RESUMEN
Noroviruses are a leading cause of acute gastroenteritis (AGE) among adults and children worldwide. NoroSurv is a global network for norovirus strain surveillance among children <5 years of age with AGE. Participants in 16 countries across 6 continents used standardized protocols for dual typing (genotype and polymerase type) and uploaded 1,325 dual-typed sequences to the NoroSurv web portal during 2016-2020. More than 50% of submitted sequences were GII.4 Sydney[P16] or GII.4 Sydney[P31] strains. Other common strains included GII.2[P16], GII.3[P12], GII.6[P7], and GI.3[P3] viruses. In total, 22 genotypes and 36 dual types, including GII.3 and GII.20 viruses with rarely reported polymerase types, were detected, reflecting high strain diversity. Surveillance data captured in NoroSurv enables the monitoring of trends in norovirus strains associated childhood AGE throughout the world on a near real-time basis.
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Infecciones por Caliciviridae , Gastroenteritis , Norovirus , Adulto , Niño , Genotipo , Humanos , Hígado , FilogeniaRESUMEN
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.
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COVID-19/diagnóstico , COVID-19/virología , Gastroenteritis/virología , ARN Viral/aislamiento & purificación , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Adulto , Brasil/epidemiología , COVID-19/epidemiología , Prueba de COVID-19 , Heces/virología , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adulto JovenRESUMEN
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.
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Diarrea Infantil/complicaciones , Infecciones por Rotavirus/epidemiología , Rotavirus/inmunología , Brasil/epidemiología , Preescolar , Clima , Diarrea Infantil/epidemiología , Diarrea Infantil/virología , Heces/virología , Femenino , Humanos , Lactante , Masculino , Filogenia , ARN Viral/análisis , Rotavirus/clasificación , Rotavirus/genética , Infecciones por Rotavirus/complicaciones , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus , Factores Socioeconómicos , Encuestas y Cuestionarios , Vacunación , Vacunas AtenuadasRESUMEN
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.
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Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus , Brasil/epidemiología , Niño , Preescolar , Genotipo , Humanos , Lactante , Estudios Retrospectivos , Rotavirus/clasificación , Rotavirus/genética , Infecciones por Rotavirus/virología , Factores de Tiempo , Cobertura de Vacunación , Vacunas AtenuadasRESUMEN
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.
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Infecciones por Caliciviridae/virología , Caliciviridae/genética , Trastornos de la Nutrición del Niño/virología , Coinfección/microbiología , Variación Genética , Estatura , Índice de Masa Corporal , Peso Corporal , Brasil/epidemiología , Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/fisiopatología , Proteínas de la Cápside/análisis , Trastornos de la Nutrición del Niño/epidemiología , Preescolar , Coinfección/epidemiología , Diarrea/virología , Escherichia coli , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/virología , Heces/virología , Femenino , Genotipo , Humanos , Lactante , Masculino , Estado Nutricional , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Shigella , Factores SocioeconómicosRESUMEN
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.
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COVID-19 , Virus , Animales , Bovinos , SARS-CoV-2/genética , COVID-19/diagnóstico , Aguas Residuales , Límite de Detección , ARN ViralRESUMEN
Rotavirus is the most common pathogen causing pediatric diarrhea and an important cause of morbidity and mortality in low- and middle-income countries. Previous evidence suggests that the introduction of rotavirus vaccines in national immunization schedules resulted in dramatic declines in disease burden but may also be changing the rotavirus genetic landscape and driving the emergence of new genotypes. We report genotype data of more than 16,000 rotavirus isolates from 40 countries participating in the Global Rotavirus Surveillance Network. Data from a convenience sample of children under five years of age hospitalized with acute watery diarrhea who tested positive for rotavirus were included. Country results were weighted by their estimated rotavirus disease burden to estimate regional genotype distributions. Globally, the most frequent genotypes identified after weighting were G1P[8] (31%), G1P[6] (8%) and G3P[8] (8%). Genotypes varied across WHO Regions and between countries that had and had not introduced rotavirus vaccine. G1P[8] was less frequent among African (36 vs 20%) and European (33 vs 8%) countries that had introduced rotavirus vaccines as compared to countries that had not introduced. Our results describe differences in the distribution of the most common rotavirus genotypes in children with diarrhea in low- and middle-income countries. G1P[8] was less frequent in countries that had introduced the rotavirus vaccine while different strains are emerging or re-emerging in different regions.
RESUMEN
Noroviruses, a major cause of acute gastroenteritis outbreaks worldwide, are constantly evolving. This ability is reflected in the speed and efficiency with which these viruses spread and remain in the human population. The present study reports the detection of a novel recombination event among norovirus genotypes in Brazil in 2008. A strain detected in a stool sample from a child with norovirus-associated gastroenteritis, residing in an African-descendant semi-closed community of Pará State, was characterized as a novel intergenotype recombinant, GII.7/GII.20, as determined by partial sequencing and SimPlot analysis.
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Población Negra , Infecciones por Caliciviridae/virología , Gastroenteritis/virología , Norovirus/clasificación , Norovirus/genética , Virus Reordenados , Secuencia de Bases , Brasil/epidemiología , Infecciones por Caliciviridae/epidemiología , Heces/virología , Gastroenteritis/epidemiología , Humanos , Lactante , Datos de Secuencia Molecular , FilogeniaRESUMEN
INTRODUCTION: Diarrhoea remains a leading cause of child morbidity and mortality. Systematically collected and analysed data on the aetiology of hospitalised diarrhoea in low-income and middle-income countries are needed to prioritise interventions. METHODS: We established the Global Pediatric Diarrhea Surveillance network, in which children under 5 years hospitalised with diarrhoea were enrolled at 33 sentinel surveillance hospitals in 28 low-income and middle-income countries. Randomly selected stool specimens were tested by quantitative PCR for 16 causes of diarrhoea. We estimated pathogen-specific attributable burdens of diarrhoeal hospitalisations and deaths. We incorporated country-level incidence to estimate the number of pathogen-specific deaths on a global scale. RESULTS: During 2017-2018, 29 502 diarrhoea hospitalisations were enrolled, of which 5465 were randomly selected and tested. Rotavirus was the leading cause of diarrhoea requiring hospitalisation (attributable fraction (AF) 33.3%; 95% CI 27.7 to 40.3), followed by Shigella (9.7%; 95% CI 7.7 to 11.6), norovirus (6.5%; 95% CI 5.4 to 7.6) and adenovirus 40/41 (5.5%; 95% CI 4.4 to 6.7). Rotavirus was the leading cause of hospitalised diarrhoea in all regions except the Americas, where the leading aetiologies were Shigella (19.2%; 95% CI 11.4 to 28.1) and norovirus (22.2%; 95% CI 17.5 to 27.9) in Central and South America, respectively. The proportion of hospitalisations attributable to rotavirus was approximately 50% lower in sites that had introduced rotavirus vaccine (AF 20.8%; 95% CI 18.0 to 24.1) compared with sites that had not (42.1%; 95% CI 33.2 to 53.4). Globally, we estimated 208 009 annual rotavirus-attributable deaths (95% CI 169 561 to 259 216), 62 853 Shigella-attributable deaths (95% CI 48 656 to 78 805), 36 922 adenovirus 40/41-attributable deaths (95% CI 28 469 to 46 672) and 35 914 norovirus-attributable deaths (95% CI 27 258 to 46 516). CONCLUSIONS: Despite the substantial impact of rotavirus vaccine introduction, rotavirus remained the leading cause of paediatric diarrhoea hospitalisations. Improving the efficacy and coverage of rotavirus vaccination and prioritising interventions against Shigella, norovirus and adenovirus could further reduce diarrhoea morbidity and mortality.
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Vacunas contra Rotavirus , Humanos , Niño , Preescolar , Incidencia , Países en Desarrollo , Diarrea/epidemiología , Diarrea/prevención & control , HospitalizaciónRESUMEN
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.
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Norovirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Brasil , Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/virología , Brotes de Enfermedades , Epidemias , Gastroenteritis/epidemiología , Gastroenteritis/virología , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Epidemiología Molecular , Norovirus/genética , Filogenia , ARN Viral , Reacción en Cadena en Tiempo Real de la Polimerasa , Aguas Residuales/virologíaRESUMEN
The widespread nature of calicivirus infections globally has a substantial impact on the health and well-being of humans and animals alike. Currently, the only vaccines approved against caliciviruses are for feline and rabbit-specific members of this group, and thus there is a growing effort towards the development of broad-spectrum antivirals for calicivirus infections. In this study, we evaluated the antiviral activity of the adenosine analogue NITD008 in vitro using three calicivirus model systems namely; feline calicivirus (FCV), murine norovirus (MNV), and the human norovirus replicon. We show that the nucleoside analogue (NA), NITD008, has limited toxicity and inhibits calicivirus replication in all three model systems with EC50 values of 0.94 µM, 0.91 µM, and 0.21 µM for MNV, FCV, and the Norwalk replicon, respectively. NITD008 has a similar level of potency to the most well-studied NA 2'-C-methylcytidine in vitro. Significantly, we also show that continual NITD008 treatment effectively cleared the Norwalk replicon from cells and treatment with 5 µM NITD008 was sufficient to completely prevent rebound. Given the potency displayed by NITD008 against several caliciviruses, we propose that this compound should be interrogated further to assess its effectiveness in vivo. In summary, we have added a potent NA to the current suite of antiviral compounds and provide a NA scaffold that could be further modified for therapeutic use against calicivirus infections.
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Adenosina/análogos & derivados , Antivirales/farmacología , Calicivirus Felino/efectos de los fármacos , Norovirus/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Adenosina/farmacología , Animales , Infecciones por Caliciviridae/tratamiento farmacológico , Infecciones por Caliciviridae/veterinaria , Infecciones por Caliciviridae/virología , Gatos/virología , Humanos , Nucleósidos/farmacologíaRESUMEN
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.
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Gastroenteritis/virología , Ríos/virología , Microbiología del Agua , Adenoviridae/genética , Adenoviridae/aislamiento & purificación , Brasil , Monitoreo del Ambiente , Heces/virología , Humanos , Mamastrovirus/genética , Mamastrovirus/aislamiento & purificación , Datos de Secuencia Molecular , Norovirus/genética , Norovirus/aislamiento & purificación , Rotavirus/genética , Rotavirus/aislamiento & purificación , Análisis de Secuencia de ADNRESUMEN
Feline calicivirus (FCV) is a major cause of upper respiratory tract disease in cats, with widespread distribution in the feline population. Recently, virulent systemic diseases caused by FCV infection has been associated with mortality rates up to 50%. Currently, there are no direct-acting antivirals approved for the treatment of FCV infection. Here, we tested 15 compounds from different antiviral classes against FCV using in vitro protein and cell culture assays. After the expression of FCV protease-polymerase protein, we established two in vitro assays to assess the inhibitory activity of compounds directly against the FCV protease or polymerase. Using this recombinant enzyme, we identified quercetagetin and PPNDS as inhibitors of FCV polymerase activity (IC50 values of 2.8 µM and 2.7 µM, respectively). We also demonstrate the inhibition of FCV protease activity by GC376 (IC50 of 18 µM). Using cell culture assays, PPNDS, quercetagetin and GC376 did not display antivirals effects, however, we identified nitazoxanide and 2'-C-methylcytidine (2CMC) as potent inhibitors of FCV replication, with EC50 values in the low micromolar range (0.6 µM and 2.5 µM, respectively). In conclusion, we established two in vitro assays that will accelerate the research for FCV antivirals and can be used for the high-throughput screening of direct-acting antivirals.
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Antivirales/farmacología , Calicivirus Felino/efectos de los fármacos , Citidina/análogos & derivados , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , Péptido Hidrolasas/metabolismo , Poliproteínas/antagonistas & inhibidores , Tiazoles/farmacología , Animales , Infecciones por Caliciviridae/tratamiento farmacológico , Infecciones por Caliciviridae/veterinaria , Infecciones por Caliciviridae/virología , Calicivirus Felino/genética , Calicivirus Felino/metabolismo , Enfermedades de los Gatos/tratamiento farmacológico , Enfermedades de los Gatos/virología , Gatos , Línea Celular , Citidina/farmacología , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/virología , Flavonas/farmacología , Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Concentración 50 Inhibidora , Nitrocompuestos , Péptido Hidrolasas/genética , Poliproteínas/genética , Poliproteínas/metabolismo , Fosfato de Piridoxal/análogos & derivados , Fosfato de Piridoxal/farmacología , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/veterinaria , Infecciones del Sistema Respiratorio/virología , Ácidos Sulfónicos/farmacologíaRESUMEN
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.
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Infecciones por Caliciviridae/epidemiología , Gastroenteritis/epidemiología , Norovirus/genética , Filogenia , ARN Viral/genética , Brasil/epidemiología , Infecciones por Caliciviridae/transmisión , Infecciones por Caliciviridae/virología , Monitoreo Epidemiológico , Heces/virología , Gastroenteritis/virología , Genotipo , Hong Kong/epidemiología , Humanos , Epidemiología Molecular , Norovirus/clasificación , Norovirus/aislamiento & purificación , PrevalenciaRESUMEN
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.
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Países en Desarrollo , Microbiología de Alimentos , Gastroenteritis/virología , Lactuca/virología , Riego Agrícola , Brasil , Infecciones por Caliciviridae/transmisión , Infecciones por Caliciviridae/virología , Heces/virología , Gastroenteritis/prevención & control , Humanos , Norovirus/genética , Norovirus/aislamiento & purificación , Salud Pública , ARN Viral/genética , Rotavirus/genética , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/transmisión , Infecciones por Rotavirus/virología , Saneamiento , Microbiología del AguaRESUMEN
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.
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Adenovirus Humanos , Aguas del Alcantarillado/virología , Eliminación de Residuos Líquidos/métodos , Floculación , HumanosRESUMEN
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.
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Infecciones por Caliciviridae/epidemiología , Diarrea/epidemiología , Gastroenteritis/epidemiología , Norovirus/aislamiento & purificación , Brasil , Preescolar , Estudios Transversales , Diarrea/virología , Heces/virología , Femenino , Gastroenteritis/virología , Genotipo , Humanos , Lactante , Masculino , Norovirus/clasificación , Norovirus/genética , Prevalencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADNRESUMEN
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.
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Infecciones por Caliciviridae/virología , Norovirus/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Infecciones por Rotavirus/virología , Rotavirus/aislamiento & purificación , Infecciones por Caliciviridae/diagnóstico , Heces/virología , Gastroenteritis/virología , Variación Genética , Genotipo , Humanos , Norovirus/genética , Filogenia , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/economía , Rotavirus/genética , Infecciones por Rotavirus/diagnóstico , Análisis de Secuencia de ADN , Carga ViralRESUMEN
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.
Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Fómites/virología , Hospitales Pediátricos , Unidades de Cuidado Intensivo Neonatal , Rotavirus/aislamiento & purificación , HumanosRESUMEN
Feline caliciviruses (FCVs) have occasionally been described in cats in association with enteric disease, but an etiological role for these viruses in acute gastroenteritis is still unclear. In this study, molecular characterization of FCV and feline norovirus (FNoV) was undertaken using real-time PCR (RT-PCR) and sequence analysis of the ORF1 region in fecal specimens from 29 diarrheic cats. The specimens were also screened for parvovirus, coronavirus, astrovirus and group A rotavirus. A quantitative one step RT-PCR was also performed to detect and quantitate NoV genogroup IV and the role of these animal caliciviruses in feline gastroenteritis was investigated. This is the first description of enteric FCV and FNoV in South America.