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1.
J Appl Microbiol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627246

RESUMO

AIMS: The present study aimed to use a conventional and metagenomic approach to investigate the microbiological diversity of water bodies in a network of drainage channels and rivers located in the central area of the city of Belém, Northern Brazil, which is considered one of the largest cities in the Brazilian Amazon. METHODS AND RESULTS: In eight of the analyzed points, both bacterial and viral microbiological indicators of environmental contamination, the physical-chemical and metals were assessed. The bacterial resistance genes, drug resistance mechanisms, and viral viability in the environment were also assessed. A total of 473 families of bacteria and 83 families of viruses were identified. Based on the analysis of metals, the levels of three metals (Cd, Fe, and Mn) were found to be above the recommended acceptable level by local legislation. The levels of the following three physicochemical parameters were also higher than recommended: Biochemical Oxygen Demand, dissolved oxygen, and turbidity. Sixty-three bacterial resistance genes that conferred resistance to 13 different classes of antimicrobials were identified. Further, five mechanisms of antimicrobial resistance were identified and viral viability in the environment was confirmed. CONCLUSIONS: Intense human actions combined with a lack of public policies and poor environmental education of the population cause environmental degradation, especially in water bodies. Thus, urgent interventions are warranted to restore the quality of this precious and scarce asset worldwide.

2.
J Med Virol ; 95(6): e28873, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37349989

RESUMO

In this investigation, fecal specimens from children with diarrhea were collected from four community studies conducted between 1982 and 2019 in Belém, Brazilian Amazon. A total of 234 samples were tested by quantitative reverse transcription polymerase chain reaction (RT-qPCR) to detect infections by picornaviruses of the Enterovirus (EV), Parechovirus (HPeV), Cosavirus (HCoSV), Kobuvirus (Aichivirus - AiV) and Salivirus (SalV) genera. The positive samples were subjected to different amplification protocols of the VP1 region of the genome, such as nested PCR or snPCR, and were subsequently genotyped by sequencing VP1 and VP3 of the viral genome. Positivity was observed in 76.5% (179/234) of the samples tested using RT-qPCR for at least one virus, and co-infection was observed in 37.4% (67/179) of the cases. EV was detected in 50.8% (119/234), HPeV in 29.9% (70/234), HCoSV in 27.3% (64/234), and AiV/SalV in 2.1% (5/234) of the specimens tested by RT-qPCR. Using nested PCR and/or snPCR techniques, the positivity rates were 94.11% (112/119) for EV, 72.85% (51/70) for HPeV, and 20.31% (13/64) for HCoSV. It was not possible to amplify the samples that were positive for AiV/SalV. Sequencing revealed 67.2% (80/119) EV, 51.4% (36/70) HPeV, and 20.31% (13/64) HCoSV. Forty-five different types of EV were found among species A, B, and C; HCoSV identified five species, including a possible recombinant strain; all HPeV were identified as belonging to species A, in two samples a possible recombination involving three different strains was verified. This study demonstrated the high circulation and diversity of different types of picornaviruses in fecal samples, including those collected more than 30 years ago. This endorsed the evaluation of important points in the epidemiology of these viruses, such as the presence of co-infection and the possibility of knowing more about these agents, considering that some were recently described; therefore, their detection in older samples can provide more data about their ancestry.


Assuntos
Coinfecção , Infecções por Enterovirus , Enterovirus , Infecções por Picornaviridae , Picornaviridae , Vírus , Criança , Humanos , Idoso , Picornaviridae/genética , Coinfecção/epidemiologia , Brasil/epidemiologia , Infecções por Enterovirus/epidemiologia , Enterovirus/genética , Diarreia/epidemiologia
3.
Virol J ; 18(1): 148, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34266453

RESUMO

On the detection and identification of enteroviruses circulating in children with acute gastroenteritis in Brazil: reply to Luchs, A. Comments on Detection and identification of enteroviruses circulating in children with acute gastroenteritis in Pará State, Northern Brazil (2010-2011).


Assuntos
Infecções por Enterovirus , Enterovirus , Gastroenterite , Brasil , Criança , Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/epidemiologia , Gastroenterite/diagnóstico , Gastroenterite/epidemiologia , Humanos , Filogenia
4.
Virol J ; 17(1): 156, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066782

RESUMO

Although acute gastroenteritis (AGE) has been reported as a common infectious disease in children, there is scarce information about enterovirus (EV) circulating associated with AGE cases in Brazil. The purpose of the present study was to identify and characterize the enteroviruses associated with AGE in children in Belém, Brazil. A total of 175 stool samples were obtained from children hospitalized revealing the presence of EV in 26.3% (46/175) of infections. EV type was identified in 78.3% (36/46) and EV-B species (61.1%; 22/36) was the most prevalent EV-detected followed by EV-C (25%; 9/36) and EV-A (13.9%; 5/36). This study has provided important information about the enterovirus circulation in Pará state, Northern Brazil.


Assuntos
Infecções por Enterovirus/epidemiologia , Enterovirus/genética , Enterovirus/isolamento & purificação , Gastroenterite/epidemiologia , Gastroenterite/virologia , Doença Aguda/epidemiologia , Brasil/epidemiologia , Pré-Escolar , Enterovirus/classificação , Infecções por Enterovirus/virologia , Fezes/virologia , Genótipo , Humanos , Lactente , Filogenia
5.
J Med Virol ; 92(8): 1075-1084, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31840822

RESUMO

In the current investigation, fecal material was obtained during a community-based longitudinal study conducted from 1983 to 1986. This study consisted of 71 children aged newborn to 3 years. A total of 216 samples from three of these children were screened by real-time quantitative polymerase chain reaction (RT-qPCR) for the presence of enteroviruses, and positive samples were serotyped by VP1 and VP3 sequencing of the viral genome. Of these, 12 (5.6%) came from symptomatic cases, and the remaining asymptomatic cases were collected fortnightly during the 3 years of study. A positivity of 63.4% (137/216) was obtained by RT-qPCR, with 58.3% (7/12) in relation to the symptomatic group and 63.7% (130/204) in relation to the asymptomatic group. The 137 positive samples were inoculated into the RD, HEp2C, and L20B cell lines, and the cytopathic effect was observed in 37.2% (51/137) samples. It was also possible to identify 40.9% (56/137), between isolated (n = 46) and nonisolated (n = 10). Enterovirus serotype diversity (n = 25) was identified in this study, with the predominant species being B (80.3%), followed by C (16.1%) and A (3.6%). Cases of reinfection by different serotypes were also observed in the three children studied. Analyses involving different age groups of these minors confirmed that the most affected age was between 12 to 24 months, with a prevalence of 77.6% (52/67). The enterovirus (EV) circulated in the 3 years of research, showed peaks in some months, without defined seasonality. This study demonstrated a high circulation and serotype diversity of EV in fecal samples, collected over 30 years ago. This endorsed the evaluation of important points of the epidemiology of these viruses, such as the presence of coinfection and reinfection of the same individual by different circulating serotypes. Understanding the frequency and duration of EV infections is important in determining their association with persistent diarrhea.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/genética , Fezes/virologia , Gastroenterite/virologia , Brasil/epidemiologia , Pré-Escolar , Enterovirus/classificação , Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/epidemiologia , Gastroenterite/epidemiologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Filogenia , Sorogrupo , Sorotipagem
6.
Mem Inst Oswaldo Cruz ; 113(11): e170538, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30379197

RESUMO

This study showed that laboratory markers of recent infection by dengue, Zika or chikungunya arboviruses were detected in the biological samples of approximately one-third of patients with encephalitis, myelitis, encephalomyelitis or Guillain-Barré syndrome, in a surveillance programme in Piauí state, Brazil, between 2015-2016. Fever and myalgia had been associated with these cases. Since in non-tropical countries most infections or parainfectious diseases associated with the nervous system are attributed to herpesviruses, enteroviruses, and Campylobacter jejuni, the present findings indicate that in tropical countries, arboviruses may now play a more important role and reinforce the need for their surveillance and systematic investigation in the tropics.


Assuntos
Vírus Chikungunya , Vírus da Dengue , Doenças do Sistema Nervoso/virologia , Zika virus , Doença Aguda , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Encefalite/diagnóstico , Encefalite/virologia , Encefalomielite Aguda Disseminada/diagnóstico , Encefalomielite Aguda Disseminada/virologia , ELISPOT , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/virologia , Humanos , Mielite Transversa/diagnóstico , Mielite Transversa/virologia , Doenças do Sistema Nervoso/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Zika virus/genética , Zika virus/imunologia
9.
Mem. Inst. Oswaldo Cruz ; 113(11): e170538, 2018. tab
Artigo em Inglês | LILACS | ID: biblio-1040584

RESUMO

This study showed that laboratory markers of recent infection by dengue, Zika or chikungunya arboviruses were detected in the biological samples of approximately one-third of patients with encephalitis, myelitis, encephalomyelitis or Guillain-Barré syndrome, in a surveillance programme in Piauí state, Brazil, between 2015-2016. Fever and myalgia had been associated with these cases. Since in non-tropical countries most infections or parainfectious diseases associated with the nervous system are attributed to herpesviruses, enteroviruses, and Campylobacter jejuni, the present findings indicate that in tropical countries, arboviruses may now play a more important role and reinforce the need for their surveillance and systematic investigation in the tropics.


Assuntos
Humanos , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Zika virus/genética , Zika virus/imunologia , Doença Aguda , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/virologia , Encefalite/diagnóstico , Encefalite/virologia , Encefalomielite Aguda Disseminada/diagnóstico , Encefalomielite Aguda Disseminada/virologia , ELISPOT , Mielite Transversa/diagnóstico , Mielite Transversa/virologia , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/virologia
10.
Hum Vaccin Immunother ; 13(3): 717-723, 2017 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-27901633

RESUMO

The last case of paralytic poliomyelitis caused by wild poliovirus in Brazil occurred in 1989. The interruption of the indigenous poliovirus transmission was obtained through mass immunization campaigns to eligible children and an active epidemiological and laboratorial surveillance of all cases of acute flaccid paralysis (AFP) among children under 15 y of age. This paper describes and evaluates the performance of the AFP surveillance system in different geographic areas of Brazil between 2005 and 2014, using indicators recommended by WHO. AFP surveillance indicators as well as virological investigation of polio and non-polio enteroviruses in stool samples received in the laboratory were assessed from 2005-2014. During the period, 5463 cases of AFP were investigated. Of these, 55% were males and 45% were females. Those under 5 y of age represented 48% of all cases reported and investigated. AFP notification rate was within the acceptable values with mean value of 1.3 (North), 1.4 (Northeast), 1.1 (Southern), 1.0 (Southeast) and 1.4 (Midwest) cases of AFP per 100.000 population aged 15 y as well as the adequacy of fecal specimens received in the laboratory. Sabin- related polioviruses accounted for 1.7% of the isolates while, 6.7% were non-polio enterovirus with the values ranging from 5.0% to 8.9 %. No wild-type polio was found. The AFP epidemiological and laboratorial surveillance activities have been kept at appropriate levels in Brazil. These data are a very strong indication, which supports the status of country free of polio.


Assuntos
Enterovirus/classificação , Enterovirus/isolamento & purificação , Monitoramento Epidemiológico , Fezes/virologia , Paraplegia/epidemiologia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
11.
Infect Genet Evol ; 41: 142-145, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27071531

RESUMO

In May 2015 the first autochthonous Zika virus infection was reported in Brazil. Rapid and urgent measures are needed to contain the ongoing outbreak. Here we report the full-length ZIKV coding sequence from Bahia. Genetic analysis of outbreak sequences will be essential for characterizing the diversity of circulating strains, identifying hotspots of virus transmission and guiding public health control. Rapid and urgent measures are needed to contain the ongoing outbreak.


Assuntos
Genoma Viral/genética , Infecção por Zika virus/virologia , Zika virus/genética , Brasil , Feminino , Humanos , Pessoa de Meia-Idade , Filogenia
12.
Mem Inst Oswaldo Cruz ; 107(5): 698-701, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22850966

RESUMO

Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.


Assuntos
Primers do DNA/genética , Poliomielite/virologia , Vacina Antipólio Oral/genética , Poliovirus/genética , Genoma Viral , Humanos , Mutação , Fenótipo , Poliomielite/imunologia , Poliovirus/imunologia , Vacina Antipólio Oral/imunologia , Reação em Cadeia da Polimerase em Tempo Real
13.
Mem. Inst. Oswaldo Cruz ; 107(5): 698-701, Aug. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-643761

RESUMO

Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.


Assuntos
Humanos , Primers do DNA/genética , Poliomielite/virologia , Vacina Antipólio Oral/genética , Poliovirus/genética , Genoma Viral , Mutação , Fenótipo , Poliomielite/imunologia , Vacina Antipólio Oral/imunologia , Poliovirus/imunologia , Reação em Cadeia da Polimerase em Tempo Real
14.
Rio de Janeiro; s.n; 2012. xiv,106 p. graf, tab, ilus.
Tese em Português | LILACS | ID: lil-691486

RESUMO

Os enterovírus humanos ( Picornavirdae) são vírus de transmissão predominantemente entéric, podem ser encontrados em todas as regiões do mundo e são um dos agentes mais prevalentes entre os causadores de doenãs em humanos.Atualmente mais de 100 sorotipos de enterovírus humanos foram descritos e grande parte das infecções são assintomáticas.Surtos e casos esporádicos de enteroviroses são frequentemente notificados em diversas regiões do mundo causando conjutivite hemorrágica aguda,meningite asséptica,doença de mão pé e boca e poliomielite.A poliomielite é uma doença infecciosa de caráter agudo, que pode assumir desde formas assintomáticas até formas paralíticas, que ocorre seguida a uma infecção causada por um dos três sorotipos de poliovírus(PV). No Brasil, a poliomielite foi eliminada em 1989 graças à utilização da vacina oral atenuada desenvolvida por Sabin e licenciada no início dos anos 60.Os PV selvagens estão hoje restritos a apenas quatro países( Nigéria,Afeganistão,Paquistão e Índia). Entretanto vários surtos causados pela reintrodução dos poliovírus selvagens em países que já haviam eliminado o vírus tem sido relatados.Com o objetivo de se caracterizar geneticamente os polivírus selavagens que cirularam no Brasil, a análise de três regiões distintas do genoma viral(VP, protease 2C e polimerase 3D) foi realizada.Foram utilizados poliovírus isolados de casos de paralisia flácida aguda que ocorreram no Brasil, no período de 1981 a 1988. No estudo foi realizado também osequenciamento nucleotídico do genoma completo de uma amostra de PV! Que circulou na região Nordeste em 1988. Sessenta e um isolados foram analisados (31 PV1 E 30 PV3) inicialmente por RT-PCR, para a confirmação do sorotipo, e posteriormente por sequenciamento nucleotídico. A análise do gene que codifica a principal proteína do capsídeo viral,VP1, demonstrou que apenas um genótipo, para cada um dos dois sorotipos de PV estudados,estava em circulação no Brasil à época em que os PV selvagens que circularam no Brasil no período de estudo.As amostras brasileiras de PV1 apresentaram uma maior identidade com amostras virais que circularam no República Dominicana e Haiti( Ilha de Hispanhola), enquanto que os PV3 selvagens apresentaram uma maior identidade com vírus isolados na Colômbia. Não foi possível,entretanto, estabelecer uma relação direta de ancestralidade entre as amostras.As sequências das regiões não estruturais 2C e 3D não apresentaram uma distribuição uniforme não sendo suficientemente definidas para que pudéssemos inferir o grau de relacionamento filogenético entre as amostras.Devido à indisponibilidade de sequências nucleotíticas de sorotipos de enterovírus não pólio (ENVP) da espécie C que circularam no Brasil e em outros países nos anos 80,não foi possível avaliar com precisão a presença de recombinação entre os polivírus analisados nas regiões 2C e 3D.A caracterização dos EVNP é de extrema importÂncia para a investigação da diversidade de vírus co-circulante e para relacionar o tipo de sintoma clínico com o sorotipo viral envolvido,incluindo a investigação de vias de transmissão de enterovírus durante a ocorrência de surtos,além de contribuir para estudos epidemiológicos e relacionados com a evolução dos enterovírus.


Assuntos
Enterovirus , Epidemiologia , Filogenia , Poliomielite , Poliovirus , Vacinas contra Poliovirus
15.
J Med Virol ; 83(12): 2164-71, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22012725

RESUMO

Aseptic meningitis is one of the most common neurological disorders caused by enteroviruses. Among them, Echovirus 30 (E30) is described as the main etiological agent of many outbreaks and sporadic cases. This study investigated the genomic variability of E30 isolated from the cerebrospinal fluid (CSF) of aseptic meningitis cases that occurred from 1998 to 2008 in Brazil. Over a 10-year period (1998-2008), 302 non-polio enteroviruses were isolated, of which 177 were identified as E30 (58.6%). Phylogenetic analysis of the complete VP1 gene (876 nt) of 48 E30 isolates was performed and compared with additional Brazilian and foreign strains. E30 VP1 sequences segregated into three distinct major groups and seven subgroups, which were linked to the isolation year. In general, sequence divergence among E30 strains ranged from 0.2% to 13.8%. A common direct ancestor for this set of E30 strains was not defined. Brazilian isolates from Group I were related genetically to a 1997 USA isolate and both may have a common origin. Group III representatives showed close relationship to the 2007 Argentinean isolates. The present results complement existing data on the molecular characterization and genetic variability of E30 and may contribute to the understanding of the epidemiology of aseptic meningitis in the region.


Assuntos
Enterovirus Humano B/classificação , Enterovirus Humano B/isolamento & purificação , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Variação Genética , Meningite Asséptica/epidemiologia , Meningite Asséptica/virologia , Brasil/epidemiologia , Proteínas do Capsídeo/genética , Líquido Cefalorraquidiano/virologia , Análise por Conglomerados , Enterovirus Humano B/genética , Genótipo , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Prevalência , RNA Viral/genética , Análise de Sequência de DNA
16.
PLoS One ; 6(8): e23206, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21858030

RESUMO

BACKGROUND: Coxsackievirus A24 variant (CA24v) is the most prevalent viral pathogen associated with acute hemorrhagic conjunctivitis (AHC) outbreaks. Sixteen years after its first outbreak in Brazil, this agent reemerged in 2003 in Brazil, spread to nearly all states and caused outbreaks until 2005. In 2009, a new outbreak occurred in the northeast region of the country. In this study, we performed a viral isolation in cell culture and characterized clinical samples collected from patients presenting symptoms during the outbreak of 2005 in Vitória, Espírito Santo State (ES) and the outbreak of 2009 in Recife, Pernambuco State (PE). We also performed a phylogenetic analysis of worldwide strains and all meaningful Brazilian isolates since 2003. METHODS AND FINDINGS: Sterile cotton swabs were used to collect eye discharges, and all 210 clinical samples were used to inoculate cell cultures. Cytopathic effects in HEp-2 cells were seen in 58 of 180 (32%) samples from Vitória and 3 of 30 (10%) samples from Recife. Phylogenetic analysis based on a fragment of the VP1 and 3C gene revealed that the CA24v causing outbreaks in Brazil during the years 2003, 2004 and 2005 evolved from Asian isolates that had caused the South Korean outbreak of AHC during the summer of 2002. However, the 2009 outbreak of AHC in Pernambuco was originated from the reintroduction of a new CA24v strain that was circulating during 2007 in Asia, where CA24v outbreaks has been continuously reported since 1970. CONCLUSIONS: This study is the first phylogenetic analysis of AHC outbreaks caused by CA24v in Brazil. The results showed that Asian strains of CA24v were responsible for the outbreaks since 1987 and were independently introduced to Brazil in 2003 and 2009. Phylogenetic analysis of complete VP1 gene is a useful tool for studying the epidemiology of enteroviruses associated with outbreaks.


Assuntos
Conjuntivite Hemorrágica Aguda/virologia , Enterovirus Humano C/classificação , Enterovirus Humano C/genética , Filogenia , Proteases Virais 3C , Brasil/epidemiologia , Proteínas do Capsídeo/genética , Linhagem Celular Tumoral , Conjuntivite Hemorrágica Aguda/epidemiologia , Cisteína Endopeptidases/genética , Surtos de Doenças , Enterovirus Humano C/isolamento & purificação , Humanos , Dados de Sequência Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Proteínas Virais/genética
17.
Mem Inst Oswaldo Cruz ; 105(6): 829-33, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20945001

RESUMO

As in humans, sub-clinical infection by arboviruses in domestic animals is common; however, its detection only occurs during epizootics and the silent circulation of some arboviruses may remain undetected. The objective of the present paper was to assess the current circulation of arboviruses in the Nhecolândia sub-region of South Pantanal, Brazil. Sera from a total of 135 horses, of which 75 were immunized with bivalent vaccine composed of inactive Eastern equine encephalitis virus (EEEV) and Western equine encephalitis virus(WEEV) and 60 were unvaccinated, were submitted to thorough viral isolation, reverse transcriptase polymerase chain reaction (RT-PCR) and neutralization tests for Saint Louis encephalitis virus (SLEV), EEEV, WEEV and Mayaro virus (MAYV). No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, the prevalence of neutralizing antibodies in horses older than seven months was 43.7% for SLEV in equines regardless of vaccine status, and 36.4% for WEEV and 47.7% for EEEV in unvaccinated horses. There was no evidence of MAYV infections. The serologic evidence of circulation of arboviruses responsible for equine and human encephalitis, without recent official reports of clinical infections in the area, suggests that the Nhecolândia sub-region in South Pantanal is an important area for detection of silent activity of arboviruses in Brazil.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Encefalite de St. Louis/isolamento & purificação , Encefalomielite Equina/veterinária , Doenças dos Cavalos/epidemiologia , Vacinas Virais/administração & dosagem , Animais , Brasil/epidemiologia , Vírus da Encefalite de St. Louis/imunologia , Encefalomielite Equina/diagnóstico , Encefalomielite Equina/epidemiologia , Encefalomielite Equina/virologia , Feminino , Doenças dos Cavalos/diagnóstico , Cavalos , Masculino , Testes de Neutralização/veterinária , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
18.
Mem. Inst. Oswaldo Cruz ; 105(6): 829-833, Sept. 2010. graf
Artigo em Inglês | LILACS | ID: lil-560671

RESUMO

As in humans, sub-clinical infection by arboviruses in domestic animals is common; however, its detection only occurs during epizootics and the silent circulation of some arboviruses may remain undetected. The objective of the present paper was to assess the current circulation of arboviruses in the Nhecolândia sub-region of South Pantanal, Brazil. Sera from a total of 135 horses, of which 75 were immunized with bivalent vaccine composed of inactive Eastern equine encephalitis virus (EEEV) and Western equine encephalitis virus(WEEV) and 60 were unvaccinated, were submitted to thorough viral isolation, reverse transcriptase polymerase chain reaction (RT-PCR) and neutralization tests for Saint Louis encephalitis virus (SLEV), EEEV, WEEV and Mayaro virus (MAYV). No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, the prevalence of neutralizing antibodies in horses older than seven months was 43.7 percent for SLEV in equines regardless of vaccine status, and 36.4 percent for WEEV and 47.7 percent for EEEV in unvaccinated horses. There was no evidence of MAYV infections. The serologic evidence of circulation of arboviruses responsible for equine and human encephalitis, without recent official reports of clinical infections in the area, suggests that the Nhecolândia sub-region in South Pantanal is an important area for detection of silent activity of arboviruses in Brazil.


Assuntos
Animais , Feminino , Masculino , Anticorpos Antivirais/sangue , Vírus da Encefalite de St. Louis , Encefalomielite Equina/veterinária , Doenças dos Cavalos , Vacinas Virais , Brasil , Vírus da Encefalite de St. Louis/imunologia , Encefalomielite Equina , Encefalomielite Equina , Encefalomielite Equina , Cavalos , Doenças dos Cavalos , Testes de Neutralização/veterinária , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
19.
Rev Inst Med Trop Sao Paulo ; 52(1): 17-24, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20305950

RESUMO

In view of the high circulation of migratory birds and the environmental and climatic conditions which favor the proliferation of arthropods, the Brazilian Pantanal is susceptible to circulation of arboviruses. However, the amount of data concerning arbovirus vectors in this area is scarce; therefore the aim of this study was to conduct a preliminary investigation of Culicidae species in the Nhecolândia Sub-region of South Pantanal, Brazil and their potential importance in the arbovirus transmission. A total of 3684 specimens of mosquitoes were captured, 1689 of which caught in the rainy season of 2007, were divided into 78 pools and submitted to viral isolation, Semi-Nested RT-PCR and Nested RT-PCR, with a view to identifying the most important arboviruses in Brazil. Simultaneously, 70 specimens of ticks found blood-feeding on horses were also submitted to the same virological assays. No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, a total of 22 Culicidae species were identified, ten of which had previously been reported as vectors of important arboviruses. The diversity of species found blood-feeding on human and horse hosts together with the arboviruses circulation previously reported suggest that the Nhecolândia Sub-region of South Pantanal is an important area for arbovirus surveillance in Brazil.


Assuntos
Arbovírus/isolamento & purificação , Culicidae/virologia , Insetos Vetores/virologia , Ixodidae/virologia , Animais , Infecções por Arbovirus/transmissão , Arbovírus/genética , Brasil , Culicidae/classificação , Insetos Vetores/classificação , Ixodidae/classificação , Densidade Demográfica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano
20.
Rev. Inst. Med. Trop. Säo Paulo ; 52(1): 17-24, Jan.-Feb. 2010. tab
Artigo em Inglês | LILACS | ID: lil-540312

RESUMO

In view of the high circulation of migratory birds and the environmental and climatic conditions which favor the proliferation of arthropods, the Brazilian Pantanal is susceptible to circulation of arboviruses. However, the amount of data concerning arbovirus vectors in this area is scarce; therefore the aim of this study was to conduct a preliminary investigation of Culicidae species in the Nhecolândia Sub-region of South Pantanal, Brazil and their potential importance in the arbovirus transmission. A total of 3684 specimens of mosquitoes were captured, 1689 of which caught in the rainy season of 2007, were divided into 78 pools and submitted to viral isolation, Semi-Nested RT-PCR and Nested RT-PCR, with a view to identifying the most important arboviruses in Brazil. Simultaneously, 70 specimens of ticks found blood-feeding on horses were also submitted to the same virological assays. No virus was isolated and viral nucleic-acid detection by RT-PCR was also negative. Nevertheless, a total of 22 Culicidae species were identified, ten of which had previously been reported as vectors of important arboviruses. The diversity of species found blood-feeding on human and horse hosts together with the arboviruses circulation previously reported suggest that the Nhecolândia Sub-region of South Pantanal is an important area for arbovirus surveillance in Brazil.


Regiões como o Pantanal brasileiro, que apresentam fatores como riqueza de fauna silvestre incluindo circulação de aves migratórias e condições ambientais e climáticas favoráveis à proliferação de artrópodes estão potencialmente sujeitas à circulação de arbovírus. Entretanto, poucos trabalhos foram realizados acerca da presença de arbovírus em potenciais vetores no Pantanal. Neste sentido o principal objetivo deste trabalho foi conduzir uma investigação preliminar para presença de arbovírus em amostragens de culicídeos capturados na Sub-região da Nhecolândia no Pantanal Sul. Um total de 3684 mosquitos foi capturado, dos quais 78 grupos compondo uma amostragem de 1789 espécimes foram submetidos às técnicas de isolamento viral e RT-PCR para os mais importantes arbovírus no Brasil. Simultaneamente, 70 espécimes de carrapatos capturados durante hematofagia em cavalos também foram submetidos à pesquisa viral. Não houve isolamento viral em nenhuma amostra analisada e os resultados de detecção de ácido nucléico viral foram também negativos. Entretanto, foram identificadas 22 espécies de culicídeos, dez das quais previamente reportadas como vetores de importantes arbovírus. A competência vetorial de espécies capturadas durante hematofagia em humanos e cavalos aliada ao relato prévio de circulação de arbovírus sugerem a Sub-região da Nhecolândia como uma importante área de vigilância para arbovírus no Centro-Oeste do Brasil.


Assuntos
Animais , Arbovírus/isolamento & purificação , Culicidae/virologia , Insetos Vetores/virologia , Ixodidae/virologia , Infecções por Arbovirus/transmissão , Arbovírus/genética , Brasil , Culicidae/classificação , Insetos Vetores/classificação , Ixodidae/classificação , Densidade Demográfica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano
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