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1.
Viruses ; 12(2)2020 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-31991915

RESUMO

Ticks transmit a wide variety of pathogens including bacteria, parasites and viruses. Over the last decade, numerous novel viruses have been described in arthropods, including ticks, and their characterization has provided new insights into RNA virus diversity and evolution. However, little is known about their ability to infect vertebrates. As very few studies have described the diversity of viruses present in ticks from the Caribbean, we implemented an RNA-sequencing approach on Amblyomma variegatum and Rhipicephalus microplus ticks collected from cattle in Guadeloupe and Martinique. Among the viral communities infecting Caribbean ticks, we selected four viruses belonging to the Chuviridae, Phenuiviridae and Flaviviridae families for further characterization and designing antibody screening tests. While viral prevalence in individual tick samples revealed high infection rates, suggesting a high level of exposure of Caribbean cattle to these viruses, no seropositive animals were detected. These results suggest that the Chuviridae- and Phenuiviridae-related viruses identified in the present study are more likely tick endosymbionts, raising the question of the epidemiological significance of their occurrence in ticks, especially regarding their possible impact on tick biology and vector capacity. The characterization of these viruses might open the door to new ways of preventing and controlling tick-borne diseases.

2.
Infect Genet Evol ; 78: 104130, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31785365

RESUMO

The order Picornavirales is one of the most important viral orders in terms of virus diversity and genome organizations, ranging from a mono- or bi-cistronic expression strategies to the recently described poly-cistronic Polycipiviridae viruses. We report here the description and characterization of a novel picorna-like virus identified in rectal swabs of frugivorous bats in Cambodia that presents an unusual genome organization. Kandabadicivirus presents a unique genome architecture and distant phylogenetic relationship to the proposed Badiciviridae family. These findings highlight a high mosaicism of genome organizations among the Picornavirales.

3.
Front Microbiol ; 10: 2315, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681195

RESUMO

Emerging zoonoses caused by previously unknown agents are one of the most important challenges for human health because of their inherent inability to be predictable, conversely to emergences caused by previously known agents that could be targeted by routine surveillance programs. Emerging zoonotic infections either originate from increasing contacts between wildlife and human populations, or from the geographical expansion of hematophagous arthropods that act as vectors, this latter being more capable to impact large-scale human populations. While characterizing the viral communities from candidate vectors in high-risk geographical areas is a necessary initial step, the need to identify which viruses are able to spill over and those restricted to their hosts has recently emerged. We hypothesized that currently unknown tick-borne arboviruses could silently circulate in specific biotopes where mammals are highly exposed to tick bites, and implemented a strategy that combined high-throughput sequencing with broad-range serological techniques to both identify novel arboviruses and tick-specific viruses in a ticks/mammals interface in Thailand. The virome of Thai ticks belonging to the Rhipicephalus, Amblyomma, Dermacentor, Hyalomma, and Haemaphysalis genera identified numerous viruses, among which several viruses could be candidates for future emergence as regards to their phylogenetic relatedness with known tick-borne arboviruses. Luciferase immunoprecipitation system targeting external viral proteins of viruses identified among the Orthomyxoviridae, Phenuiviridae, Flaviviridae, Rhabdoviridae, and Chuviridae families was used to screen human and cattle Thai populations highly exposed to tick bites. Although no positive serum was detected for any of the six viruses selected, suggesting that these viruses are not infecting these vertebrates, or at very low prevalence (upper estimate 0.017% and 0.047% in humans and cattle, respectively), the virome of Thai ticks presents an extremely rich viral diversity, among which novel tick-borne arboviruses are probably hidden and could pose a public health concern if they emerge. The strategy developed in this pilot study, starting from the inventory of viral communities of hematophagous arthropods to end by the identification of viruses able (or likely unable) to infect vertebrates, is the first step in the prediction of putative new emergences and could easily be transposed to other reservoirs/vectors/susceptible hosts interfaces.

4.
Microbiol Resour Announc ; 8(46)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727698

RESUMO

As part of the characterization of viral communities of Laotian batflies, we report here the sequencing of six nearly complete genome segments of a novel reovirus identified in Laotian batflies that is distantly related to reoviruses recently reported in various Diptera species.

5.
mSphere ; 4(6)2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694898

RESUMO

Jingmenvirus is a recently identified group of segmented RNA viruses phylogenetically linked with unsegmented Flaviviridae viruses. Primarily identified in various tick genera originating in China, Jingmenvirus geographical distribution has rapidly expanded to cover Africa, South America, Caribbean, and Europe. The identification of Jingmen-related viruses in various mammals, including febrile humans, opens the possibility that Jingmenviruses may be novel tick-borne arboviruses. In this study, we aimed at increasing knowledge of the host range, genetic diversity, and geographical distribution of Jingmenviruses by reporting for the first time the identification of Jingmenviruses associated with Rhipicephalus microplus ticks originating in the French Antilles (Guadeloupe and Martinique islands), with Amblyomma testudinarium ticks in Lao PDR, and with Ixodes ricinus ticks in metropolitan France, and from urine of Pteropus lylei bats in Cambodia. Analyses of the relationships between the different Jingmenvirus genomes resulted in the identification of three main phylogenic subclades, each of them containing both tick-borne and mammal-borne strains, reinforcing the idea that Jingmenviruses may be considered as tick-borne arboviruses. Finally, we estimated the prevalence of Jingmenvirus-like infection using luciferase immunoprecipitation assay screening (LIPS) of asymptomatic humans and cattle highly exposed to tick bites. Among 70 French human, 153 Laotian human, and 200 Caribbean cattle sera tested, only one French human serum was found (slightly) positive, suggesting that the prevalence of Jingmenvirus human and cattle infections in these areas is probably low.IMPORTANCE Several arboviruses emerging as new pathogens for humans and domestic animals have recently raised public health concern and increased interest in the study of their host range and in detection of spillover events. Recently, a new group of segmented Flaviviridae-related viruses, the Jingmenviruses, has been identified worldwide in many invertebrate and vertebrate hosts, pointing out the issue of whether they belong to the arbovirus group. The study presented here combined whole-genome sequencing of three tick-borne Jingmenviruses and one bat-borne Jingmenvirus with comprehensive phylogenetic analyses and high-throughput serological screening of human and cattle populations exposed to these viruses to contribute to the knowledge of Jingmenvirus host range, geographical distribution, and mammalian exposure.

6.
J Mol Diagn ; 21(5): 768-781, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416693

RESUMO

Human papillomaviruses (HPVs) are responsible for >99% of cervical cancers. Molecular diagnostic tests based on the detection of viral DNA or RNA have low positive predictive values for the identification of cancer or precancerous lesions. Triage with the Papanicolaou test lacks sensitivity; and even when combined with molecular detection of high-risk HPV, this results in a significant number of unnecessary colposcopies. We have developed a broad-range detection test of HPV transcripts to take a snapshot of the transcriptome of 16 high-risk or putative high-risk HPVs in cervical lesions (HPVs 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 73, and 82). The purpose of this novel molecular assay, named HPV RNA-Seq, is to detect and type HPV-positive samples and to determine a combination of HPV reads at certain specific viral spliced junctions that can better correlate with high-grade cytology, reflecting the presence of precancerous cells. In a proof-of-concept study conducted on 55 patients, starting from cervical smears, we have shown that HPV RNA-Seq can detect papillomaviruses with performances comparable to a widely used HPV reference molecular diagnostic kit; and a combination of the number of sequencing reads at specific early versus late HPV transcripts can be used as a marker of high-grade cytology, with encouraging diagnostic performances as a triage test.

7.
mSphere ; 4(3)2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31167947

RESUMO

The use of high-throughput sequencing (HTS) to identify viruses in biologicals differs from current molecular approaches, since its use enables an unbiased approach to detection without the need to design specific primers to preamplify target sequences. Its broad range of detection and analytical sensitivity make it an important tool to ensure that biologicals are free from adventitious viruses. Similar to other molecular methods, however, identification of viral sequences in cells by HTS does not prove viral infection, since this could reflect carryover of inert viral sequences from reagents or other sources or the presence of transcriptionally inactive cellular sequences. Due to the broad range of detection associated with HTS, the above can potentially be perceived as a drawback for the testing of pharmaceutical biological products using this method. In order to avoid the identification of inert viral sequences, we present a methodology based on metabolic RNA labeling and sequencing, which enables the specific identification of newly synthesized viral RNAs in infected cells, resulting in the ability to unambiguously distinguish active infection by DNA or RNA viruses from inert nucleic acids. In the present study, we report the ability to differentiate Vero cells acutely infected by a single-stranded positive-sense RNA virus (tick-borne encephalitis virus) from cells which have been in contact with nonreplicating virus particles. Additionally, we also found a laboratory contamination by the squirrel monkey retrovirus of our Vero cell line, which was derived from an Old World (African green) monkey, a type of contamination which until now has been identified only in cells derived from primates from the New World.IMPORTANCE The use of high-throughput sequencing (HTS) to identify viral contamination of biological products is extremely sensitive and provides a broad range of detection. Nevertheless, viral sequences identified can also be inert. Examples include contamination resulting from reagents or the presence of inactivated viruses in animal-derived components of the cell culture medium. We therefore developed a method that relies on the sequencing of newly synthesized RNAs, an unequivocal sign of the presence of a transcriptionally active virus. This improvement in the specificity of viral testing increases the acceptability of HTS as a standard test for cells used in manufacturing biologicals and in biotherapies.

8.
Microbiol Resour Announc ; 8(15)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975818

RESUMO

Polycipiviridae is a recently recognized viral family within the order Picornavirales with unusual genome organization and phylogenetic placement. Viruses belonging to this family were only reported from arthropod hosts. We describe here the first full genome of a distant polycipivirus-related virus identified in frugivorous bat stools in Cambodia.

9.
Biologicals ; 59: 29-36, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30992161

RESUMO

The utilization of the current combination of in vitro, in vivo and PCR assays for the identification of adventitious viruses in production cells has a limited range of detection. While Next Generation Sequencing (NGS) has a broader breadth of detection, it is unable to differentiate sequences from replicating viruses versus background inert sequences. In order to improve NGS specificity, we have designed a new NGS approach which targets subsets of viral RNAs only synthesized during cell infection. In order to evaluate the performance of this approach for detecting low levels of adventitious viruses, we selected two difficult virus/cell systems. This included B95-8 cells persistently infected by Human herpesvirus 4 (HHV-4) and serially diluted into HHV-4 negative Ramos cells and Madin-Darby bovine kidney cells with an early infection produced via a low dose of Bovine viral diarrhea virus. We demonstrated that the sensitivity of our RNA NGS approach was equivalent to targeted PCR with an increased specificity for the detection of viral infection. We were also able to identify a previously undetected Murine Leukemia Virus contaminant in Ramos cells. Based on these results, we conclude that this new RNA NGS approach is suitable for conducting viral safety evaluations of cells.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Viral/genética , Análise de Sequência de RNA/métodos , Vírus/genética , Animais , Bovinos , Linhagem Celular , Linhagem Celular Tumoral , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Humanos , Vírus da Leucemia Murina/genética , Vírus da Leucemia Murina/fisiologia , Camundongos , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Viroses/diagnóstico , Viroses/virologia , Vírus/classificação
10.
J Clin Immunol ; 39(1): 81-89, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30607663

RESUMO

The association of immunodeficiency-related vaccine-derived rubella virus (iVDRV) with cutaneous and visceral granulomatous disease has been reported in patients with primary immunodeficiency disorders (PIDs). The majority of these PID patients with rubella-positive granulomas had DNA repair disorders. To support this line of inquiry, we provide additional descriptive data on seven previously reported patients with Nijmegen breakage syndrome (NBS) (n = 3) and ataxia telangiectasia (AT) (n = 4) as well as eight previously unreported patients with iVDRV-induced cutaneous granulomas and DNA repair disorders including NBS (n = 1), AT (n = 5), DNA ligase 4 deficiency (n = 1), and Artemis deficiency (n = 1). We also provide descriptive data on several previously unreported PID patients with iVDRV-induced cutaneous granulomas including cartilage hair hypoplasia (n = 1), warts, hypogammaglobulinemia, immunodeficiency, myelokathexis (WHIM) syndrome (n = 1), MHC class II deficiency (n = 1), Coronin-1A deficiency (n = 1), X-linked severe combined immunodeficiency (X-SCID) (n = 1), and combined immunodeficiency without a molecular diagnosis (n = 1). At the time of this report, the median age of the patients with skin granulomas and DNA repair disorders was 9 years (range 3-18). Cutaneous granulomas have been documented in all, while visceral granulomas were observed in six cases (40%). All patients had received rubella virus vaccine. The median duration of time elapsed from vaccination to the development of cutaneous granulomas was 48 months (range 2-152). Hematopoietic cell transplantation was reported to result in scarring resolution of cutaneous granulomas in two patients with NBS, one patient with AT, one patient with Artemis deficiency, one patient with DNA Ligase 4 deficiency, one patient with MHC class II deficiency, and one patient with combined immunodeficiency without a known molecular etiology. Of the previously reported and unreported cases, the majority share the diagnosis of a DNA repair disorder. Analysis of additional patients with this complication may clarify determinants of rubella pathogenesis, identify specific immune defects resulting in chronic infection, and may lead to defect-specific therapies.


Assuntos
Reparo do DNA/genética , Granuloma/complicações , Granuloma/virologia , Síndromes de Imunodeficiência/complicações , Vírus da Rubéola/patogenicidade , Dermatopatias/etiologia , Dermatopatias/virologia , Adolescente , Ataxia Telangiectasia/genética , Ataxia Telangiectasia/virologia , Criança , Pré-Escolar , Feminino , Granuloma/genética , Cabelo/anormalidades , Cabelo/virologia , Transplante de Células-Tronco Hematopoéticas/métodos , Doença de Hirschsprung/genética , Doença de Hirschsprung/virologia , Humanos , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/virologia , Masculino , Síndrome de Quebra de Nijmegen/genética , Síndrome de Quebra de Nijmegen/virologia , Osteocondrodisplasias/congênito , Osteocondrodisplasias/genética , Osteocondrodisplasias/virologia , Rubéola (Sarampo Alemão)/genética , Rubéola (Sarampo Alemão)/virologia , Pele/virologia , Dermatopatias/genética , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/genética , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/virologia
11.
J Clin Immunol ; 39(1): 112-117, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30680653

RESUMO

PURPOSE: Nitazoxanide was recently reported as having in vitro effectiveness against the rubella virus. Immunodeficiency-related vaccine-derived rubella occurs in some patients who have an inherited immunodeficiency and who received the MMR vaccine. This study investigated the in vivo effectiveness of nitazoxanide therapy. METHODS: This is a retrospective analysis of seven patients treated with nitazoxanide as salvage therapy for immunodeficiency-related vaccine-derived rubella infection. The patients were recruited from an ongoing rubella detection surveillance project. RESULTS: Seven patients with persistent rubella were treated with nitazoxanide and one demonstrated significant clinical improvement. Two additional patients exhibited diminished viral capsid production with one patient having transient slowing of progression. The cohort overall generally had low T cell counts and had a high burden of comorbidities. There were three deaths. Two deaths were from PML and one was related to hematopoietic stem cell transplantation. CONCLUSIONS: Nitazoxanide has limited in vivo anti-viral effects for immunodeficiency-related vaccine-derived rubella. Most patients did not exhibit clinical improvement.


Assuntos
Granuloma/tratamento farmacológico , Síndromes de Imunodeficiência/virologia , Vírus da Rubéola/efeitos dos fármacos , Rubéola (Sarampo Alemão)/tratamento farmacológico , Tiazóis/uso terapêutico , Adolescente , Criança , Pré-Escolar , Feminino , Granuloma/virologia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Rubéola (Sarampo Alemão)/virologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/virologia , Vacinação/métodos
12.
Arch Virol ; 164(3): 747-755, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30631958

RESUMO

A variety of viruses can cause acute flaccid paralysis (AFP). However, the causative agent, sometimes, remains undetermined. Metagenomics helps in identifying viruses not diagnosed by conventional methods. Stool samples from AFP (n = 104) and non-AFP (n = 114) cases that tested enterovirus-negative by WHO standard methods were investigated. A metagenomics approach, first used on five pools of four samples each, revealed the presence of adenovirus sequences. Amplification in A549 cells and full-genome sequencing were used for complete virus identification and for designing a PCR assay to screen individual related samples. Metagenomic analysis showed that adenovirus sequences that were closely to the A31 and A61 genotypes were the most abundant. Two out of the corresponding 20 individual samples were found positive by PCR, and isolates were obtained in cell culture. Phylogenetic analysis based on complete genome sequences showed that the viruses belong to HAdV-A31 genotype (98-100% nucleotide sequence identity). PCR analysis of stool samples from all AFP and non-AFP cases revealed that a larger proportion of the positive samples were from AFP cases (17.3%) than from non-AFP cases (2.4%). These results open the way to studies aiming to test a possible role of HAdV-A31 in the pathogenesis of AFP.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Paraplegia/virologia , Adenovírus Humanos/classificação , Adolescente , Criança , Pré-Escolar , Fezes/virologia , Genótipo , Humanos , Lactente , Metagenômica , Filogenia , Tunísia
13.
Viruses ; 10(10)2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332784

RESUMO

A key step for broad viral detection using high-throughput sequencing (HTS) is optimizing the sample preparation strategy for extracting viral-specific nucleic acids since viral genomes are diverse: They can be single-stranded or double-stranded RNA or DNA, and can vary from a few thousand bases to over millions of bases, which might introduce biases during nucleic acid extraction. In addition, viral particles can be enveloped or non-enveloped with variable resistance to pre-treatment, which may influence their susceptibility to extraction procedures. Since the identity of the potential adventitious agents is unknown prior to their detection, efficient sample preparation should be unbiased toward all different viral types in order to maximize the probability of detecting any potential adventitious viruses using HTS. Furthermore, the quality assessment of each step for sample processing is also a critical but challenging aspect. This paper presents our current perspectives for optimizing upstream sample processing and library preparation as part of the discussion in the Advanced Virus Detection Technologies Interest group (AVDTIG) The topics include: use of nuclease treatment to enrich for encapsidated nucleic acids, techniques for amplifying low amounts of virus nucleic acids, selection of different extraction methods, relevant controls, the use of spike recovery experiments, and quality control measures during library preparation.


Assuntos
Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Manejo de Espécimes/métodos , Vírus/isolamento & purificação , Animais , DNA Viral/genética , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala/tendências , Humanos , RNA Viral/genética , Vírion/genética , Vírion/isolamento & purificação , Viroses/virologia , Vírus/genética
14.
Emerg Infect Dis ; 24(8): 1435-1443, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30014832

RESUMO

We investigated the cause of seasonal outbreaks of pediatric acute encephalitis-like syndrome associated with litchi harvests (May-July) in northern Vietnam since 2008. Nineteen cerebrospinal fluid samples were positive for human enterovirus B, and 8 blood samples were positive for hypoglycemic toxins present in litchi fruits. Patients who were positive for hypoglycemic toxins had shorter median times between disease onset and admission, more reports of seizures, more reports of hypoglycemia (glucose level <3 mmol/L), lower median numbers of leukocytes in cerebrospinal fluid, and higher median serum levels of alanine aminotransferase and aspartate transaminase than did patients who were positive for enteroviruses. We suggest that children with rapidly progressing acute encephalitis-like syndrome at the time of the litchi harvest have intoxication caused by hypoglycemic toxins, rather than viral encephalitis, as previously suspected. These children should be urgently treated for life-threatening hypoglycemia.


Assuntos
Encefalopatia Aguda Febril/epidemiologia , Encefalopatia Aguda Febril/etiologia , Infecções por Enterovirus/complicações , Enterovirus , Criança , Pré-Escolar , Infecções por Enterovirus/epidemiologia , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Estações do Ano , Vietnã/epidemiologia
15.
Infect Genet Evol ; 61: 151-154, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29592838

RESUMO

Usutu virus (USUV) was detected in 11 Culex pipiens mosquito pools collected in 2015 in Camargue (France) using quantitative real-time RT-PCR assays. Phylogenetic analysis of recovered virus sequences identified USUV lineages Africa 2 and Africa 3, demonstrating the simultaneous occurrence of different strains within the mosquito population. This is the first report on USUV in mosquitoes from France that concurrently accompanied the emergence of Usutu virus in blackbirds and a human case in France during 2015/2016.


Assuntos
Culex/virologia , Infecções por Flavivirus/veterinária , Infecções por Flavivirus/virologia , Flavivirus/genética , Animais , Feminino , França , Filogenia , RNA Viral/análise , RNA Viral/genética
16.
Nat Commun ; 8(1): 1268, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29097653

RESUMO

Exposure of human populations to bovine spongiform encephalopathy through contaminated food has resulted in <250 cases of variant Creutzfeldt-Jakob disease (vCJD). However, more than 99% of vCJD infections could have remained silent suggesting a long-term risk of secondary transmission particularly through blood. Here, we present experimental evidence that transfusion in mice and non-human primates of blood products from symptomatic and non-symptomatic infected donors induces not only vCJD, but also a different class of neurological impairments. These impairments can all be retransmitted to mice with a pathognomonic accumulation of abnormal prion protein, thus expanding the spectrum of known prion diseases. Our findings suggest that the intravenous route promotes propagation of masked prion variants according to different mechanisms involved in peripheral replication.


Assuntos
Transfusão de Sangue , Síndrome de Creutzfeldt-Jakob/transmissão , Reação Transfusional , Animais , Doenças Assintomáticas , Doadores de Sangue , Bovinos , Síndrome de Creutzfeldt-Jakob/metabolismo , Encefalopatia Espongiforme Bovina/transmissão , Feminino , Humanos , Macaca fascicularis , Masculino , Camundongos , Doenças Priônicas/classificação , Doenças Priônicas/metabolismo , Doenças Priônicas/transmissão , Proteínas Priônicas/metabolismo
17.
Emerg Microbes Infect ; 6(5): e35, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28536430

RESUMO

Acute meningoencephalitis (AME) is associated with considerable morbidity and mortality in children in developing countries. Clinical specimens were collected from children presenting with AME at two Cambodian paediatric hospitals to determine the major aetiologies associated with AME in the country. Cerebrospinal fluid (CSF) and blood samples were screened by molecular and cell culture methods for a range of pathogens previously associated with AME in the region. CSF and serum (acute and convalescent) were screened for antibodies to arboviruses such as Japanese encephalitis virus (JEV), dengue virus (DENV), and chikungunya virus (CHIKV). From July 2010 through December 2013, 1160 children (one month to 15 years of age) presenting with AME to two major paediatric hospitals were enroled into the study. Pathogens associated with AME were identified using molecular diagnostics, cell culture and serology. According to a diagnostic algorithm, a confirmed or highly probable aetiologic agent was detected in 35.0% (n=406) of AME cases, with a further 9.2% (total: 44.2%, n=513) aetiologies defined as suspected. JEV (24.4%, n=283) was the most commonly identified pathogen followed by Orientia tsutsugamushi (4.7%, n=55), DENV (4.6%, n=53), enteroviruses (3.5%, n=41), CHIKV (2.0%, n=23) and Streptococcus pneumoniae (1.6%, n=19). The majority of aetiologies identified for paediatric AME in Cambodia were vaccine preventable and/or treatable with appropriate antimicrobials.


Assuntos
Vírus Chikungunya/isolamento & purificação , Vírus da Dengue/isolamento & purificação , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Meningoencefalite/microbiologia , Meningoencefalite/virologia , Doença Aguda , Adolescente , Anticorpos Antivirais/sangue , Camboja/epidemiologia , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus Chikungunya/patogenicidade , Criança , Pré-Escolar , Dengue/diagnóstico , Dengue/epidemiologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Vírus da Dengue/patogenicidade , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Encefalite Japonesa/diagnóstico , Encefalite Japonesa/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningoencefalite/diagnóstico , Meningoencefalite/epidemiologia , Técnicas de Diagnóstico Molecular , Orientia tsutsugamushi/genética , Orientia tsutsugamushi/isolamento & purificação , Tifo por Ácaros/diagnóstico , Tifo por Ácaros/epidemiologia
18.
J Vet Diagn Invest ; 29(3): 305-311, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28363267

RESUMO

Swine pasivirus 1 (SPaV-1) was first detected in the feces of healthy pigs in France as a new species in family Picornaviridae. We investigated the presence, distribution, and genetic variability of this virus in 7 geographic areas with intensive pig breeding farms in eastern Romania. A total of 564 porcine specimens, including 82 fecal specimens and 482 pools of organs, were collected from healthy pigs in different stages of production from pathogen-free swine farming units. The virus was found in 6 of 7 areas investigated. Of the 564 samples analyzed, 218 were positive for SPaV-1, with the highest prevalence of the virus in organ homogenates (39% positive) followed by feces (37% positive). The highest susceptibility to infection was found in nurseries (50% positive in both the first and second months of feeding). Sequencing analysis of VP0 revealed 3 different Romanian sequences. The phylogenetic investigations suggest that the Romanian sequences cluster with other Pasivirus strains selected from the GenBank database, forming a separate clade from other Picornaviridae genera and defining the described Pasivirus.


Assuntos
Infecções por Picornaviridae/veterinária , Picornaviridae/isolamento & purificação , Doenças dos Suínos/epidemiologia , Animais , Fazendas , Fezes/virologia , Filogenia , Picornaviridae/classificação , Picornaviridae/genética , Infecções por Picornaviridae/epidemiologia , Infecções por Picornaviridae/virologia , Prevalência , Romênia/epidemiologia , Organismos Livres de Patógenos Específicos , Suínos , Doenças dos Suínos/etiologia , Doenças dos Suínos/virologia
20.
Viruses ; 9(1)2017 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-28085120

RESUMO

Various methods exist to detect an astrovirus infection. Current methods include electron microscopy (EM), cell culture, immunoassays, polymerase chain reaction (PCR) and various other molecular approaches that can be applied in the context of diagnostic or in surveillance studies. With the advent of metagenomics, novel human astrovirus (HAstV) strains have been found in immunocompromised individuals in association with central nervous system (CNS) infections. This work reviews the past and current methods for astrovirus detection and their uses in both research laboratories and for medical diagnostic purposes.


Assuntos
Infecções por Astroviridae/diagnóstico , Astroviridae/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , Técnicas Microbiológicas/métodos , Humanos
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