease in goats, while drastically reducing the seroprevalence at the herd as well as individual animal level. The serological outcome of the introduced control measures was determined using commercially available ELISA kits, demonstrating their suitability for use in this type of campaign, aimed at reducing seroprevalence as well as clinical manifestations of these infections. However, this clear success is diminished by the failure to achieve a complete eradication of these viruses. The reasons leading to the observed tailing phenomenon and the occurrence of new infections in already sanitised flocks are discussed and implementation of further measures are proposed.


Assuntos
Erradicação de Doenças , Doenças das Cabras/prevenção & controle , Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Logro , Animais , Vírus da Artrite-Encefalite Caprina/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Cabras/epidemiologia , Cabras , Itália/epidemiologia , Infecções por Lentivirus/epidemiologia , Infecções por Lentivirus/prevenção & controle , Avaliação de Programas e Projetos de Saúde , Vigilância de Evento Sentinela/veterinária , Estudos Soroepidemiológicos , Testes Sorológicos/veterinária
9.
Vet Microbiol ; 195: 25-29, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27771067

RESUMO

In August 2012 repeated respiratory outbreaks caused by swine influenza A virus (swIAV) were registered for a whole year in a breeding farm in northeast Italy that supplied piglets for fattening. The virus, initially characterized in the farm, was a reassortant Eurasian avian-like H1N1 (H1avN1) genotype, containing a haemagglutinin segment derived from the pandemic H1N1 (A(H1N1)pdm09) lineage. To control infection, a vaccination program using vaccines against the A(H1N1)pdm09, human-like H1N2 (H1huN2), human-like H3N2 (H3N2), and H1avN1 viruses was implemented in sows in November 2013. Vaccine efficacy was assessed by sampling nasal swabs for two months in 35-75 day-old piglets born from vaccinated sows. Complete genome sequencing of eight swIAV-positive nasal swabs collected longitudinally from piglets after the implementation of the vaccination program was conducted to investigate the virus characteristics. Over the two-month period, two different genotypes involving multiple reassortment events were detected. The unexpected circulation of multiple reassortant genotypes in such a short time highlights the complexity of the genetic diversity of swIAV and the need for a better surveillance plan, based on the combination of clinical signs, epidemiological data and whole genome characterization.


Assuntos
Genótipo , Vírus da Influenza A Subtipo H1N2/genética , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , Surtos de Doenças/veterinária , Vírus da Influenza A Subtipo H1N2/classificação , Itália/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
10.
Virol J ; 13: 139, 2016 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-27519739

RESUMO

Mammalian Orthoreoviruses 3 (MRV3) have been described in diarrheic pigs from USA and Asia. We firstly detected MRV3 in Europe (Italy) in piglets showing severe diarrhea associated with Porcine Epidemic Diarrhea. The virus was phylogenetically related to European reoviruses of human and bat origin and to US and Chinese pig MRV3.


Assuntos
Diarreia/veterinária , Orthoreovirus Mamífero 3/isolamento & purificação , Infecções por Reoviridae/veterinária , Doenças dos Suínos/virologia , Animais , Diarreia/virologia , Europa (Continente) , Orthoreovirus Mamífero 3/classificação , Orthoreovirus Mamífero 3/genética , Filogenia , Infecções por Reoviridae/virologia , Sus scrofa , Suínos
11.
PLoS Curr ; 72015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25932349

RESUMO

Influenza A viruses in swine cause considerable economic losses and raise concerns about their zoonotic potential. The current paucity of thorough empirical assessments of influenza A virus infection levels in swine herds under different control interventions hinders our understanding of their effectiveness. Between 2012 and 2013, recurrent outbreaks of respiratory disease caused by a reassortant pandemic 2009 H1N1 (H1N1pdm) virus were registered in a swine breeding farm in North-East Italy, providing the opportunity to assess an outbreak response plan based on vaccination and enhanced farm management. All sows/gilts were vaccinated with a H1N1pdm-specific vaccine, biosecurity was enhanced, weaning cycles were lengthened, and cross-fostering of piglets was banned. All tested piglets had maternally-derived antibodies at 30 days of age and were detectable in 5.3% of ~90 day-old piglets. There was a significant reduction in H1N1pdm RT-PCR detections after the intervention. Although our study could not fully determine the extent to which the observed trends in seropositivity or RT-PCR positivity among piglets were due to the intervention or to the natural course of the disease in the herd, we provided suggestive evidence that the applied measures were useful in controlling the outbreak, even without an all-in/all-out system, while keeping farm productivity at full.

12.
Clin Vaccine Immunol ; 21(5): 603-12, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554694

RESUMO

Outbreaks of low-pathogenicity avian influenza (LPAI) viruses of the H7N3 subtype were first detected in Italy in October 2002, and the virus continued to circulate between 2002 and 2004 in a densely populated poultry area in the northeast portion of that country. This virus circulated in unvaccinated and vaccinated poultry farms, and the infection was controlled in August 2003 by culling, control of movements, improved biosecurity, and heterologous vaccination. In 2004, H7N3 reoccurred in vaccinated poultry farms in which infection had been successfully controlled by the vaccination program. To shed light on this occurrence and the temporal pattern and genetic basis of antigenic drift for avian influenza viruses (AIVs) in the absence and presence of heterologous vaccination, a collection of H7N3 viruses isolated in 2002 and 2004 were characterized genetically and antigenically. Molecular analysis showed that viruses isolated in the 2004 outbreaks after the implementation of vaccination had acquired specific amino acid signatures, most of which were located at reported antibody binding sites of the hemagglutinin (HA) protein. Antigenic characterization of these 2004 isolates showed that they were antigenically different from those isolated prior to the implementation of vaccination. This is the first report on antigenic and genetic evolution of H7 LPAI viruses following the application of heterologous vaccination in poultry. These findings may have an impact on control strategies to combat AI infections in poultry based on vaccination.


Assuntos
Surtos de Doenças , Evolução Molecular , Vírus da Influenza A Subtipo H7N3/classificação , Vírus da Influenza A Subtipo H7N3/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Aviária/prevenção & controle , Influenza Aviária/virologia , Substituição de Aminoácidos , Animais , Deriva Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H7N3/genética , Vírus da Influenza A Subtipo H7N3/isolamento & purificação , Influenza Aviária/epidemiologia , Itália/epidemiologia , Dados de Sequência Molecular , Proteínas Mutantes/genética , Proteínas Mutantes/imunologia , Aves Domésticas , RNA Viral/genética , Seleção Genética , Análise de Sequência de DNA
13.
Vet Microbiol ; 165(3-4): 443-7, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-23608476

RESUMO

Previous studies have reported the detection of H5N1 HPAI virus in feathers from ducks naturally and experimentally infected and suggested that feather calami (FC) could be used as diagnostic samples for the early detection of H5N1 HPAI infections. Ducks are readily infected with H5N1 HPAI viruses although the development of clinical signs and deaths were reported as age-related with younger birds being more susceptible. The correlation between age and virus localisation in FC of infected ducks has not been studied to date. In the present study juvenile (4-week-old) and adult (24-week-old) Pekin ducks (Anas platyrhynchos var. domestica) were infected experimentally with a clade 2.2 H5N1 HPAI virus (A/duck/Nigeria/1071-23/2007). Tracheal (Tr) and cloacal (Cl) swabs and FC were collected at 3, 5, 7 and 10 days post infection and tested by RRT-PCR and a double antibody sandwich-ELISA (DAS-ELISA) developed in house. Virus was detected in swabs and FC of challenged ducks with a higher rate of detection in juvenile ducks. In this age group virus was detected over a longer period of time in FC compared to swabs. Our study showed that FC samples collected from young ducks are a valid diagnostic specimen for H5N1 HPAI virus detection. The DAS-ELISA on FC proved to be a suitable alternative diagnostic test when molecular and/or virus isolation techniques are not available therefore it could be useful in the diagnosis of H5N1 HPAI infections in under-resourced countries.


Assuntos
Patos/virologia , Plumas/virologia , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Aviária/diagnóstico , Fatores Etários , Animais , Ensaio de Imunoadsorção Enzimática/normas , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/imunologia , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Aviária/imunologia , Influenza Aviária/virologia , Reação em Cadeia da Polimerase/normas , Reprodutibilidade dos Testes , Traqueia/virologia
14.
Vet Microbiol ; 165(1-2): 177-83, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23597652

RESUMO

Avian influenza viruses of the H9N2 subtype have circulated in the poultry population in Asia, Far and Middle East since the mid-1990 s. One of the most widespread lineages established in poultry is the G1 lineage. This lineage has undergone further evolution and reassortment since its first detection in 1997 and G1-like H9N2 viruses still circulate. In this study we have investigated the susceptibility of quail and turkeys to the H9N2 G1-lineage prototype strain (A/quail/Hong Kong/G1/97). Contact transmission experiments were carried out in both avian species. Animals were infected oro-nasally with increasing doses of the virus (10(3)-10(6) EID 50/0.1 ml) and sentinel birds were introduced 4 days post infection (pi) in each experimental group. Quail were more susceptible than turkeys, as they were readily infected with lower challenge doses. Interestingly, infection of turkeys was associated with worse clinical condition. Transmission was detected in both species. Quail infected with a dose less than or equal to 10(4) EID50 transmitted the virus to the sentinels without showing any signs of disease. These findings reinforce the hypothesis that quail may ensure the perpetuation of H9N2 viruses in poultry, acting as a silent reservoir.


Assuntos
Coturnix/virologia , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/transmissão , Influenza Aviária/virologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Perus/virologia , Animais , Genótipo , Vírus da Influenza A Subtipo H9N2/classificação , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Filogenia , Virulência , Eliminação de Partículas Virais
15.
Virology ; 435(2): 350-6, 2013 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-23123011

RESUMO

The extensive circulation of Highly Pathogenic (HP) H5N1 Avian Influenza in Egypt in poultry since 2006 resulted in the emergence of distinct clades with the recent identification of a further clade: 2.2.1.1. The aim of this study was to characterize for the first time the antigenic profile of an extensive collection of genetically diverse Egyptian H5N1 HP viruses isolated between 2007 and 2010 applying antigenic cartography and principal component analysis to serological data. We identified that Egyptian H5N1 viruses have undergone significant antigenic diversification between 2007 and 2010 and two distinct antigenic clusters co-circulated in 2010. Such clusters correlated with 2.2.1 and 2.2.1.1 clades, showing for the first time that the new emerging clade 2.2.1.1 is antigenically distinct. This study highlights that the antigenic diversity of H5N1 HP Egyptian viruses may represent a potential challenge for the development of an effective vaccination programme for animal and human health in Egypt.


Assuntos
Variação Antigênica , Virus da Influenza A Subtipo H5N1/classificação , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Animais , Antígenos Virais/genética , Antígenos Virais/imunologia , Galinhas/genética , Galinhas/imunologia , Galinhas/virologia , Egito , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Aviária/prevenção & controle , Dados de Sequência Molecular , Filogenia , Aves Domésticas/genética , Aves Domésticas/imunologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA , Vacinação
16.
Virology ; 433(2): 522-7, 2012 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-23017502

RESUMO

The aims of this study were to assess the infectivity of highly pathogenic (HP) and low pathogenicity (LP) H7 AI viruses at different temperatures and pH values and to investigate the persistance of HP H7 virus in chicken, turkey and duck meat. The H7 viruses tested remained infectious at +4°C and +20°C for 200 and >50 days, respectively. At pH 5, H7 viruses retained their infectivity for a shorter period of time compared to pH 7. The infectivity of HP H7 was detected >2 months in meat maintained at +4°C and was higher in chicken meat compared to turkey and duck meat. Results of this study show that higher temperatures and lower pH values both reduce virus infectivity and demonstrate that HP H7 virus can remain infectious in meat for extended periods of time.


Assuntos
Vírus da Influenza A/patogenicidade , Carne/virologia , Aves Domésticas/virologia , Animais , Galinhas/virologia , Patos/virologia , Microbiologia de Alimentos , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Vírus da Influenza A/classificação , Temperatura , Fatores de Tempo , Perus/virologia , Virulência
17.
Vet Microbiol ; 154(3-4): 209-21, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21925809

RESUMO

Since 2006, the members of the molecular epidemiological working group of the European "EPIZONE" network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation and impact of these viruses. This review presents a timely update on the epidemiological situation of these viruses based on sequence data generated during the lifetime of this project in addition to data produced by other groups during the same period. Based on this information and putting it all into a European context, recommendations for continued surveillance of these important viruses within Europe are presented.


Assuntos
Infecções por Avulavirus/genética , Avulavirus/genética , Vírus da Influenza A/genética , Influenza Aviária/genética , Animais , Infecções por Avulavirus/epidemiologia , Infecções por Avulavirus/veterinária , Aves , Europa (Continente)/epidemiologia , Humanos , Influenza Aviária/epidemiologia , Doença de Newcastle/epidemiologia , Doença de Newcastle/genética , Vigilância da População , Análise de Sequência de DNA
18.
Avian Pathol ; 39(5): 375-82, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20954014

RESUMO

Vaccination against avian influenza (AI) is now included amongst the prevention and control measures recommended by international animal health organizations to combat the disease in poultry. For optimal control of human influenza infections, the antigenic variability within subtypes requires the annual update of seed strains for inclusion in vaccines. The decisions taken are based on serological cross-reactivity of viral strains measured by haemagglutination inhibition (HI) tests. The reason for this is to ensure that the vaccine contains strains that are related antigenically to the current circulating field strain as field viruses evolve or are substituted by variants of distinct antigenicity. Such an annual approach is not viable economically for the poultry industry. In the current study, we have applied a similar HI-based approach to demonstrate, as proof of principle, that cross-reactive strains can be identified. Applying the same approach used by the World Health Organization to investigate antigenic differences among human influenza viruses, we assessed the serological cross-reactivity of a selection of natural H5 and H7 subtype viruses. Analysing HI data, we have identified strains that are cross-reactive and may have the potential to act as seed viruses for future vaccine development. This study should be considered a starting point for a more informed approach to the selection of seed strains for the development of avian influenza vaccines against field infections caused by viruses of H5 and H7 subtypes.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/genética , Vacinas contra Influenza/imunologia , Influenza Aviária/prevenção & controle , Influenza Aviária/virologia , Animais , Antígenos Virais/classificação , Antígenos Virais/genética , Galinhas , Filogenia , Testes Sorológicos
19.
Avian Pathol ; 38(6): 519-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19937542

RESUMO

The increased attention of the international community to the occurrence of repeated outbreaks of avian influenza infections worldwide has highlighted several knowledge gaps in the field. Among these, within the scope of the European Union-funded project Fluresist, we addressed the resistance of selected H7 subtype strains at 37 degrees C. In general terms, resistance was high, although some strains were more resistant than others, remaining viable after 15 days at 37 degrees C. These results should be considered when designing guidelines for outbreak management.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza , Temperatura Alta , Vírus da Influenza A/classificação , Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Adaptação Fisiológica , Animais , Itália/epidemiologia , Aves Domésticas , Fatores de Tempo , Virulência
20.
Avian Pathol ; 38(3): 193-200, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19468935

RESUMO

The extensive circulation of the H5N1 highly pathogenic avian influenza virus, and the human health threat that it poses, has raised concerns over the food safety implications of this virus infecting poultry. In addition, among the most important risk factors for the possible emergence of avian influenza in the European Union and the United States, the European and Food Safety Agency and the US Department of Agriculture's Animal and Plant Health Inspection Service, respectively, have identified legal and illegal importations of infected poultry commodities. The present paper reviews existing knowledge on the presence of viable avian influenza viruses in poultry commodities.


Assuntos
Ovos/virologia , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Produtos Avícolas/virologia , Animais , Sangue/virologia , Europa (Continente)/epidemiologia , Plumas/virologia , Aves Domésticas , Prevalência
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