RESUMO
We described the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in stool samples from patients presenting only acute gastroenteritis (AGE) symptoms. From January to July 2020, 121 AGE stool samples were screened by quantitative reverse-transcription polymerase chain reaction. We detected SARS-CoV-2 in 27.5% of samples received during the epidemic period. No infectious viruses were observed in Vero E6 cells.
Assuntos
COVID-19/diagnóstico , COVID-19/virologia , Gastroenterite/virologia , RNA Viral/isolamento & purificação , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Adulto , Brasil/epidemiologia , COVID-19/epidemiologia , Teste para COVID-19 , Fezes/virologia , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Adulto JovemRESUMO
In both Brazilian and European regulations, the impact assessment of sewage discharges into coastal waters is based on microbiological analyses of fecal indicators such as Escherichia coli, frequently used in prevision hydrodynamic models. However, the decay rates of E. coli vary depending on environmental conditions, and analysis may lead to inaccurate conclusions. This study aimed to analyze the decay of culturable and viable (but not culturable) E. coli in outdoor conditions, by creating microcosms inoculated with pre-treated sewage. The microcosms were filled with 9.88 L of filtered water (0.22 µm membrane), 3.5% salt, 0.1-0.2% BHI, and 1% bacterial suspension obtained by reverse filtration. PMA-qPCR of E. coli uidA gene and Colilert measurements were applied to evaluate population counts after 2 h, 4 h, and 26 h. After nine hours of exposure to solar radiation, the viable cells decreased to 2.76% (interpolated value) of the initial population, and the cultivable fraction of the viable population accounted for 0.50%. In the dark period, the bacteria grew again, and viable cells reached 8.54%, while cultivable cells grew to 48.14% of initial population. This behavior is possibly due to the use of nutrients recycled from dead cells. Likewise, populations of E. coli in sewage outfalls remain viable in the sediments, where resuspension can renew blooming.
Assuntos
Escherichia coli , Esgotos , Brasil , Escherichia coli/genética , Fezes , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia da ÁguaRESUMO
BACKGROUND: Rotavirus A (RVA) is one of the leading causes of acute gastroenteritis worldwide; however, few studies assessed RVA genetics with community surveillance. OBJECTIVES: This study aimed to investigate clinical data, genetic diversity, and coinfection patterns of RVA infections in children from 2 to 36 months old with or without community childhood diarrhea in the Brazilian semiarid region during postvaccination era. METHODS: We enrolled and collected socioeconomic/clinical information using a standardized questionnaire and fecal samples from 291 children. Viral RNA samples were extracted and analyzed using quantitative reverse transcription polymerase chain reaction to establish the diagnosis of RVA. Sequencing of VP7 and VP4 (VP8*) regions and phylogenetic analysis were performed. RESULTS: RVA-negative diagnosis was associated with children 24 to 36 months old with complete vaccination schedule. Genotype G1P[8] was the most prevalent (57%), whereas unusual genotypes including G1P[4], G2P[8], and G3P[9] were also detected. G1- and P[8]-positive samples showed high degrees of similarity with the vaccine strain. RVA coinfections were frequently observed, and enteroaggregative Escherichia coli was the most prevalent copathogen. CONCLUSIONS: These results demonstrate that genotype G1P[8] is the most prevalent strain. VP7 and/or VP8* gene segments arising from RV1 vaccine strain were documented in these children, suggesting shedding or herd vaccination. Moreover, our study indicates full vaccination is important for protection against RVA infections.
Assuntos
Diarreia Infantil/complicações , Infecções por Rotavirus/epidemiologia , Rotavirus/imunologia , Brasil/epidemiologia , Pré-Escolar , Clima , Diarreia Infantil/epidemiologia , Diarreia Infantil/virologia , Fezes/virologia , Feminino , Humanos , Lactente , Masculino , Filogenia , RNA Viral/análise , Rotavirus/classificação , Rotavirus/genética , Infecções por Rotavirus/complicações , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus , Fatores Socioeconômicos , Inquéritos e Questionários , Vacinação , Vacinas AtenuadasRESUMO
BACKGROUND: Brazil introduced the monovalent rotavirus vaccine (Rotarix®) in 2006. This study aimed to assess the epidemiology and genotype distribution of species-A rotavirus (RVA) in Brazil, comparing the pre- and post-vaccination periods. METHODS: Laboratory-based RVA surveillance included 866 municipalities in 22 Brazilian states, over a 21-year period. A total of 16,185 children with diarrheal diseases (DD) aged up to 12 years between 1996 and 2005 (pre-vaccination period, n = 7030) and from 2006 to 2017 (post-vaccination period, n = 9155) were enrolled. RVA was detected using ELISA immune assay and/or polyacrylamide gel electrophoresis and genotyped using nested PCR and/or nucleotide sequencing. RVA-positivity and genotypes detection rates were compared in distinct periods and age groups and Rotarix vaccination status. RESULTS: RVA-positivity in pre- and post-vaccination periods was, respectively: 4-11 months bracket, 33.3% (668/2006) and 16.3% (415/2547) (p < 0.001); 12-24 months, 28.2% (607/2154) and 22.2% (680/3068) (p < 0.001); 25-48 months, 17.4% (215/1235) and 29.4% (505/1720) (p < 0.001). Genotypes distribution in the pre- and post-vaccination periods was, respectively: G1P [8]/G1P[Not Typed], 417/855 (48.8%) and 118/1835 (6.4%) (p < 0.001); G2P [4]/G2P[NT], 47/855 (5.5%) and 838/1835 (45.7%) (p < 0.001); G3P [8]/G3P[NT], 55/855 (6.4%) and 253/1835 (13.8%) (p < 0.001); G9P [8]/G9P[NT], 238/855 (27.8%) and 152/1835 (8.3%) (p < 0.001); G12P [8]/G129P[NT], 0/871 (0%) and 249/1835(13.6%) (p < 0.001). Concerning infants aged 4-11 months, RVA frequency in fully vaccinated and non-vaccinated individuals was 11.9% (125/1052) and 24.5% (58/237) (p < 0.001), respectively. In children aged 12-24 months, RVA detection rate was 18.1% (253/1395) and 29.6% (77/260) (p < 0.001), for the vaccinated and non-vaccinated individuals, respectively (p < 0.001). CONCLUSIONS: RVA infection was significantly less frequent in children aged ≤2 years with DD after implementing vaccination, mainly among vaccinated children. It was also observed a decrease of P [8] circulation and emergence of G2P[4] in 2005, and afterwards in the post-vaccine era, with spreading of G12P[8] in 2014-2015 and of G3P[8] in 2017. Continuous RVA surveillance must be carried out in this scenario.
Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus , Brasil/epidemiologia , Criança , Pré-Escolar , Genótipo , Humanos , Lactente , Estudos Retrospectivos , Rotavirus/classificação , Rotavirus/genética , Infecções por Rotavirus/virologia , Fatores de Tempo , Cobertura Vacinal , Vacinas AtenuadasRESUMO
BACKGROUND AND OBJECTIVE: Norovirus (NoV) infections are known to have high-morbidity and mortality rates and are a major health problem globally. The impact of NoV on child development is, however, poorly understood. We evaluated the distribution of NoV genotypes in children from a low-income Brazilian semiarid region, in relation with their clinical symptoms, nutritional status, and co-pathogens. METHODS: The test population included children aged 2 to 36 months from 6 cities of the Brazilian semiarid region. Fecal samples were collected from each child, along with the information regarding their socioeconomic/clinical conditions using a standardized questionnaire. Detection and quantification of NoV were performed by reverse-transcription quantitative polymerase chain reaction, followed by molecular and phylogenetic analyses. RESULTS: The NoV detection rate was 45.2%. Presence of NoV was associated with lower z scores for weight-for-age (Pâ=â0.03), weight-for-height (Pâ=â0.03), and body mass index-for-age (Pâ=â0.03). NoV infection was associated with more frequent respiratory illnesses (Pâ<â0.01). GII.P7 (polymerase) and GII.3 (capsid) were the most frequent NoV genotypes. Analysis of the open reading frame (ORF)1-2 junction identified recombinant NoV strains in 80% of the sequenced samples. Enteroaggregative Escherichia coli coinfection was the major predictor for diarrhea in NoV-positive samples (Pâ<â0.02). Moreover, Shigella spp was also associated with NoV-positive diagnosis (Pâ=â0.02). CONCLUSIONS: This study highlights the genetic variability of NoV and, associated co-infections and undernutrition in infants from low-income Brazilian semiarid region.
Assuntos
Infecções por Caliciviridae/virologia , Caliciviridae/genética , Transtornos da Nutrição Infantil/virologia , Coinfecção/microbiologia , Variação Genética , Estatura , Índice de Massa Corporal , Peso Corporal , Brasil/epidemiologia , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/fisiopatologia , Proteínas do Capsídeo/análise , Transtornos da Nutrição Infantil/epidemiologia , Pré-Escolar , Coinfecção/epidemiologia , Diarreia/virologia , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/virologia , Fezes/virologia , Feminino , Genótipo , Humanos , Lactente , Masculino , Estado Nutricional , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Shigella , Fatores SocioeconômicosRESUMO
The monitoring of environmental microbial contamination in healthcare facilities may be a valuable tool to determine pathogens transmission in those settings; however, such procedure is limited to bacterial indicators. Viruses are found commonly in those environments and are rarely used for these procedures. The aim of this study was to assess distribution and viability of a human DNA virus on fomites in an Adult Intensive Care Unit of a private hospital in Rio de Janeiro, Brazil. Human adenoviruses (HAdV) were investigated in 141 fomites by scraping the surface area and screening by quantitative PCR (qPCR) using TaqMan® System (Carlsbad, CA). Ten positive samples were selected for virus isolation in A549 and/or HEp2c cell lines. A total of 63 samples (44.7%) were positive and presented viral load ranging from 2.48 × 10(1) to 2.1 × 10(3) genomic copies per millilitre (gc/ml). The viability was demonstrated by integrated cell culture/nested-PCR in 5 out of 10 samples. Nucleotide sequencing confirmed all samples as HAdV and characterized one of them as specie B, serotype 3 (HAdV-3). The results indicate the risk of nosocomial transmission via contaminated fomites and point out the use of HAdV as biomarkers of environmental contamination.
Assuntos
Adenovírus Humanos/isolamento & purificação , Adenovírus Humanos/fisiologia , Fômites/virologia , Hospitais , Viabilidade Microbiana , Adulto , Brasil , Linhagem Celular , Células Epiteliais/virologia , Genótipo , Hepatócitos/virologia , Humanos , Unidades de Terapia Intensiva , Reação em Cadeia da Polimerase em Tempo Real , Sorogrupo , Carga Viral , Cultura de VírusRESUMO
Wastewater-based epidemiology has been described as a valuable tool for monitoring the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a community. However, there is no consensus on the best concentration method to allow reliable detection of SARS-CoV-2 in this matrix, considering different laboratory facilities. This study compares two viral concentration methods, ultracentrifugation (ULT) and skimmed-milk flocculation (SMF), for detecting SARS-CoV-2 in wastewater samples. The analytical sensitivity (limits of detection and quantification [LoD/LoQ]) of both methods was evaluated using a bovine respiratory syncytial virus (BRSV) as a surrogate. Three different approaches were conducted to establish LoD of each method based on the assays on the standard curve (ALoDsc), on the dilution of internal control (ALoDiC), and the processing steps (PLoD). For PLoD, ULT method had the lowest value (1.86 × 103 genome copy/microliter [GC/µL]) when compared to the SMF method (1.26 × 107 GC/µL). The LoQ determination showed a mean value of 1.55 × 105 GC/µL and 3.56 × 108 GC/µL to ULT and SMF, respectively. The detection of SARSCoV-2 in naturally contaminated wastewater revealed 100% (12/12) and 25% (3/12) of detection using ULT and SMF with quantification ranging from 5.2 to 7.2 log10 genome copy/liter (GC/L) and 5.06 to 5.46 log10 GC/L, respectively. The detection success rate of BRSV used as an internal control process was 100% (12/12) for ULT and 67% (8/12) for SMF, with an efficiency recovery rate ranging from 12 to 38% and 0.1 to 5%, respectively. Our data consolidates the importance of assessing the methods used; however, further analysis should be carried out to improve low-cost concentration methodologies, essential for use in low-income and developing countries.
Assuntos
COVID-19 , Vírus , Animais , Bovinos , SARS-CoV-2/genética , COVID-19/diagnóstico , Águas Residuárias , Limite de Detecção , RNA ViralRESUMO
The effective food processing technology is a key step in eliminating human noroviruses in foods mainly due to their stability in diverse environmental conditions. The aim of this study was to evaluate the effect of rising temperatures for inactivation of norovirus genogroup (G) II and murine norovirus 1 in samples of tomato sauce (72-74 °C for 1 min) and ground meat (100 °C for 30 min). Spiking experiments were carried out in triplicate using TRIzol® reagent method associated with quantitative polymerase chain reaction (qPCR) TaqMan™ system combined with previous free RNA digestion. Success rate and efficiency recoveries of both viruses as well limit of detection of a method for each matrix were also conducted. The heat treatment applied here proved to be efficient to reduce the burden of norovirus GII in a range of 1-4 log10 genomic copies per gram (percentage ranging from 0.45 to 104.54%) in both matrices. The experiments in this study showed that the results of norovirus GII and murine norovirus 1 in tomato sauce and ground meat tested during thermal treatments cannot be generalized to other food matrices, since there may be food-specific protective effects, as the presence of different components, that can interfere in virus inactivation. Studies using different food matrices reinforce the importance to investigate viruses' inactivation thermal processes in foods due to the resistance of these viruses to adverse conditions, contributing to food security in food virology.
Assuntos
Norovirus , Animais , Manipulação de Alimentos , Genótipo , Temperatura Alta , Humanos , Carne , Camundongos , Norovirus/genética , Inativação de VírusRESUMO
Rotaviruses are important enteric pathogens for humans and animals. Group A rotaviruses (RV-A) are the most common agents of severe gastroenteritis in infants and young children and vaccination is the most effective method to reduce RV-A-associated diseases. G1P[8], the most prevalent RV-A genotype worldwide, is included in the RV-A vaccine Rotarix®. The discrimination between wild-type G1P[8] and vaccine G1P[8] strains is an important topic in the study of RV-A epidemiology to manage outbreaks and to define control measures for vaccinated children. In this study, we developed a novel method to segregate the wild-type and vaccine strains using restriction endonucleases. The dsRNA from the Rotarix® vaccine was sequenced and the NSP3 gene was selected as the target gene. The vaccine strain has a restriction pattern that is different than that of wild-type RV-A G1P[8] isolates after digestion with the restriction endonuclease BspHI. This pattern could be used as a marker for the differentiation of wild-type G1P[8] strains from the vaccine strain.
Assuntos
Fezes/virologia , Vacinas contra Rotavirus/genética , Rotavirus/genética , Enzimas de Restrição do DNA/genética , Genótipo , Humanos , Polimorfismo de Fragmento de Restrição , Rotavirus/isolamento & purificação , Infecções por Rotavirus/virologia , Vacinas Atenuadas/genéticaRESUMO
Three drinking-water treatment plants were analyzed for the presence of human adenoviruses (HAdV) and JC polyomavirus (JCPyV), previously suggested as viral contamination indicators, in order to define their water quality in relation to the presence of viral pathogens and the efficiency of the treatments applied. The 90% of the river water samples had positive results of HAdV (10(1)-10(4) genome copies (GC)/L); and 48%, of JCPyV (10(0)-10(3)GC/L). Lower concentrations of HAdV and JCPyV were found in different treatment steps of the plants in absence of bacterial standards. Virus removal efficiencies were higher than 5 logs in plants 1 and 3 and could be quantified as >2 logs in plant 2. However, three post-chlorinated samples from plants 2 and 3 (11%) were found to be positive for HAdV by qPCR, but did not show infectivity in the cell cultures assayed. Simple methods based on the adsorption-elution of viruses from glass wool give low-cost and efficient virus recovery from source water and large-volume water samples. Quantification of JCPyV and HAdV using qPCR is useful for evaluating virus removal efficiency in water treatment plants, identification of Hazard Analysis and Critical Control Points (HACCP) and as a molecular index of the virological quality of water. Though infectivity is not guaranteed when using qPCR techniques in water treated with disinfection processes, the quality of source water, where viruses have proved to have infective capabilities, and the removal efficiency of viral particles may be efficiently quantified.
Assuntos
Adenoviridae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Polyomavirus/isolamento & purificação , Microbiologia da Água , Adenoviridae/genética , Polyomavirus/genética , Abastecimento de ÁguaRESUMO
This study aimed to survey the environmental dissemination of enterovirus (EV) in a site of organic lettuce situated in the mountainous region of the state of Rio de Janeiro, Brazil. For this purpose, a total of 96 environmental samples, including water and lettuce samples obtained in different stages of the production chain (e.g., irrigation water, seedlings, lettuces grown, and washed lettuces ready-to-eat), were analyzed. EV genomes were detected in 12.5% (12/96) of the tested samples (eight from irrigation water and 4 from lettuce samples). Levels of viral concentration ranged from 3.37 × 103 to 4.72 × 106 genomic copies per liter (gc L-1 ) and from 2.14 × 104 to 5.56 × 104 genome copies per 25 grams (gc 25 g-1 ) for the water and lettuce samples, respectively. Such findings suggest that the use of viruses as human fecal contamination markers must be considered in order to improve food safety in organic supply chains.
Assuntos
Enterovirus/isolamento & purificação , Microbiologia Ambiental , Contaminação de Alimentos , Microbiologia de Alimentos , Lactuca/virologia , Brasil , Humanos , Carga ViralRESUMO
Noroviruses are a leading cause of epidemic and pandemic acute gastroenteritis (AGE) worldwide, and contaminated food and water are important routes for its transmission. Raw sewage has been used for viral surveillance to monitor the emergence of new norovirus strains with the potential to cause epidemics. In this study, we investigated norovirus occurrence and norovirus RNA levels in 156 samples collected from May 2013 to May 2014, across three different stages (52 samples each) of a wastewater treatment plant (WWTP) in Rio de Janeiro, Brazil. We also explored norovirus GII diversity in raw sewage samples by next-sequencing generation (NGS). In addition, we examined norovirus prevalence and molecular epidemiology from acute gastroenteritis cases. Using RT-qPCR, norovirus GI and GII was detected in 38.5% and 96.1% of raw sewage samples, 40.4% and 96.1% of primary effluent samples and 1.9% and 5.8% of final effluent samples, respectively. Norovirus RNA levels varied from 4 to 6.2 log10 genome copies per litre (gc L-1) for GI and from 4.4 to 7.3â¯log10â¯gcâ¯L-1 for GII. Using MiSeq NGS, we identified 13 norovirus genotypes over the one-year period, with six dominant capsid genotypes, including GII.4, GII.17, GII.5, GII.2, GII.3 and GII.1. GII.4 noroviruses were the most prevalent in wastewater samples (68.5%), and a similar trend was observed in AGE cases (71%). The emergent GII.17 was the second most prevalent genotype (14.3%) identified in the raw sewage samples, however, it was not detected in clinical cases. Due to the high burden of norovirus outbreaks and the lack of vaccine and antiviral drugs, it is essential to understand the genotypic diversity of norovirus at the population level. Complementary data obtained from both clinical and environmental (sewage) samples proved to be an effective strategy to monitor the circulation and emergence of norovirus epidemic genotypes.
Assuntos
Norovirus/isolamento & purificação , Esgotos/virologia , Brasil , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Surtos de Doenças , Epidemias , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Epidemiologia Molecular , Norovirus/genética , Filogenia , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , Águas Residuárias/virologiaRESUMO
To assess the presence of the four main viruses responsible for human acute gastroenteritis in a hydrographic network impacted by a disordered urbanization process, a 1-year study was performed involving water sample collection from streams in the hydrographic basin surrounding the city of Manaus, Amazonas, Brazil. Thirteen surface water sample collection sites, including different areas of human settlement characterized as urban, rural, and primary forest, located in the Tarumã-Açu, São Raimundo, Educandos, and Puraquequara microbasins, were defined with a global positioning system. At least one virus was detected in 59.6% (31/52) of the water samples analyzed, and rotavirus was the most frequent (44.2%), followed by human adenovirus (30.8%), human astrovirus (15.4%), and norovirus (5.8%). The viral contamination observed mainly in the urban streams reflected the presence of a local high-density population and indicated the gastroenteritis burden from pathogenic viruses in the water, principally due to recreational activities such as bathing. The presence of viral genomes in areas where fecal contamination was not demonstrated by bacterial indicators suggests prolonged virus persistence in aquatic environments and emphasizes the enteric virus group as the most reliable for environmental monitoring.
Assuntos
Gastroenterite/virologia , Rios/virologia , Microbiologia da Água , Adenoviridae/genética , Adenoviridae/isolamento & purificação , Brasil , Monitoramento Ambiental , Fezes/virologia , Humanos , Mamastrovirus/genética , Mamastrovirus/isolamento & purificação , Dados de Sequência Molecular , Norovirus/genética , Norovirus/isolamento & purificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Análise de Sequência de DNARESUMO
A newly GII.17 Kawazaki_2014 variant strain was detected recently in Brazil. Phylogenetic analysis reveals at least four independent introduction events of this lineage into this country that took place throughout 2014, coinciding with FIFA World Cup in Brazil, 2014, and Hong Kong has been identified as the most likely source of introduction. This variant emerged in Asia causing outbreaks and replacing prevalent GII.4. Emergence of GII.P17/GII.17 variant emphasizes the need for active laboratory surveillance for NoV including molecular epidemiology and studies on virus evolution.
Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Norovirus/genética , Filogenia , RNA Viral/genética , Brasil/epidemiologia , Infecções por Caliciviridae/transmissão , Infecções por Caliciviridae/virologia , Monitoramento Epidemiológico , Fezes/virologia , Gastroenterite/virologia , Genótipo , Hong Kong/epidemiologia , Humanos , Epidemiologia Molecular , Norovirus/classificação , Norovirus/isolamento & purificação , PrevalênciaRESUMO
Investigation of major viruses responsible for acute viral gastroenteritis, such as norovirus (NoV), rotavirus species A (RVA) and human adenovirus (HAdV), was conducted in the mountainous region of the state of Rio de Janeiro in a lettuce-producing area. Irrigation water and lettuce samples were collected at different production stages. Viruses were concentrated using an adsorption-elution method and detected by quantitative polymerase chain reaction (qPCR). We detected HAdV in all collection points, although no virus infectivity was shown. The RVA was the most prevalent virus from both water (16.7% [10/60]) and lettuce samples (11.1% [4/36]), with loads ranging from 2.97 × 102 to 6.88 × 103 genomic copies per litre (gc L-1) and 6.24 × 102 to 1.30 × 104 gc per 25 g, respectively. NoV was detected in 8.33% [8/96] in water and lettuce samples, with concentrations ranging from 7.29 × 101 to 1.92 × 103 gc L-1 and from 4.29 × 101 to 2.98 × 103 gc 25 g-1, respectively. Escherichia coli values also demonstrated poor quality of the irrigation and washing water. The presence of at least two different virus strains in all sites reveals the need to improve basic sanitation measures in order to increase food safety.
Assuntos
Países em Desenvolvimento , Microbiologia de Alimentos , Gastroenterite/virologia , Lactuca/virologia , Irrigação Agrícola , Brasil , Infecções por Caliciviridae/transmissão , Infecções por Caliciviridae/virologia , Fezes/virologia , Gastroenterite/prevenção & controle , Humanos , Norovirus/genética , Norovirus/isolamento & purificação , Saúde Pública , RNA Viral/genética , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/transmissão , Infecções por Rotavirus/virologia , Saneamento , Microbiologia da ÁguaRESUMO
Return of treated sludge to the environment poses concerns and has stimulated the development of studies on viral monitoring in this matrix, in order to assess its potential risks for public health. Human adenovirus (HAdV) has been identified as a putative viral marker of faecal contamination due to its stability and resistance to the sewage treatment process. The aim of this study was to optimize the organic flocculation procedure in order to establish an appropriate methodology for HAdV recovery from sewage sludge samples. Four protocols (A-D) have been proposed, with changes in the initial sample dilution, in the stirring time and in the final concentration of skimmed-milk. A single sludge sample was obtained in Wastewater Treatment Plant (WWTP) and divided into aliquots. In each protocol, three aliquots were inoculated with HAdV and bacteriophage PP7 and a non-inoculated one was used as negative control. Viral load and recovery rate were determined by quantitative PCR. HAdV recovery rate varied between the protocols tested (p=0.016) and the best result was obtained through the protocol C. In order to confirm this result a field study with activated, thickened and digested sludge samples was carried out. Different types of sludge were obtained in two WWTPs and processed using protocol C. HAdV was detected in all samples, with a similar or higher viral load than those obtained with other concentration techniques already applied to sludge. Protocol C proved to be really efficient, with the advantage of showing low cost and practicability in routine laboratories.
Assuntos
Adenovírus Humanos , Esgotos/virologia , Eliminação de Resíduos Líquidos/métodos , Floculação , HumanosRESUMO
BACKGROUND: Gastroenteritis is one of the most important causes of morbidity and mortality in children and an important etiological agent is norovirus. OBJECTIVE: We describe the occurrence and characteristics of norovirus diarrhoea in children from Sergipe, Northeast-Brazil, over two consecutive periods of three years following rotavirus vaccine introduction. STUDY DESIGN: A cross sectional hospital-based survey conducted from October-2006 to September-2009 and from July-2011 to January-2013. Acute diarrhoea cases had a stool sample collected and tested for norovirus by RT-PCR and positive samples were sequenced. RESULTS: In total 280 (19.6%) of 1432 samples were norovirus positive, including 204 (18.3%) of 1113 samples collected during the first period and 76 (23.9%) of 318 collected during the second period. The proportion of children with norovirus infection increased significantly through the second study period (χ2 for trend=6.7; p=0.009), was more frequent in rotavirus vaccinated and in younger children (p<0.001). Of 280 norovirus-positive specimens, 188 (67.1%) were sequenced. Of these, 12 were genogroup I and 176 genogroup II. The main genotype was GII.4 (149/188, 79.3%), followed by GII.2 (6, 3.2%) and GII.6 (5, 2.6%). CONCLUSION: Norovirus annual detection rates increased over the study period. The detection of norovirus was higher among young children.
Assuntos
Infecções por Caliciviridae/epidemiologia , Diarreia/epidemiologia , Gastroenterite/epidemiologia , Norovirus/isolamento & purificação , Brasil , Pré-Escolar , Estudos Transversais , Diarreia/virologia , Fezes/virologia , Feminino , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Masculino , Norovirus/classificação , Norovirus/genética , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNARESUMO
OBJECTIVE: To study the etiology of exanthema cases, with or without fever, in children seen in the emergency room of a hospital located in a region where dengue is endemic. METHODS: Enrollment took place between 21/09/2001 and 20/09/2002 and included 95.9% (71/74) of children presenting with exanthema at the emergency room of the Hospital Universitário de Campo Grande, MS (4.1% refusals). After the children had had their details taken and entered on the study protocol, they were subjected to physical examination followed by collection of blood samples for blood testing with platelet counts and serology (IgM and IgG); initially for dengue, rubella and toxoplasmosis and then, in negative cases, serology was also run for parvovirus, herpes virus type 6 and measles. RESULTS: Laboratory diagnoses were confirmed by means of IgM antibody assay in 88.7% of the cases investigated: dengue (77.5%), herpes virus type 6 (8.4%), parvovirus (2.8%) and in eight patients diagnosis was inconclusive (11.3%). On this occasion no positive serology (IgM) was observed for measles, rubella or toxoplasmosis. The most common clinical manifestations among the dengue patients were: fever, itching, prostration, myalgia and positive tourniquet test results. In 58.4% (32/55) of those cases diagnosed with dengue, the tourniquet test was positive, which was a statistically significant difference when compared with the remainder of the sample. CONCLUSIONS: When children present with exanthema, it is possible that dengue is the primary causative disease, depending on the epidemiology of the location. Constant control of epidemiological and serological surveillance of exanthematous diseases is necessary.
Assuntos
Dengue/complicações , Doenças Endêmicas , Exantema/virologia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Dengue/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Soroepidemiológicos , Distribuição por Sexo , TorniquetesRESUMO
Rotavirus A (RVA) and noroviruses (NoV) are the major viral agents of acute gastroenteritis (AGE) worldwide. In the present study, we aimed to evaluate the performance of a one-step duplex quantitative RT-PCR (dRT-qPCR) assay, established for detection and quantification of RVA and NoV genogroup II (GII) using a single DNA standard curve (SC), as well as to investigate the association between fecal viral load and optical density (OD) values, and viruses' genotyping. The results obtained by dRT-qPCR in 530 fecal samples from AGE cases were compared with methods employed for the diagnosis of those viruses as follows: enzyme immunoassay (EIA) and polyacrylamide gel electrophoresis (PAGE) for RVA; and qualitative PCR for NoV. By using dRT-qPCR, we detected RVA and NoV in 353 (66%), increasing the positivity rate by 22.5% for RVA and 11.5% NoV, comparing the number of positive samples. RVA and NoV GII were detected in a range of 5.17 × 10(3) to 6.56 × 10(9) and 3.76 × 10(3) to 9.13 × 10(10) genome copies per gram of feces, respectively. We observed a significant direct correlation between genome copies values and optical density, using dRT-qPCR and EIA assays, respectively (Spearman ρ=0.41; p<0.0001). Viruses characterization demonstrated a predominance of NoV GII.4 Sidney 2012 variant during October 2013 to February 2014, followed by the emergence of RVA genotype G12P[8] in 2014. The established assay using a single SC provides an early feedback concerning detection and quantification, with the advantage of detecting simultaneously RVA and NoV GII, reducing time and reagent costs.
Assuntos
Infecções por Caliciviridae/virologia , Norovirus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções por Rotavirus/virologia , Rotavirus/isolamento & purificação , Infecções por Caliciviridae/diagnóstico , Fezes/virologia , Gastroenterite/virologia , Variação Genética , Genótipo , Humanos , Norovirus/genética , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/economia , Rotavirus/genética , Infecções por Rotavirus/diagnóstico , Análise de Sequência de DNA , Carga ViralRESUMO
Rotavirus A and human adenovirus dissemination were demonstrated both in a pediatric ward and in a neonatal intensive care unit (NICU) of the same pediatric hospital. Virus detection from fomites samples were higher in the pediatric ward (42.3% [137 out of 324]) than in the NICU (4.5% [7 out of 156]), revealing that cleaning processes used in our NICU are effective in reducing viral contamination, suggesting human adenovirus as a potential biomarker of contamination of hospital fomites.