No description available.

Genome-scale ordered RNA structure (GORS) was first identified in 2004. It refers to the presence of secondary structure throughout the length of the RNA genomes of certain genera of RNA virus families, as predicted by bioinformatic analysis. It was also observed that the viruses containing GORS were able to establish persistent infections in their natural hosts, raising the possibility that the presence of GORS could play a role in viral avoidance of the innate immune system. This thesis describes the first study of GORS and its possible role in persistence. Two GORS viruses have been studied, equine rhinitis A virus (ERAV) and murine norovirus (MNV). A 55% seroprevalence of ERAV has been determined in a cohort of Scottish horses indicating a wide exposure to the virus. Equine faecal samples were screened for ERAV by PCR with the intention of identifying a virus, possibly from a persistently infected animal, which would not have undergone any cell culture adaptations as laboratory strains have. Newly identified viruses would then be sequenced, their secondary structures predicted and further studies carried out. Unfortunately, none of the 50 faecal samples screened were positive and clinical isolates of ERAV provided by the Animal Health Trust were sequenced but were identical to laboratory strains, so the study then focussed on MNV. Prevalence of MNV in laboratory mice was determined by PCR of faecal samples to be 67%. MNV was also discovered in the faeces of a pet shop mouse and a wild wood mouse (Apodemus sylvaticus). The complete genomes of 4 laboratory mouse MNVs, the pet shop mouse and wood mouse MNVs were sequenced. Phylogenetic analysis showed the wood mouse MNV had a p distance of 23% from other MNVs, although the laboratory mice and pet shop mouse were closely related to other MNVs. Structural analysis of the genomes of 6 sequenced MNVs, including the wood mouse virus, showed all were GORS viruses. A laboratory strain of MNV, MNV-3, was serially passaged in RAW 264.7 cells to test the hypothesis that in an animal with an intact immune system, there is a pressure for GORS viruses to maintain their genomic RNA structure as a means of immune avoidance, and that cell culture adaptation would attenuate the degree of secondary structure. The complete genome of passage 33 was sequenced, which revealed 7 base mutations, a mutation rate of 0.1 %, which was not considered significant enough to have affected the degree of secondary structure. In order to assess if structured and unstructured RNA behaved differently in cells, replication deficient RNA transcripts were made from the infectious clones of a panel of GORS and non-GORS viruses. These transcripts were electroporated into cells and their rate of decay measured, but there was no difference between the GORS and non-GORS transcripts. The full length and 4 kilobase transcripts were transfected into NIH3T3 cells and the degree of interferon-β induction measured by quantitative PCR and a luciferase reporter assay. The IFN-β response differed across the panel of viruses, and although none of the GORS viruses induced strongly, the non-GORS viruses were variable in their ability to induce an IFN-β response, some inducing strongly, other not at all. This result indicates that during exposure of viral genomes in the cytoplasm during infection, GORS-virus RNAs are unlikely to induce an interferon response, possibly contributing to their ability to persist. It is unclear why some non-GORS-viruses failed to induce IFN and there are likely to be other contributory factors.

Norovirus is the commonest cause of viral gastroenteritis, affecting all age groups worldwide. Outbreaks frequently occur in semi-closed communities such as schools, cruise ships, prisons and hospitals. Within the healthcare environment, the economic and logistical burdens and the inconvenience caused by norovirus is significant, since ward closure remains central to infection control. The aim of this study was to investigate norovirus transmission dynamics during hospital outbreaks. The ultimate goal was to provide information that could, in future, lead to the development of novel, less disruptive approaches to curtailing the spread of infection. The study explored the application of 'next generation' high throughput DNA sequencing technologies to the determination of large numbers of norovirus genomes. Whole genome sequences provide the highest possible level of discrimination among viruses, information which is essential to the identification of linked and independent cases of infection. The approach exploits the high norovirus mutation rate, which is typical of RNA viruses. Consequently, viruses within a single ward which differ by more than a few SNVs can be considered to represent independent introductions, rather than a single outbreak. Whole genome sequence data (determined for noroviruses collected between 2009 and 2013) were combined with epidemiological data, providing further insights into transmission dynamics. These data identified multiple independent virus introductions during single ward outbreaks. The possible origin of such outbreaks in Oxfordshire hospitals were investigated using viruses originating in the local community, and in other healthcare environments distributed throughout the UK. Whole genome sequences of noroviruses from consecutive years were genetically divergent, confirming the rapid evolution of the virus over time and excluding the possibility of prolonged environmental contamination as a reservoir of infection. Such detailed information on norovirus transmission within the healthcare environment could inform alternative future approaches to optimising infection control within the healthcare setting.

Introdução: Norovírus é o principal agente viral de infecções gastrointestinais no mundo e sua alta infectividade gera aumento importante da demanda e dos custos para a saúde pública. Surtos ocorrem em ambientes fechados ou com aglomeração de pessoas. No município de São Paulo, o Norovírus tem se destacado como principal agente etiológico das gastroenterites. Objetivo: Descrever as noroviroses como causa de gastroenterite epidêmica no Município de São Paulo no período de 2010 a 2016. Métodos: Estudo transversal descritivo com dados dos sistemas de Vigilância Epidemiológica de surtos de gastroenterite e da Vigilância Sentinela Laboratorial do Rotavírus do Município de São Paulo entre os anos de 2010 a 2016. A definição de caso foi a identificação laboratorial do Norovírus como agente etiológico de surto de doença diarreica em todas as faixas etárias ou de casos esporádicos em menores de cinco anos internados em unidades sentinelas da Vigilância do Rotavírus. Os dados foram descritos segundo tempo, lugar e pessoa, por meio do Epi InfoTM versão 3.5.4 e ArcGIS versão 10.1. Resultados: O Norovírus foi associado a 20,4 por cento (68/334) dos surtos com pesquisa de agente realizada. Ocorrendo com maior frequência na região Norte, seguida das regiões Sul e Sudeste do Município de SP; principalmente em creches, domicílios e hospitais. Houve um predomínio de casos em crianças menores de 5 anos (47,2 por cento do sexo masculino; 28,6 por cento do sexo feminino) e em mulheres entre 20 a 49 anos (38,9 por cento). Na Vigilância Sentinela Laboratorial do Rotavírus do município de São Paulo, o Norovírus foi associado a 28,4 por cento (444/1565) dos casos menores de 5 anos. Os casos foram provenientes principalmente das regiões Norte e Sul, onde estão localizadas as duas unidades sentinelas. Verificou-se pico de ocorrência do Norovírus nos meses mais quentes. Destaca-se que o perfil das gastroenterites descrito foi fortemente influenciado pelas características da Vigilância Epidemiológica das Doenças de Transmissão Alimentar do Município de São Paulo. Conclusão: O Norovírus foi o principal agente etiológico de surtos de gastroenterite e de casos menores de 5 anos internados por diarreia aguda no Município de São Paulo. A vigilância das gastroenterites por Norovírus é importante para o estabelecimento de uma rede integrada entre diferentes estados e países que possibilitem o conhecimento da doença, planejamento de medidas de prevenção e controle e comunicação da informação. / Introduction: Norovirus is the major viral agent of gastroenteritis in the world and its high infectivity causes an important increase in demand and costs for public health. Outbreaks occur in closed environments or crowded settings. In the city of São Paulo, Norovirus has been highlighted as the main etiological agent of gastroenteritis. Objective: To describe the noroviruses as the cause of epidemic gastroenteritis in the city of São Paulo from 2010 to 2016. Methods: Descriptive cross-sectional study with data from the Epidemiological Surveillance systems of gastroenteritis outbreaks and Laboratory Sentinel Surveillance of Rotavirus of the city of São Paulo from 2010 and 2016. The case definition was the laboratory identification of Norovirus as the etiological agent of diarrheal disease outbreak in all age groups or sporadic cases in children under five years of age hospitalized in sentinel units of Rotavirus Surveillance. The data were described by time, place and person, using Epi InfoTM version 3.5.4 and ArcGIS version 10.1. Results: Norovirus was associated to 20.4 per cent (68/334) of outbreaks with agent identification performed. Occurred more frequently in the North region, followed by the South and Southeast regions of the city of São Paulo, especially in nurseries, residences and hospitals. A predominance of cases in children aged <5 years (47.2 per cent male, 28.6 per cent female) and in women aged 20 to 49 years (38.9 per cent) was observed. In the Laboratory Sentinel Surveillance of Rotavirus in the city of São Paulo, Norovirus was associated with 28.4 per cent (444/1565) of cases in children younger than 5 years old. The cases were mainly from the North and South regions, where the two sentinel units are placed. There was a peak of Norovirus occurrence in warmer months. It can be noticed that the profile of gastroenteritis described was strongly influenced by the characteristics of Foodborne Disease Surveillance of the city of São Paulo. Conclusion: Norovirus was the major etiological agent of gastroenteritis outbreaks and diarrhea cases under 5 years old hospitalized in the city of São Paulo. Surveillance of gastroenteritis caused by Norovirus is important for the establishment of an integrated network between different states and countries to contribute to disease knowledge, planning of prevention and control actions and distribution of information.

Introdução: Norovírus é o principal agente viral de infecções gastrointestinais no mundo e sua alta infectividade gera aumento importante da demanda e dos custos para a saúde pública. Surtos ocorrem em ambientes fechados ou com aglomeração de pessoas. No município de São Paulo, o Norovírus tem se destacado como principal agente etiológico das gastroenterites. Objetivo: Descrever as noroviroses como causa de gastroenterite epidêmica no Município de São Paulo no período de 2010 a 2016. Métodos: Estudo transversal descritivo com dados dos sistemas de Vigilância Epidemiológica de surtos de gastroenterite e da Vigilância Sentinela Laboratorial do Rotavírus do Município de São Paulo entre os anos de 2010 a 2016. A definição de caso foi a identificação laboratorial do Norovírus como agente etiológico de surto de doença diarreica em todas as faixas etárias ou de casos esporádicos em menores de cinco anos internados em unidades sentinelas da Vigilância do Rotavírus. Os dados foram descritos segundo tempo, lugar e pessoa, por meio do Epi InfoTM versão 3.5.4 e ArcGIS versão 10.1. Resultados: O Norovírus foi associado a 20,4 por cento (68/334) dos surtos com pesquisa de agente realizada. Ocorrendo com maior frequência na região Norte, seguida das regiões Sul e Sudeste do Município de SP; principalmente em creches, domicílios e hospitais. Houve um predomínio de casos em crianças menores de 5 anos (47,2 por cento do sexo masculino; 28,6 por cento do sexo feminino) e em mulheres entre 20 a 49 anos (38,9 por cento). Na Vigilância Sentinela Laboratorial do Rotavírus do município de São Paulo, o Norovírus foi associado a 28,4 por cento (444/1565) dos casos menores de 5 anos. Os casos foram provenientes principalmente das regiões Norte e Sul, onde estão localizadas as duas unidades sentinelas. Verificou-se pico de ocorrência do Norovírus nos meses mais quentes. Destaca-se que o perfil das gastroenterites descrito foi fortemente influenciado pelas características da Vigilância Epidemiológica das Doenças de Transmissão Alimentar do Município de São Paulo. Conclusão: O Norovírus foi o principal agente etiológico de surtos de gastroenterite e de casos menores de 5 anos internados por diarreia aguda no Município de São Paulo. A vigilância das gastroenterites por Norovírus é importante para o estabelecimento de uma rede integrada entre diferentes estados e países que possibilitem o conhecimento da doença, planejamento de medidas de prevenção e controle e comunicação da informação. / Introduction: Norovirus is the major viral agent of gastroenteritis in the world and its high infectivity causes an important increase in demand and costs for public health. Outbreaks occur in closed environments or crowded settings. In the city of São Paulo, Norovirus has been highlighted as the main etiological agent of gastroenteritis. Objective: To describe the noroviruses as the cause of epidemic gastroenteritis in the city of São Paulo from 2010 to 2016. Methods: Descriptive cross-sectional study with data from the Epidemiological Surveillance systems of gastroenteritis outbreaks and Laboratory Sentinel Surveillance of Rotavirus of the city of São Paulo from 2010 and 2016. The case definition was the laboratory identification of Norovirus as the etiological agent of diarrheal disease outbreak in all age groups or sporadic cases in children under five years of age hospitalized in sentinel units of Rotavirus Surveillance. The data were described by time, place and person, using Epi InfoTM version 3.5.4 and ArcGIS version 10.1. Results: Norovirus was associated to 20.4 per cent (68/334) of outbreaks with agent identification performed. Occurred more frequently in the North region, followed by the South and Southeast regions of the city of São Paulo, especially in nurseries, residences and hospitals. A predominance of cases in children aged <5 years (47.2 per cent male, 28.6 per cent female) and in women aged 20 to 49 years (38.9 per cent) was observed. In the Laboratory Sentinel Surveillance of Rotavirus in the city of São Paulo, Norovirus was associated with 28.4 per cent (444/1565) of cases in children younger than 5 years old. The cases were mainly from the North and South regions, where the two sentinel units are placed. There was a peak of Norovirus occurrence in warmer months. It can be noticed that the profile of gastroenteritis described was strongly influenced by the characteristics of Foodborne Disease Surveillance of the city of São Paulo. Conclusion: Norovirus was the major etiological agent of gastroenteritis outbreaks and diarrhea cases under 5 years old hospitalized in the city of São Paulo. Surveillance of gastroenteritis caused by Norovirus is important for the establishment of an integrated network between different states and countries to contribute to disease knowledge, planning of prevention and control actions and distribution of information.

As bactérias patogênicas em moluscos bivalves podem ser agentes causadores de doenças como a gastroenterite e responsáveis por vários surtos de origem alimentar, representado um risco para os consumidores. Os vírus entéricos são a causa mais comum de surtos de gastroenterites não bacteriana em humanos no mundo e podem ser encontrados nas águas utilizadas no cultivo de moluscos bivalves. Este estudo teve como objetivo avaliar a contaminação de mexilhões (Mytella falcata) e ostras (Crassostrea brasiliana) provenientes do Complexo Estuarino Lagunar de Cananéia-Iguape, Estado de São Paulo, por bactérias (coliformes totais, coliformes termotolerantes, patotipos de Escherichia coli), por astrovírus e norovírus humanos. Um total de 150 amostras de moluscos bivalves (75 ostras e 75 mexilhões) foram coletadas de junho de 2016 a fevereiro de 2017. A estimativa de coliformes totais nos tecidos das ostras variou de 14,1 a 154,5 número mais provável (NMP)/g e de coliformes termotolerantes de 3,0 a 48,6 NMP/g, enquanto que para as amostras de mexilhões, os coliformes totais variaram de 97,4 a 1300 NMP/g e coliformes termotolerantes de 3,6 a 927 NMP/g. E. coli foi detectada em 24 amostras (16%), em concentrações variando entre &lt;3 e &gt;927 NMP/g. Quatro amostras (17%) foram identificadas com Escherichia coli enteropatogênica (EPEC), apresentando o gene eae por PCR (Reação em Cadeia da Polimerase) e RFLP (Polimorfismo no Comprimento de Fragmentos de Restrição), e os amplicons positivos foram sequenciados. As porcentagens de similaridade relativas ao gene phoA de E. coli, para as cinco amostragens realizadas no estudo, apresentaram valores iguais ou superiores a 88,6%. As sequências de EPEC agruparam-se em diferentes clados com outras sequências do Brasil, Suíça e Uruguai, exibindo similaridade de 57,7 e 97,1% quando comparadas umas as outras. Quando comparadas a outras sequências de referência depositadas no GenBank, a similaridade variou entre 56,2 e 95,4%. Estes resultados são os primeiros a indicar a presença de EPEC em moluscos bivalves no Brasil. Astrovírus não foram identificados nas amostras de moluscos analisadas neste estudo. Norovírus (NoV) foi identificado em 21 (14%) das amostras, sendo 38% de mexilhões e 62% de ostras. As amostras de NoV genogrupo II (GII) foram agrupadas num clado único, juntamente com outras sequências de NoV GII, sendo mais próximas filogeneticamente de sequências originárias do Brasil, Japão e México, com similaridade de 93,8 a 96,6% do que com as outras sequências homólogas. A triagem de moluscos bivalves para coliformes, E. coli e presença de vírus entéricos significativos para a saúde pode ajudar na prevenção de surtos entre os consumidores e contribuir para a melhoria do ambiente estuarino. / The pathogenic bacteria in bivalve molluscs are causative agents of diseases such as gastroenteritis and responsible for several food-borne outbreaks, representing a risk to consumers. Enteric viruses are the most common cause of outbreaks of non-bacterial gastroenteritis in humans in the world and can be found in waters used in the cultivation of bivalve molluscs. The objective of this study was to evaluate the contamination of mussels (Mytella falcate) and oysters (Crassostrea brasiliana) from the estuarine complex Lagunar of Cananéia-Iguape, State of São Paulo, by bacteria (total coliforms, thermotolerant coliforms, Escherichia coli) and by human astroviruses and noroviruses. A total of 150 samples of bivalve molluscs (75 oysters and 75 mussels) were collected from June 2016 to February 2017. The total coliform estimate in oyster tissues varied from 14.1 to 154.5 most probable number (MPN)/g and thermotolerant coliforms from 3.0 to 48.6 MPN/g, whereas for mussel samples, total coliforms ranged from 97.4 to 1300 MPN/g and thermotolerant coliforms from 3.6 to 927 MPN/g. E. coli was detected in 24 samples (16%) at concentrations ranging from &lt;3 to &gt;927 NMP/g. Four (17%) were identified with enteropathogenic Escherichia coli (EPEC), presenting the gene eae by PCR (Polymerase Chain Reaction) and RFLP (Restriction fragment length polymorphism), and the positive amplicons were sequenced. The percentages of similarity relative to the phoA gene of E. coli, for the five samplings carried out in the study, presented values equal or superior to 88.6%. The EPEC sequences were grouped in different clades with other sequences from Brazil, Switzerland and Uruguay, exhibiting similarity of 57.7 and 97.1% when compared to each other. When compared to other reference sequences deposited in GenBank, the similarity ranged from 56.2 to 95.4%. These results are the first to indicate the presence of EPEC in bivalve molluscs in Brazil. Astroviruses were not identified in the mollusk samples analyzed in this study. Norovirus (NoV) was identified in 21 (14%) of the samples, representing 38% of mussels and 62% of oysters. NoV genogroup II (GII) samples were clustered in a single clade, along with other NoV GII sequences, keeping phylogenetically closest to sequences originating in Brazil, Japan and Mexico, with similarity of 93.8 to 96.6% than with the other homologous sequences. The screening of bivalve molluscs for coliforms, E. coli and the presence of enteric viruses significant to health can help preventing outbreaks among consumers and contribute to the improvement of the estuarine environment.

The CDC estimated that foodborne infections resulted in approximately 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths per year in the United States (Mead, 1999). There are over 200 known diseases caused by viruses, bacteria, parasites, toxins, metals, or prions that can be transmitted through food. Of these illnesses caused by foodborne disease, the CDC estimates that 38.6 million cases are from identifiable pathogens and 30.9 million of these cases are caused by viruses. Hence, approximately 80% of foodborne illnesses of known etiology result from viral transmission (Mead, 1999). Viral gastrointestinal illness may be caused by virus families such as: enterovirus, rotavirus, calicivirus, astrovirus, or norovirus. These viruses are highly contagious and are spread through the fecal-oral route; transmission vehicles include contaminated food or beverages, infected food handlers, fomites or close contact with an infected individual (FDA Bad Bug Book, 2003). Until recently, there have been few studies concentrating on viruses found in or on foods. There are several technical difficulties that hinder progress in detecting viral agents from foods. One of these problems is the presence of matrix inhibitors. Substances responsible for matrix inhibition include humic acid, polysaccharides, myoglobins, metal ions, glycogen, and lipids (Monpoeho, 2001). These substances in foods produce smearing of the RT-PCR amplicon bands on agarose gels. Several methods to reduce inhibitory compounds utilize multiple toxic reagents in the procedure. In this study, varying centrifugal forces were tested at different steps of the virus extraction/concentration procedure to reduce matrix inhibitory effects for molecular detection of norovirus and poliovirus seeded onto food surfaces. This method incorporates the rapid detection capabilities of RT-PCR with the ability to reduce or eliminate matrix inhibitors present in food, by altering the centrifugal force. Results for both viruses showed that band intensity decreased as the viral concentration decreased and no one method was superior for all food matrices. This investigation showed that matrix specific modifications to the basic protocol are required to efficiently extract viruses from the surface of foods. Each food should be assessed to determine modifications to the standard method that would be optimal for viral concentration and extraction.

Source: Masters Abstracts International, Volume: 45-05, page: 2450. Adviser: Herbert L. DuPont. Includes bibliographical references.

abstract: This thesis discusses the use of mass spectrometry and polymerase chain reaction (PCR), among other methods, to detect biomarkers of microorganisms in the environment. These methods can be used to detect bacteria involved in the degradation of environmental pollutants (bioremediation) or various single-celled pathogens, including those posing potential threats as bioterrorism agents. The first chapter introduces the hurdles in detecting in diverse environmental compartments in which they could be found, a select list of single-celled pathogens representing known or potential bioterrorism agents. These hurdles take the form of substances that interfere either directly or indirectly with the detection method. In the case of mass spectrometry-based detection, many of these substances (interferences) can be removed via effective sample pretreatment. Chapters 2 through 4 highlight specific methods developed to detect bioremediation or bioterrorism agents in environmental matrices. These methods are qualitative mass spectrometry, quantitative PCR, and quantitative mass spectrometry, respectively. The targeted organisms in these methods include several bioremediation agents, e.g. Pseudomonas putida F1 and Sphingomonas wittichii RW1, and bioterrorism agents, e.g. norovirus and Cryptosporidium parvum. In Chapter 2, I identify using qualitative mass spectrometry, biomarkers for three bacterial species involved in bioremediation. In Chapter 3, I report on a new quantitative PCR method suitable for monitoring of a key gene in yet another bioremediation agent, Sphingomonas wittichii RW1; furthermore, I apply this method to track the efficacy of bioremediation in bioaugmented environmental microcosms. In Chapter 4, I report on the development of new quantitative mass spectrometry methods for two organisms, S. wittichii RW1 and Cryptosporidium parvum, and evaluate two previously published methods for their applicability to the analysis of complex environmental samples. In Chapter 5, I review state-of-the-art methods for the detection of emerging biological contaminants, specifically viruses, in environmental samples. While this summary deals exclusively with viral pathogens, the advantages and remaining challenges identified are also applicable to all single-celled organisms in environmental settings. The suggestions I make at the end of this chapter are expected to be valid not only for future needs for emerging viruses but also for bacteria, eukaryotic pathogens, and prions. In general, it is advisable to continue the trend towards quantification and to standardize methods to facilitate comparison of results between studies. / Dissertation/Thesis / Ph.D. Biological Design 2012

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Rio de Janeiro, RJ, Brasil / Atualmente, os vírus entéricos, principalmente os norovírus humanos (NoV), são descritos como os principais causadores de surtos de doenças transmitidas por alimentos (DTA), especialmente os de rápido preparo e consumo, como frutas e frios. Devido às baixas concentrações de vírus entéricos em amostras de alimentos, é necessário dispor de um método de detecção rápido e eficiente que permita esclarecer surtos de origem alimentar e implementar medidas de prevenção quando necessárias. Este estudo teve como objetivo adaptar e avaliar a metodologia de floculação orgânica com leite desnatado para recuperação de vírus em frutas e queijos, comparando sucesso e eficiência de recuperação viral com outras metodologias previamente estabelecidas, assim como avaliar a qualidade microbiológica destes alimentos em municípios do Estado do Rio de Janeiro incluindo a pesquisa de vírus gastroentéricos. Ensaios de contaminação artificial em morangos, tomates e queijos foram realizados para recuperação de NoV GII.4 e norovírus murino 1 (MNV-1). O método de floculação orgânica por leite se mostrou eficiente para recuperação de NoV a partir de morangos e tomates quando comparado com métodos de polietileno glicol (PEG) e filtração por membranas carregadas negativamente. Entretanto, não se mostrou eficiente na recuperação viral em queijos, quando comparado com o método de extração direta por TRIzol® Para avaliação da qualidade microbiológica destes alimentos, 270 amostras (90 de cada matriz) obtidas comercialmente foram concentradas por floculação orgânica (morangos e tomates) e TRIzol® (queijos). Todas as amostras foram testadas por PCR quantitativo (qPCR) para investigação de NoV GI, GII e adenovírus humanos (HAdV). MNV-1 foi utilizado com sucesso como controle interno de processo em todas as reações. NoV foram identificados apenas nas amostras de queijos, enquanto a presença de HAdV foi observada em frutas e queijos. Adicionalmente foram realizadas analises bacteriológicas que revelaram coliformes termotolerantes em amostras de morangos e queijos. Nas amostras de queijos também se observou contaminação por Staphyloccocus coagulase positiva, abaixo dos padrões determinados pela legislação brasileira. Concluindo, os resultados obtidos neste estudo apresentam a metodologia de floculação orgânica como alternativa de baixo custo, para frutas, e o uso do TRIzol® em queijos que auxiliarão na vigilância laboratorial de surtos, gerando informações que permitam uma estimativa mais exata da proporção de surtos de NoV atribuídos a transmissão de origem alimentar / Currently, enteric víruses, primarily human norovírus (NoV), are described as the main cause of foodborne disease outbreaks (FBD), especially those of rapid preparation and consumption, like fruits and dairy. Due to the low concentrations of enteric vírus in food samples, it is necessary to have a fast and efficient detection method that allows to elucidate foodborne outbreaks and to implement preventive measures when necessary. This study aimed to adapt and evaluate the skimmed milk organic flocculation methodology for vírus recovery in fruits and cheeses, comparing success and the efficiency of viral recovery with other previously established methods, and assess the microbiological quality of food in the State of the Rio de Janeiro municipalities including gastroenteric vírus. Artificially contaminated strawberries, tomatoes and cheeses were evaluated for NoV GII.4 and murine norovírus 1 (MNV-1) recovery. The organic flocculation method was efficient for the NoV recovery from strawberries and tomatoes as compared to polyethylene glycol (PEG) and filtration negatively charged membranes. However, this methodology was not efficient for viral recovery in cheese when compared with the method of direct extraction by TRIzol® To evaluate the microbiological quality of food, 270 samples (90 of each matrix) commercially obtained were concentrated by organic flocculation (strawberries and tomatoes) and TRIzol® (cheese). All samples were assayed by quantitative PCR (qPCR) for investigation NoV GI, GII and human adenovírus (HAdV). MNV-1 was successfully used as an internal control process in all reactions. NoV were identified only in the cheeses samples, while the presence of HAdV was observed in fruits and cheese. In addition bacteriological analysis revealed that fecal coliforms in samples of strawberries and cheese. In cheese samples was also observed contamination for Staphylococcus coagulase positive below the Standards Brazilian. In conclusion, the results of this study present a skimmed milk organic flocculation methodology as a low cost alternative, for fruits, and the use of TRIzol® in cheeses that can assist in laboratory surveillance of outbreaks, generating information for a more accurate estimate of the proportion of NoV outbreaks attributed to foodborne transmission