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1.
Pediatr Infect Dis J ; 40(4): 300-305, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33230056

RESUMO

BACKGROUND: Infants with medical risk conditions are vulnerable to childhood infections including acute gastroenteritis (AGE). To guide prevention programs, we quantified AGE incidence, severity and virus prevalence among medical risk infants in the Netherlands. METHODS: This prospective cohort-study was part of the RIVAR-project recruiting infants with prematurity, low birth weight or severe congenital conditions in 13 hospitals. Follow-up included 18 monthly health questionnaires detailing AGE symptoms and healthcare usage. Parents were also instructed to notify when an infant developed AGE, to collect a stool sample and complete a daily severity score (Modified Vesikari Severity). Stool samples were analyzed by real-time polymerase chain reaction for rotavirus, norovirus, adenovirus and astrovirus. RESULTS: Between November 2014 and October 2017, 631 infants participated during 9125 person-months of observation. In total, 559 episodes were identified. The mean AGE incidence rate was 73.5 per 100 person-years (PY) (95% confidence interval: 67.6-79.9) and increased with age [incidence rate: 48.3 (39.8-58.3) vs. 80.2 (73.0-88.1)/100 PY for ages 1-5 vs. 6-18 months, respectively]. Healthcare was attended for 38.1% (213/559) and 26.8% (68/254) were classified as severe based on the Modified Vesikari Severity. Stool samples were obtained from 254 AGE episodes. Norovirus was identified in 65 (25.6%) and rotavirus in 44 (17.7%). Adenovirus and astrovirus together accounted for 8.3% (N = 21). Severe AGE occurred most frequently in rotavirus positive episodes. CONCLUSION: The observed AGE incidence, severity and healthcare usage among medical risk infants confirms substantial disease burden. Norovirus and rotavirus are the dominant pathogens and severe episodes occurred most frequently in children with rotavirus infection. AGE prevention in medical risk infants should be prioritized.


Assuntos
Efeitos Psicossociais da Doença , Diarreia/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Vírus/genética , Doença Aguda/epidemiologia , Diarreia/epidemiologia , Fezes/virologia , Humanos , Incidência , Lactente , Países Baixos/epidemiologia , Prevalência , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Vírus/classificação , Vírus/isolamento & purificação , Vírus/patogenicidade
2.
Diagn Microbiol Infect Dis ; 97(4): 115061, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32585545

RESUMO

Timely identification of etiological agents of enteric infections is necessary to reduce the burden of infantile diarrheal mortality. Nucleic acid amplification-based detection methods offer a quick, reliable way for diagnosis of microbes in clinical specimens. This study was undertaken to evaluate an easy-to-use, cost-effective multiplex conventional reverse-transcription polymerase chain reaction (RT-PCR) assay developed at the Indian Council of Medical Research-National Institute of Cholera and Enteric Diseases virology laboratory to identify 4 common enteric viruses (rotavirus, norovirus, adenovirus, astrovirus) in stool samples from patients who were being evaluated for acute diarrhea. On comparison with a commercially available real-time PCR method, significant agreement in sensitivity and specificity was observed. Though the turnaround time for RT-PCR was 6-8 h compared to 5-6 h for real-time PCR, the real-time PCR has high test cost (approximately 28 USD/2000 INR) for Fast-Track Diagnostics kit-based quantitative RT-PCR versus 6 USD or 400 INR for conventional multiplex RT-PCR/sample. Thus, the conventional RT-PCR method is expected to be adaptable at local hospitals and health cares in resource-poor settings.


Assuntos
Técnicas de Laboratório Clínico/métodos , Gastroenterite/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Vírus/isolamento & purificação , Técnicas de Laboratório Clínico/economia , Técnicas de Laboratório Clínico/normas , Coinfecção/diagnóstico , Coinfecção/virologia , Diarreia/diagnóstico , Diarreia/virologia , Fezes/virologia , Gastroenterite/virologia , Humanos , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/economia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Sensibilidade e Especificidade , Vírus/classificação , Vírus/genética
3.
Influenza Other Respir Viruses ; 14(4): 465-469, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32153113

RESUMO

This study was conducted to determine the prevalence of respiratory viral infections (RVI) in persons living with HIV (PLH) admitted with a respiratory complaint using real-time reverse transcription polymerase chain reaction and primer-independent next-generation sequencing (NGS). Of 82 subjects, respiratory viruses were the most common pathogen identified in 27 (33%), followed by fungus and bacteria in 8 (10%) and 4 (5%) subjects, respectively. Among subjects with RVI, 11 (41%) required ICU admission and 16 (59%) required mechanical ventilation. The proportion of respiratory viruses identified, and the associated complicated hospital course highlights the significant role that RVIs play in the lung health of PLH.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Vírus/genética , Efeitos Psicossociais da Doença , Feminino , HIV/genética , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/epidemiologia , Prevalência , Estudos Prospectivos , Infecções Respiratórias/complicações , Centros de Atenção Terciária/estatística & dados numéricos , Vírus/classificação , Vírus/isolamento & purificação , Vírus/patogenicidade
4.
Curr Top Microbiol Immunol ; 424: 75-83, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31650236

RESUMO

Infectious disease emergence into humans from animals or the environment occurs primarily due to genetic changes in the microbe through mutation or re-assortment making it either more transmissible or virulent or through a change in the disease "ecosystem". Research into infectious disease emergence can be grouped into different strategic approaches. One strategic approach is to study a specific or model disease system to understand the ecology of an infectious disease and how is transmitted and propagated through the environment and different hosts and then extrapolate that disease system knowledge to related pathogens. The other strategic approach follows the genomics and phylogenetics-tracking how pathogens are evolving and changing at the amino acid level. Here we argue that for understanding complex zoonotic diseases and for the purposes of preventing emergence and re-emergence into humans, that the Return on Investment be considered for the best research strategy.


Assuntos
Doenças Transmissíveis/economia , Doenças Transmissíveis/epidemiologia , Ecossistema , Monitoramento Epidemiológico , Filogenia , Vírus/classificação , Vírus/patogenicidade , Animais , Doenças Transmissíveis/classificação , Doenças Transmissíveis/virologia , Humanos , Investimentos em Saúde , Vírus/genética , Zoonoses/virologia
5.
J Clin Virol ; 106: 13-17, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007137

RESUMO

BACKGROUND: Respiratory infections are common reasons for hospital admission, and are associated with enormous economic burden due to significant morbidity and mortality. The wide spectrum of microbial agents underlying the pathology renders the diagnosis of respiratory infections challenging. Molecular diagnostics offer an advantage to the current serological and culture-based methods in terms of sensitivity, coverage, hands-on time, and time to results. OBJECTIVES: This study aimed to compare the clinical performance of three commercial kits for respiratory viral detection. STUDY DESIGN: The performance of FilmArray Respiratory Panel, AnyplexII RV16, and Argene was compared using clinical respiratory samples (n = 224, comprising 189 nasopharyngeal swabs in Universal Transport Medium (UTM) and 35 endotracheal aspirates), based on common overlapping targets across the platforms. Influenza A "equivocal" and "no-subtype" samples by FilmArray were further compared to a laboratory-developed Influenza A/B test. RESULTS AND CONCLUSIONS: The overall performance of all three platforms appeared to be comparable with regards to sensitivities (95.8-97.9%) and specificities (96.1-98.0%), detection of coinfections, and distinguishment of influenza from non-influenza cases. "Equivocal" and "no-subtype" samples by FilmArray mostly represented weak Influenza A by laboratory-developed test. Lower respiratory tract samples had comparable final-run success-rates and discordant-rates as compared to UTM. Coronavirus HKU1, which was not targeted by AnyplexII RV16, were detected as OC43. The expected test volume would be the main determinant for the selection of platform. Among the platforms, the FilmArray is the most automated but is of the lowest-throughput and has the highest reagent cost.


Assuntos
Técnicas de Diagnóstico Molecular , Kit de Reagentes para Diagnóstico/normas , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Vírus/genética , Coinfecção/diagnóstico , Coinfecção/virologia , Enterovirus/genética , Enterovirus/isolamento & purificação , Hospitalização , Humanos , Influenza Humana/diagnóstico , Reação em Cadeia da Polimerase Multiplex , Nasofaringe/virologia , Kit de Reagentes para Diagnóstico/economia , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Sensibilidade e Especificidade , Vírus/classificação , Vírus/isolamento & purificação
6.
Retrovirology ; 15(1): 19, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29402305

RESUMO

BACKGROUND: Simian immunodeficiency viruses (SIVs) of chimpanzees and gorillas from Central Africa crossed the species barrier at least four times giving rise to human immunodeficiency virus type 1 (HIV-1) groups M, N, O and P. The paradigm of non-pathogenic lentiviral infections has been challenged by observations of naturally infected chimpanzees with SIVcpz associated with a negative impact on their life span and reproduction, CD4+ T-lymphocyte loss and lymphoid tissue destruction. With the advent and dissemination of new generation sequencing technologies, novel promising markers of immune deficiency have been explored in human and nonhuman primate species, showing changes in the microbiome (dysbiosis) that might be associated with pathogenic conditions. The aim of the present study was to identify and compare enteric viromes of SIVgor-infected and uninfected gorillas using noninvasive sampling and ultradeep sequencing, and to assess the association of virome composition with potential SIVgor pathogenesis in their natural hosts. RESULTS: We analyzed both RNA and DNA virus libraries of 23 fecal samples from 11 SIVgor-infected (two samples from one animal) and 11 uninfected western lowland gorillas from Campo-Ma'an National Park (CP), in southwestern Cameroon. Three bacteriophage families (Siphoviridae, Myoviridae and Podoviridae) represented 67.5 and 68% of the total annotated reads in SIVgor-infected and uninfected individuals, respectively. Conversely, mammalian viral families, such as Herpesviridae and Reoviridae, previously associated with gut- and several mammalian diseases were significantly more abundant (p < 0.003) in the SIVgor-infected group. In the present study, we analyzed, for the first time, the enteric virome of gorillas and their association with SIVgor status. This also provided the first evidence of association of specific mammalian viral families and SIVgor in a putative dysbiosis context. CONCLUSIONS: Our results suggested that viromes might be potentially used as markers of lentiviral disease progression in wild gorilla populations. The diverse mammalian viral families, herein described in SIVgor-infected gorillas, may play a pivotal role in a disease progression still unclear in these animals but already well characterized in pathogenic lentiviral infections in other organisms. Larger sample sets should be further explored to reduce intrinsic sampling variation.


Assuntos
Disbiose/virologia , Microbioma Gastrointestinal , Gorilla gorilla/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus/classificação , Animais , Animais Selvagens , Anticorpos Antivirais/sangue , Antígenos Virais , Biodiversidade , Análise por Conglomerados , Disbiose/etiologia , Fezes/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/complicações , Vírus da Imunodeficiência Símia/patogenicidade , Carga Viral , Vírus/genética
7.
PLoS One ; 13(1): e0190938, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29351302

RESUMO

When human samples are sequenced, many assembled contigs are "unknown", as conventional alignments find no similarity to known sequences. Hidden Markov models (HMM) exploit the positions of specific nucleotides in protein-encoding codons in various microbes. The algorithm HMMER3 implements HMM using a reference set of sequences encoding viral proteins, "vFam". We used HMMER3 analysis of "unknown" human sample-derived sequences and identified 510 contigs distantly related to viruses (Anelloviridae (n = 1), Baculoviridae (n = 34), Circoviridae (n = 35), Caulimoviridae (n = 3), Closteroviridae (n = 5), Geminiviridae (n = 21), Herpesviridae (n = 10), Iridoviridae (n = 12), Marseillevirus (n = 26), Mimiviridae (n = 80), Phycodnaviridae (n = 165), Poxviridae (n = 23), Retroviridae (n = 6) and 89 contigs related to described viruses not yet assigned to any taxonomic family). In summary, we find that analysis using the HMMER3 algorithm and the "vFam" database greatly extended the detection of viruses in biospecimens from humans.


Assuntos
Microbiota , Vírus/genética , Vírus/isolamento & purificação , Algoritmos , Biologia Computacional , Mapeamento de Sequências Contíguas/estatística & dados numéricos , Bases de Dados de Proteínas/estatística & dados numéricos , Humanos , Cadeias de Markov , Metagenômica/estatística & dados numéricos , Filogenia , Proteínas Virais/genética , Vírus/classificação
8.
Int J Cancer ; 141(12): 2498-2504, 2017 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-28840939

RESUMO

Most cancer forms known to be caused by viruses are increased among the immunosuppressed, but several cancer forms without established viral etiology are also increased, notably nonmelanoma skin carcinoma (NMSC). We followed all 13,429 solid organ transplantation patients in Sweden for cancer occurrence after transplantation. We requested these tumor specimens and sequenced the first 89 specimens received (62 NMSCs, 27 other cancers). The sequences were analyzed for viruses based on two bioinformatics algorithms (paracel-blast (sensitive for detection of known viruses) and hidden Markov model (HMM; sensitive for distantly related viruses)). Among the 62 NMSCs, the virus family detected in the largest proportion of specimens was Mimiviridae (9/62 NMSCs). The majority of the virus-related reads belonged to Papillomaviridae. The HMM analysis identified 86 additional previously not described viral contigs related to 11 virus families, with reads related to Mimiviridae being the most common (detected in 28/62 NMSCs) with the most prevalent contig (Mimivirus SE906, 1937 bp) detected in 17/62 NMSCs. Among the 27 other cancers, viral sequences were detected in only 5 specimens by blast analysis, compared to in all 27 specimens by HMM (Mimiviridae, Poxviridae, Phycodnaviridae and virus-related sequences yet unclassified to any family). 99% of the virus reads belonged to a single previously not described sequence (Mimivirus SE996, 911 bp). A multitude of viruses is readily detectable in specimens with cancers occurring among the immunosuppressed, with sequences related to Mimiviridae being the most prevalent. Further research would be needed to elucidate the biological significance of the viruses.


Assuntos
Neoplasias/imunologia , Transplante de Órgãos/efeitos adversos , Análise de Sequência de DNA/métodos , Viroses/epidemiologia , Vírus/classificação , Algoritmos , Biologia Computacional/métodos , Humanos , Hospedeiro Imunocomprometido , Cadeias de Markov , Mimiviridae/genética , Mimiviridae/isolamento & purificação , Neoplasias/virologia , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Suécia , Vírus/genética
10.
Hum Vaccin Immunother ; 12(9): 2422-40, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27269963

RESUMO

This systematic review evaluated the epidemiology of community-acquired pneumonia in children <6 y of age within 90 developing and newly industrialized countries. Literature searches (1990-2011), based on MEDLINE, EMBASE, Cochrane, CAB Global Health, WHO, UNICEF, country-specific websites, conferences, health-technology-assessment agencies, and the reference lists of included studies, yielded 8,734 records; 62 of 340 studies were included in this review. The highest incidence rate among included studies was 0.51 episodes/child-year, for children <5 y of age in Bangladesh. The highest prevalence was in Chinese children <6 months of age (37.88%). The main bacterial pathogens were Streptococcus pneumoniae, Haemophilus influenzae and Mycoplasma pneumoniae and the main viral pathogens were respiratory syncytial virus, adenovirus and rhinovirus. Community-acquired pneumonia remains associated with high rates of morbidity and mortality. Improved and efficient surveillance and documentation of the epidemiology and burden of community-acquired pneumonia across various geographical regions is warranted.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Pneumonia Bacteriana/epidemiologia , Pneumonia Viral/epidemiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Pré-Escolar , Países Desenvolvidos , Países em Desenvolvimento , Humanos , Incidência , Lactente , Recém-Nascido , Pneumonia Bacteriana/mortalidade , Pneumonia Viral/mortalidade , Prevalência , Vírus/classificação , Vírus/isolamento & purificação
11.
Influenza Other Respir Viruses ; 10(5): 386-93, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27012372

RESUMO

BACKGROUND: Severe acute respiratory illness (SARI) is recognized as an important cause of morbidity, mortality, and hospitalization among children in developing countries. Little is known, however, in tropical countries like Cameroon about the cause and seasonality of respiratory infections, especially in hospitalized settings. OBJECTIVES: Our study investigates the viral etiology and seasonality of SARI in hospitalized children in Yaounde, Cameroon. METHODS: Prospective clinic surveillance was conducted to identify hospitalized children aged ≤15 years presenting with respiratory symptoms ≤5-day duration. Demographic and clinical data, and respiratory specimens were collected. Nasopharyngeal samples were tested for 17 respiratory viruses using a multiplex polymerase chain reaction. The viral distribution and demographic data were statistically analyzed. RESULTS: From September 2011 through September 2013, 347 children aged ≤15 years were enrolled. At least one virus was identified in each of 65·4% children, of which 29·5% were coinfections; 27·3% were positive for human adenovirus (hAdV), 13·2% for human respiratory syncytial virus (hRSV), 11·5% for rhinovirus/enterovirus (RV/EV), 10·6% for human bocavirus (hBoV), 9·8% for influenza virus (Inf), 6·6% for human parainfluenza virus (hPIV), 5·7% for human coronavirus (hCoV), and 2·3% for human metapneumovirus (hMPV). While hRSV showed seasonal patterns, hAdV and RV/EV were detected throughout the year and no evident temporal patterns were observed for the remaining viruses. CONCLUSION: Respiratory viruses were associated with a high burden of hospitalizations among children in Cameroon. Nevertheless, additional studies evaluating asymptomatic Cameroonian children will be important in understanding the relationship between viral carriage and disease.


Assuntos
Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Vírus/isolamento & purificação , Doença Aguda/epidemiologia , Adolescente , Camarões/epidemiologia , Portador Sadio/epidemiologia , Portador Sadio/virologia , Criança , Pré-Escolar , Coinfecção/virologia , Efeitos Psicossociais da Doença , Monitoramento Epidemiológico , Feminino , Hospitalização , Bocavirus Humano/genética , Bocavirus Humano/isolamento & purificação , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase Multiplex , Nasofaringe/virologia , Estudos Prospectivos , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Estações do Ano , Vírus/classificação , Vírus/genética
12.
Crit Rev Microbiol ; 42(6): 883-904, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26585708

RESUMO

The EU Marine Strategy Framework Directive 2008/56/EC (MSFD) defines a framework for Community actions in the field of marine environmental policy in order to achieve and/or maintain the Good Environmental Status (GES) of the European seas by 2020. Microbial assemblages (from viruses to microbial-sized metazoa) provide a major contribution to global biodiversity and play a crucial role in the functioning of marine ecosystems, but are largely ignored by the MSFD. Prokaryotes are only seen as "microbial pathogens," without defining their role in GES indicators. However, structural or functional prokaryotic variables (abundance, biodiversity and metabolism) can be easily incorporated into several MSFD descriptors (i.e. D1. biodiversity, D4. food webs, D5. eutrophication, D8. contaminants and D9. contaminants in seafood) with beneficial effects. This review provides a critical analysis of the current MSFD descriptors and illustrates the reliability and advantages of the potential incorporation of some prokaryotic variables within the set of indicators of marine environmental quality. Following a cost/benefit analysis against scientific and economic criteria, we conclude that marine microbial components, and particularly prokaryotes, are highly effective for detecting the effects of anthropogenic pressures on marine environments and for assessing changes in the environmental health status. Thus, we recommend the inclusion of these components in future implementations of the MSFD.


Assuntos
Bactérias/classificação , Água do Mar/microbiologia , Água do Mar/virologia , Vírus/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Europa (Continente) , Oceanos e Mares , Filogenia , Vírus/genética , Vírus/isolamento & purificação
13.
J Appl Microbiol ; 119(6): 1729-39, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26473649

RESUMO

AIMS: To assess the removal of viruses through the multiple steps of wastewater treatment in a full-scale municipal wastewater treatment plant in Alberta, Canada. METHODS AND RESULTS: Samples were collected after each of the five treatment steps for a period of 16 months. The amount of viruses and their infectivity were analysed using real-time quantitative PCR (qPCR) and integrated viral cell culture (ICC), respectively. Bacterial indicator Escherichia coli was also tested using membrane filtration. Seven viruses including Norovirus (NoV), Rotavirus (RV), Sapovirus (SaV), Astrovirus (AsV), Adenovirus (AdV), Enterovirus (EV) and JC virus (JCV) were detected in 16 primary effluents in which infectious viruses were present. Different treatment steps showed various efficiencies in virus removal, with membrane ultrafiltration as the most effective at 4·6-7·0 log reduction. CONCLUSIONS: We observed high prevalence of viruses in raw wastewater and different viral reduction after various treatment steps. The discharge of treated wastewater with infectious viruses represents potential risks to human, animal and environmental health. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a comprehensive assessment of the removal of NoV, RV, SaV, AsV, AdV, EV, JCV and Reovirus from wastewater by current procedures of municipal wastewater treatment and discusses the applicability of various viruses as viral indicators for water quality.


Assuntos
Vírus , Águas Residuárias/microbiologia , Purificação da Água , Alberta , Humanos , Viroses/virologia , Vírus/classificação , Vírus/genética , Vírus/isolamento & purificação
14.
J Microbiol Methods ; 118: 93-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342434

RESUMO

OBJECTIVES: We aim to develop a multiplex real-time PCR assay to detect the most common pathogens causing community outbreaks of diarrhea. METHODS: Four reaction systems of fluorescence dye-based real-time PCR assay were performed to amplify genes of norovirus, sapovirus, rotavirus, astrovirus, adenovirus, Campylobacter jejuni, Yersinia enterocolitica, Vibrio parahaemolyticus, Salmonella spp., Escherichia coli, and Shigella spp. PCR products of each pathogen were identified by characteristic peaks in melting curves. RESULTS: The assay was able to achieve detection limit of 50 copies/reaction for each individual virus target, and 140-500CFU/mL for each individual bacterium target. A total of 122 clinical specimens from hospitalized children with acute diarrhea were used to evaluate the assay. The clinical sensitivity was very similar to that of reference methods. Norovirus genogroup II revealed the highest detectable rate (45/122, 36.9%). Coinfection was found in 28 out of 122 (23%) clinical specimens. CONCLUSION: This assay proved to be a cost-effective, sensitive and reliable method for simultaneous detection of enteric viruses and bacteria.


Assuntos
Bactérias/isolamento & purificação , Infecções Comunitárias Adquiridas/diagnóstico , Diarreia/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Vírus/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/virologia , Análise Custo-Benefício , Diarreia/microbiologia , Diarreia/virologia , Humanos , Lactente , Recém-Nascido , Técnicas de Diagnóstico Molecular/economia , Reação em Cadeia da Polimerase em Tempo Real/economia , Sensibilidade e Especificidade , Temperatura de Transição , Vírus/classificação , Vírus/genética
15.
J Agric Food Chem ; 62(49): 12067-74, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25389086

RESUMO

Functional small RNAs, such as short interfering RNAs (siRNAs) and microRNAs (miRNAs), exist in freshly consumed fruits and vegetables. These siRNAs can be derived either from endogenous sequences or from viruses that infect them. Symptomatic tomatoes, watermelons, zucchini, and onions were purchased from grocery stores and investigated by small RNA sequencing. By aligning the obtained small RNA sequences to sequences of known viruses, four different viruses were identified as infecting these fruits and vegetables. Many of these virally derived small RNAs along with endogenous small RNAs were found to be highly complementary to human genes. However, the established history of safe consumption of these vegetables suggests that this sequence homology has little biological relevance. By extension, these results provide evidence for the safe use by humans and animals of genetically engineered crops using RNA-based suppression technologies, especially vegetable crops with virus resistance conferred by expression of siRNAs or miRNAs derived from viral sequences.


Assuntos
MicroRNAs/genética , Doenças das Plantas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , RNA Viral/genética , Verduras/genética , Verduras/virologia , Vírus/genética , Doenças das Plantas/virologia , Verduras/economia , Vírus/classificação , Vírus/isolamento & purificação
16.
Food Environ Virol ; 6(2): 110-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24818567

RESUMO

The preservation of water resources is one of the goals of the designation of parks that act as natural reservoirs. In order to assess the impact of the presence of humans in an environmental preservation area bordering urban areas, the presence of four pathogenic enteric viruses [group A rotavirus (RV-A), norovirus (NoV), human adenoviruses (HAdV), and hepatitis A virus (HAV)], as well as the physico-chemical parameters, and Escherichia coli levels were assessed in riverine water samples. From June 2008 to May 2009, monthly monitoring was performed along the Engenho Novo River. RV-A, NoV, and HAdV were observed in 29% (31/108) of the water samples, with concentrations of up to 10(3) genome copies/liter. The natural occurrence of infectious HAdV was demonstrated by Integrated Cell Culture-PCR (ICC-PCR). This study confirms the suitability of using the detection of fecal-oral transmitted viruses as a marker of human fecal contamination in water matrices and indicates the spread of pathogenic viruses occurring in an alleged area of environmental protection.


Assuntos
Bactérias/isolamento & purificação , Conservação dos Recursos Naturais , Rios/microbiologia , Rios/virologia , Vírus/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Brasil , Monitoramento Ambiental , Atividades Humanas , Humanos , Vírus/classificação , Vírus/genética , Poluição da Água , Qualidade da Água
17.
mBio ; 4(5): e00598-13, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-24003179

RESUMO

UNLABELLED: The majority of emerging zoonoses originate in wildlife, and many are caused by viruses. However, there are no rigorous estimates of total viral diversity (here termed "virodiversity") for any wildlife species, despite the utility of this to future surveillance and control of emerging zoonoses. In this case study, we repeatedly sampled a mammalian wildlife host known to harbor emerging zoonotic pathogens (the Indian Flying Fox, Pteropus giganteus) and used PCR with degenerate viral family-level primers to discover and analyze the occurrence patterns of 55 viruses from nine viral families. We then adapted statistical techniques used to estimate biodiversity in vertebrates and plants and estimated the total viral richness of these nine families in P. giganteus to be 58 viruses. Our analyses demonstrate proof-of-concept of a strategy for estimating viral richness and provide the first statistically supported estimate of the number of undiscovered viruses in a mammalian host. We used a simple extrapolation to estimate that there are a minimum of 320,000 mammalian viruses awaiting discovery within these nine families, assuming all species harbor a similar number of viruses, with minimal turnover between host species. We estimate the cost of discovering these viruses to be ~$6.3 billion (or ~$1.4 billion for 85% of the total diversity), which if annualized over a 10-year study time frame would represent a small fraction of the cost of many pandemic zoonoses. IMPORTANCE: Recent years have seen a dramatic increase in viral discovery efforts. However, most lack rigorous systematic design, which limits our ability to understand viral diversity and its ecological drivers and reduces their value to public health intervention. Here, we present a new framework for the discovery of novel viruses in wildlife and use it to make the first-ever estimate of the number of viruses that exist in a mammalian host. As pathogens continue to emerge from wildlife, this estimate allows us to put preliminary bounds around the potential size of the total zoonotic pool and facilitates a better understanding of where best to allocate resources for the subsequent discovery of global viral diversity.


Assuntos
Biodiversidade , Quirópteros/virologia , Vírus/classificação , Vírus/isolamento & purificação , Animais , Animais Selvagens/virologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/economia , Reação em Cadeia da Polimerase/métodos , Vírus/genética , Zoonoses/virologia
18.
Appl Environ Microbiol ; 79(18): 5450-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23793630

RESUMO

Viruses are the most abundant and diverse biological entities within soils, yet their ecological impact is largely unknown. Defining how soil viral communities change with perturbation or across environments will contribute to understanding the larger ecological significance of soil viruses. A new approach to examining the composition of soil viral communities based on random PCR amplification of polymorphic DNA (RAPD-PCR) was developed. A key methodological improvement was the use of viral metagenomic sequence data for the design of RAPD-PCR primers. This metagenomically informed approach to primer design enabled the optimization of RAPD-PCR sensitivity for examining changes in soil viral communities. Initial application of RAPD-PCR viral fingerprinting to soil viral communities demonstrated that the composition of autochthonous soil viral assemblages noticeably changed over a distance of meters along a transect of Antarctic soils and across soils subjected to different land uses. For Antarctic soils, viral assemblages segregated upslope from the edge of dry valley lakes. In the case of temperate soils at the Kellogg Biological Station, viral communities clustered according to land use treatment. In both environments, soil viral communities changed along with environmental factors known to shape the composition of bacterial host communities. Overall, this work demonstrates that RAPD-PCR fingerprinting is an inexpensive, high-throughput means for addressing first-order questions of viral community dynamics within environmental samples and thus fills a methodological gap between narrow single-gene approaches and comprehensive shotgun metagenomic sequencing for the analysis of viral community diversity.


Assuntos
Biodiversidade , Impressões Digitais de DNA/métodos , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Microbiologia do Solo , Virologia/métodos , Vírus/classificação , Vírus/isolamento & purificação , Custos e Análise de Custo , Impressões Digitais de DNA/economia , Ensaios de Triagem em Larga Escala/economia , Ensaios de Triagem em Larga Escala/métodos , Técnica de Amplificação ao Acaso de DNA Polimórfico/economia , Virologia/economia , Vírus/genética
19.
Water Res ; 47(8): 2797-810, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23535378

RESUMO

Molecular techniques and virus concentration methods have shown that previously unknown viruses are shed by humans and animals, and may be transmitted by sewage-contaminated water. In the present study, 10-L river-water samples from urban areas in Barcelona, Spain and Rio Janeiro, Brazil, have been analyzed to evaluate the viral dissemination of human viruses, validating also a low-cost concentration method for virus quantification in fresh water. Three viral groups were analyzed: (i) recently reported viruses, klassevirus (KV), asfarvirus-like virus (ASFLV), and the polyomaviruses Merkel cell (MCPyV), KI (KIPyV) and WU (WUPyV); (ii) the gastroenteritis agents noroviruses (NoV) and rotaviruses (RV); and (iii) the human fecal viral indicators in water, human adenoviruses (HAdV) and JC polyomaviruses (JCPyV). Virus detection was based on nested and quantitative PCR assays. For KV and ASFLV, nested PCR assays were developed for the present study. The method applied for virus concentration in fresh water samples is a one-step procedure based on a skimmed-milk flocculation procedure described previously for seawater. Using spiked river water samples, inter- and intra-laboratory assays showed a viral recovery rate of about 50% (20-95%) for HAdV, JCPyV, NoV and RV with a coefficient of variation ≤ 50%. HAdV and JCPyV were detected in 100% (12/12) of the river samples from Barcelona and Rio de Janeiro. Moreover, NoV GGII was detected in 83% (5/6) and MCPyV in 50% (3/6) of the samples from Barcelona, whereas none of the other viruses tested were detected. NoV GGII was detected in 33% (2/6), KV in 33% (2/6), ASFLV in 17% (1/6) and MCPyV in 50% (3/6) of the samples from Rio de Janeiro, whereas KIPyV and WUPyV were not detected. RV were only analyzed in Rio de Janeiro and resulted positive in 67% (4/6) of the samples. The procedure applied here to river water represents a useful, straightforward and cost-effective method that could be applied in routine water quality testing. The results of the assays expand our understanding of the global distribution of the viral pathogens studied here and their persistence in the environment.


Assuntos
Monitoramento Ambiental/métodos , Reação em Cadeia da Polimerase/métodos , Rios/virologia , Esgotos/virologia , Vírus/classificação , Vírus/isolamento & purificação , Brasil , Cidades , DNA/análise , Floculação , Humanos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/economia , RNA/análise , Análise de Sequência de DNA , Análise de Sequência de RNA , Espanha , Vírus/genética
20.
J Water Health ; 11(1): 110-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23428554

RESUMO

Sewage discharge is considered to be the main source of virus contamination in aquatic environments. There is no correlation between the presence of viruses and the presence of fecal coliforms in water; therefore virological markers are needed when monitoring contamination. This study investigates DNA and RNA virus concentrations in wastewater and evaluates a potential virus marker of human contamination. Influent and effluent samples were collected twice a month throughout a 1-year period. Viruses were detected using quantitative polymerase chain reaction protocols; nucleotide sequencing was carried out for virus genotyping. Human adenovirus (HAdV) and polyomavirus JC (JCPyV) were the most prevalent viruses found in influent samples (100%) with a virus load that ranged from 10(6) to 10(5) genome copies per liter (gc l(-1)). Norovirus genogroup II (NoV GII) and human astrovirus (HAstV) were less prevalent, and ranged from 10(4) to 10(3)gc l(-1). Quantitative data on virus profiles in wastewaters stress the high level of rotavirus species A environmental dissemination and address the potential of HAdV as a useful virological marker of virus contamination in aquatic environments. This study corroborates other studies performed in developed countries on DNA viruses as good markers of human fecal contamination.


Assuntos
Esgotos/virologia , Vírus/classificação , Vírus/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Microbiologia da Água/normas , Brasil , Cidades , Humanos , Dados de Sequência Molecular , Filogenia , Purificação da Água/métodos
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