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Adenoviruses (AdVs) have a significant impact in both medical and environmental contexts. The objective of this study was to investigate the prevalence of AdV in different water types, such as untreated and treated wastewater, surface water, groundwater, drinking water, and other water matrices. A total of 239 articles were included in this meta-analysis. Adenoviruses were detected in various waters worldwide. The overall prevalence in water was found to be 59.2%, with the highest prevalence in untreated wastewater (83.1%) and treated wastewater (75.3%), followed by "other water matrices" (53.4%), surface water (49.5%) drinking water (22.7%), and groundwater (18.5%). Most of the studies did not assess the viability of the viruses, leading to weak links between water contamination and risk. Both human and animal AdV were found in water environments. The findings suggest that water, including drinking water, could be a significant route of AdV transmission in both developed and developing economies.
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The COVID-19 epidemic is the latest in a long list of pandemics that have affected humankind in the last century. In this paper, we propose a novel mathematical epidemiological model named SUIHTER from the names of the seven compartments that it comprises: susceptible uninfected individuals (S), undetected (both asymptomatic and symptomatic) infected (U), isolated infected (I), hospitalized (H), threatened (T), extinct (E) and recovered (R). A suitable parameter calibration that is based on the combined use of the least-squares method and the Markov chain Monte Carlo method is proposed with the aim of reproducing the past history of the epidemic in Italy, which surfaced in late February and is still ongoing to date, and of validating SUIHTER in terms of its predicting capabilities. A distinctive feature of the new model is that it allows a one-to-one calibration strategy between the model compartments and the data that are made available daily by the Italian Civil Protection Department. The new model is then applied to the analysis of the Italian epidemic with emphasis on the second outbreak, which emerged in autumn 2020. In particular, we show that the epidemiological model SUIHTER can be suitably used in a predictive manner to perform scenario analysis at a national level.
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The Erice 56 Charter titled "Impact of the environment on the health: from theory to practice" was unanimously approved at the end of the 56th course of the "International School of Epidemiology and Preventive Medicine G. D'Alessandro" held from 3rd to November 7, 2019 in Erice - Sicily (Italy) and promoted by the Study Group of "Environment and Health" of the Italian Society of Hygiene, Preventive Medicine and Public Health. The course, that included lectures, open discussions and guided working groups, was aimed to provide a general training on epidemiological and toxicological aspects of the environmental health impact, to be used by public health professionals for risk assessment, without forgetting the risk communications. At the end of the course 12 key points were agreed among teachers and students: they underlined the need of specific training and research, in the perspective of "One Health" and "Global Health", also facing emerging scientific and methodological issues and focusing on communication towards stakeholders. This Discussion highlight the need to improve knowledge of Health and Environment topic in all sectors of health and environmental prevention and management.
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Salud Ambiental , Salud Pública , Salud Global , Humanos , SiciliaRESUMEN
Microbial safety of recreational waters is a significant public health issue. In this study we assessed the occurrence and quantity of enteric viruses in bathing and non-bathing waters in Italy, in parallel with microbial faecal indicators, somatic coliphages and Vibrio spp. Enteric viruses (aichivirus, norovirus and enterovirus) were detected in 55% of bathing water samples, including samples with bacterial indicator concentrations compliant with the European bathing water Directive. Aichivirus was the most frequent and abundant virus. Adenovirus was detected only in non-bathing waters. Somatic coliphages were identified in 50% bathing water samples, 80% of which showed simultaneous presence of viruses. Vibrio species were ubiquitous, with 9 species identified, including potential pathogens (V. cholerae, V. parahaemoylticus and V. vulnificus). This is the first study showing the occurrence and high concentration of Aichivirus in bathing waters and provides original information, useful in view of a future revision of the European Directive.
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Playas , Agua de Mar/microbiología , Agua de Mar/virología , Colifagos , Enterovirus , Monitoreo del Ambiente , Heces/microbiología , Heces/virología , Humanos , Italia , Mar Mediterráneo , Norovirus/genética , Norovirus/aislamiento & purificación , Vibrio/genética , Vibrio/aislamiento & purificación , Vibrio/patogenicidad , Microbiología del AguaRESUMEN
BACKGROUND: The Mediterranean diet (MD) is considered one of the healthiest dietary models, as it decreases the risk of chronic diseases and may modulate the organism's early response to environmental pollution. In recent decades, Mediterranean countries have been replacing their traditional diet with other less healthy eating habits, especially among children and teenagers. OBJECTIVE: The aim of this study was to evaluate the MD and the level of adherence to it in 6-8 year old Italian children, in relation to residence, lifestyle, and social and family contexts. METHODS: A questionnaire was administered to the children's parents in two seasons in 5 Italian towns. The diet section contained 116 questions investigating the frequency of consumption of different types of food. The Italian Mediterranean Index (IMI) was calculated according to the intake of 6 typical Mediterranean and 4 non-Mediterranean foods. On the basis of IMI score, MD adherence was classified as low (≤ 3 IMI score), medium (4-5) and high (≥ 6). Total energy load and diet composition in micro- and macronutrients were calculated from consumption frequency. RESULTS: Diet analysis was computed on 1164 subjects with two complete questionnaires. Body mass index, calculated for each subject, showed that 28.9% of the children were overweight, the figure varying slightly with area of residence. Our findings showed that 59.0% of the children had a low score for MD adherence. CONCLUSIONS: The results of this study showed that most Italian children did not follow the MD and socio-economic characteristics appeared not to be associated with type of diet.
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Dieta Mediterránea , Estilo de Vida , Sobrepeso/epidemiología , Padres , Cooperación del Paciente/estadística & datos numéricos , Adulto , Índice de Masa Corporal , Niño , Encuestas sobre Dietas , Conducta Alimentaria , Femenino , Humanos , Italia/epidemiología , Masculino , Obesidad Infantil/epidemiología , Pobreza/estadística & datos numéricos , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
Bacterial indicator organisms are used globally to assess the microbiological safety of waters. However, waterborne viral outbreaks have occurred in drinking water systems despite negative bacterial results. Using viral markers may therefore provide more accurate health risk assessment data. In this study, fecal, wastewater, stormwater, surface water (fresh and salt), groundwater, and drinking water samples were analyzed for the presence or concentration of traditional indicators, innovative indicators and viral markers. Samples were obtained in the United States, Italy, and Australia and results compared to those reported for studies conducted in Asia and South America as well. Indicators included total coliforms, Escherichia coli, enterococci, male-specific coliphages, somatic coliphages and microviradae. Viral markers included adenovirus, polyomavirus, and a potential new surrogate, Torque teno virus (TTV). TTV was more frequently found in wastewaters (38-100%) and waters influenced by waste discharges (25%) than in surface waters used as drinking water sources (5%). TTV was also specific to human rather than animal feces. While TTV numbers were strongly correlated to other viral markers in wastewaters, suggesting its utility as a fecal contamination marker, data limitations and TTV presence in treated drinking waters demonstrates that additional research is needed on this potential viral indicator.
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Salud Global , Torque teno virus/genética , Torque teno virus/aislamiento & purificación , Microbiología del Agua , Animales , Australia , Colifagos/genética , Colifagos/aislamiento & purificación , Heces/virología , Humanos , Italia , Vigilancia en Salud Pública , Estados Unidos , Aguas Residuales/virología , Abastecimiento de AguaRESUMEN
INTRODUCTION: The MAPEC-Life project aims to study the biological effects of early exposure to air pollutants on the oral mucosa cells of school-age children in five Italian cities. A questionnaire was created to evaluate the association between outdoor and indoor airborne pollutants, lifestyle, diet and biomarker effects. The feasibility and reliability of the questionnaire were evaluated. METHODS: A questionnaire was drawn up to be filled in by the parents of 6-8-year-old children. It consisted of 148 questions on the children's health, physical activity, environmental exposures and the frequency of food consumption at the main meals. First we conducted a questionnaire feasibility study involving 53 volunteer parents. We then performed a reliability study by administering the questionnaire to a further 156 parents and again one month later (test/retest method). The correlations between answers at the first and second administration of the questionnaire were evaluated using the Kappa statistic and Spearman's coefficient. RESULTS: After verifying the feasibility of the questionnaire, we conducted a reliability analysis on 132 completed questionnaires. The percentage of agreement between the first and the second responses given was over 70%, all K values being greater than 0.6. The analysis of calories and macronutrients also showed good agreement. CONCLUSIONS: The questionnaire drawn up for the study proved to be sufficiently reliable for gathering information about the factors of interest in our study of the relationship between air pollution and early biological effects in children.
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Contaminación del Aire Interior , Dieta , Exposición a Riesgos Ambientales , Estado de Salud , Actividad Motora , Encuestas y Cuestionarios , Contaminación del Aire Interior/efectos adversos , Niño , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Estudios de Factibilidad , Femenino , Encuestas Epidemiológicas , Humanos , Italia , Masculino , Padres , Reproducibilidad de los ResultadosRESUMEN
INTRODUCTION: Genotoxic biomarkers have been studied largely in adult population, but few studies so far have investigated them in children exposed to air pollution. Children are a high-risk group as regards the health effects of air pollution and some studies suggest that early exposure during childhood can play an important role in the development of chronic diseases in adulthood. The objective of the project is to evaluate the associations between the concentration of urban air pollutants and biomarkers of early biological effect in children, and to propose a model for estimating the global risk of early biological effects due to air pollutants and other factors in children. METHODS AND ANALYSIS: Two biomarkers of early biological effects, DNA damage by the comet assay and the micronuclei (MN) test, will be investigated in oral mucosa cells of 6-8-year-old children. Concurrently, some toxic airborne pollutants (polycyclic aromatic hydrocarbon (PAH) and nitro-PAH) and in vitro air mutagenicity and toxicity in ultra-fine air particulates (PM0.5) will be evaluated. Furthermore, demographic and socioeconomic variables, other sources of exposures to air pollutants and lifestyle variables will be assessed by a structured questionnaire. The associations between sociodemographic, environmental and other exposure variables and biomarkers of early biological effect using univariate and multivariate models will be analysed. A tentative model for calculating the global absolute risk of having early biological effects caused by air pollution and other variables will be proposed. ETHICS AND DISSEMINATION: The project has been approved by the Ethics Committees of the local Health Authorities. The results will be communicated to local Public Health Agencies, for supporting educational programmes and health policy strategies. LIFE+2012 Environment Policy and Governance. LIFE12 ENV/IT/000614.
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Contaminación del Aire/análisis , Monitoreo del Ambiente , Política de Salud , Salud Pública , Niño , Humanos , Estudios ProspectivosRESUMEN
The purpose of wastewater treatment is to minimize chemical and microbial contamination of recipient waters. The present study evaluated the impacts of meteorological variables, such as temperature and rainfall, on the removal of human viruses and indicators by a wastewater treatment plant servicing Pisa, Italy. Data were obtained during four sampling campaigns from 2007 to 2010. Wastewater sewage samples were analyzed for human adenovirus (HAdV) and norovirus using quantitative molecular techniques. In parallel, Escherichia coli, enterococci and somatic coliphages were measured, and meteorological and chemical data were recorded. We detected a continuous presence of HAdV in both influent and effluent samples with an average removal rate of 2.01 log10 Genomic Copies/l. An association between meteorological parameters and viral removal rates was detected only for rainfall and HAdV removal during a specific sampling campaign. No correlation was found between viral data and microbial, chemical and physical ones. Viral removal rates were not strongly influenced by meteorological conditions and were unrelated to other process indicators routinely monitored. Our results suggest that HAdV is a suitable parameter to assess the viral removal efficiency of wastewater treatment plants, particularly in the case of heavy rainfall.
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Adenovirus Humanos/aislamiento & purificación , Colifagos/aislamiento & purificación , Enterococcus/aislamiento & purificación , Monitoreo del Ambiente/métodos , Escherichia coli/aislamiento & purificación , Norovirus/aislamiento & purificación , Italia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Aguas del Alcantarillado/virología , Microbiología del Agua , Purificación del Agua/métodosRESUMEN
Temperature is considered as the major factor determining virus inactivation in the environment. Food industries, therefore, widely apply temperature as virus inactivating parameter. This review encompasses an overview of viral inactivation and virus genome degradation data from published literature as well as a statistical analysis and the development of empirical formulae to predict virus inactivation. A total of 658 data (time to obtain a first log(10) reduction) were collected from 76 published studies with 563 data on virus infectivity and 95 data on genome degradation. Linear model fitting was applied to analyse the effects of temperature, virus species, detection method (cell culture or molecular methods), matrix (simple or complex) and temperature category (<50 and ≥50°C). As expected, virus inactivation was found to be faster at temperatures ≥50°C than at temperatures <50°C, but there was also a significant temperature-matrix effect. Virus inactivation appeared to occur faster in complex than in simple matrices. In general, bacteriophages PRD1 and PhiX174 appeared to be highly persistent whatever the matrix or the temperature, which makes them useful indicators for virus inactivation studies. The virus genome was shown to be more resistant than infectious virus. Simple empirical formulas were developed that can be used to predict virus inactivation and genome degradation for untested temperatures, time points or even virus strains.
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Enterovirus/fisiología , Microbiología de Alimentos , Inactivación de Virus , Microbiología del Agua , Daño del ADN , Enterovirus/genética , Microbiología de Alimentos/métodos , Genoma Viral , TemperaturaRESUMEN
The presence of pathogenic viruses in healthcare settings represents a serious risk for both staff and patients. Direct viral detection in the environment poses significant technical problems and the indirect indicators currently in use suffer from serious limitations. The aim of this study was to monitor surfaces and air in hospital settings to reveal the presence of hepatitis C virus, human adenovirus, norovirus, human rotavirus and torque teno virus by nucleic acid assays, in parallel with measurements of total bacterial count and haemoglobin presence. In total, 114 surface and 62 air samples were collected. Bacterial contamination was very low (<1 cfu/cm(2)) on surfaces, whereas the 'medium' detected value in air was 282 cfu/m(3). Overall, 19 (16.7%) surface samples tested positive for viral nucleic acids: one for norovirus, one for human adenovirus and 17 (14.9%) for torque teno virus (TTV). Only this latter virus was directly detected in 10 air samples (16.1%). Haemoglobin was found on two surfaces. No relationship was found between viral, biochemical or bacterial indicators. The data obtained confirm the difficulty of assessing viral contamination using bacterial indicators. The frequent detection of TTV suggests its possible use as an indicator for general viral contamination of the environment.
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Microbiología del Aire , Bacterias/aislamiento & purificación , Monitoreo del Ambiente/métodos , Ambiente de Instituciones de Salud , Virus/aislamiento & purificación , Recuento de Colonia Microbiana , Infección Hospitalaria/prevención & control , Hemoglobinas/análisis , Hospitales , Humanos , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Propiedades de Superficie , Virus/genéticaRESUMEN
AIMS: The purpose of this work was to verify whether E. coli is a good indicator of viral contamination in mussels and Adenovirus could represent a better alternative as indicator organism of viral presence to guarantee consumer health protection. METHODS AND RESULTS: Eighty samples of mussels from La Spezia Gulf were analysed for E. coli, Salmonella, Adenovirus, Norovirus and hepatitis A virus with cultural and biomolecular tests. The results of bacterial parameters showed E. coli within the law's limits and the absence of Salmonella. Twelve samples were positive for Adenovirus presence, one for Norovirus genogroup II and two for hepatitis A virus. None of these positive mussels was found to be contaminated with more than one virus at the same time. CONCLUSION: This study showed that there was not a direct correlation between the presence of human pathogenic viruses and bacterial indicators. SIGNIFICANCE AND IMPACT OF THE STUDY: Both E. coli and Adenovirus cannot be considered valid substitutes for the direct research of human pathogenic viruses in mussels. To improve consumer health protection, the European Commission will provide standardized methods for Norovirus and hepatitis A virus detection as soon as possible.
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Adenoviridae/aislamiento & purificación , Bivalvos/microbiología , Bivalvos/virología , Escherichia coli/aislamiento & purificación , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Mariscos/microbiología , Mariscos/virología , Adenoviridae/genética , Animales , Seguridad de Productos para el Consumidor , Enterovirus/genética , Enterovirus/aislamiento & purificación , Escherichia coli/genética , ItaliaRESUMEN
AIMS: Legionella contamination of industrial cooling towers has been identified as the cause of sporadic cases and outbreaks of legionellosis among people living nearby. To evaluate and control Legionella contamination in industrial cooling tower water, microbiological monitoring was carried out to determine the effectiveness of the following different disinfection treatments: (i) continuous chlorine concentration of 0.01 ppm and monthly chlorine shock dosing (5 ppm) on a single cooling tower; (ii) continuous chlorine concentration of 0.4 ppm and monthly shock of biocide P3 FERROCID 8580 (BKG Water Solution) on seven towers. METHODS AND RESULTS: Legionella spp. and total bacterial count (TBC) were determined 3 days before and after each shock dose. Both strategies demonstrated that when chlorine was maintained at low levels, the Legionella count grew to levels above 10(4) CFU l(-1) while TBC still remained above 10(8 )CFU l(-1). Chlorine shock dosing was able to eliminate bacterial contamination, but only for 10-15 days. Biocide shock dosing was also insufficient to control the problem when the disinfectant concentration was administered at only one point in the plant and at the concentration of 30 ppm. On the other hand, when at a biocide concentration of 30 or 50 ppm was distributed throughout a number of points, depending on the plant hydrodynamics, Legionella counts decreased significantly and often remained below the warning limit. Moreover, the contamination of water entering the plant and the presence of sediment were also important factors for Legionella growth. CONCLUSIONS: For effective decontamination of outdoor industrial cooling towers, disinfectants should be distributed in a targeted way, taking into account the possible sources of contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: The data of the research permitted to modify the procedure of disinfection for better reduce the water and aerosol contamination and consequently the exposure risk.
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Cloro , Desinfectantes , Industrias , Legionella/crecimiento & desarrollo , Microbiología del Agua , Recuento de Colonia Microbiana , Reservorios de Enfermedades , Desinfección/métodos , Legionella pneumophila/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Purificación del Agua/métodosRESUMEN
Municipal and agricultural wastewater contain a variety of microorganisms and in particular enteric viruses. For the reuse of this treated wastewater it is important to ensure the efficiency of purification treatments and disinfection practices, that have often been insufficient to lower the viral load below the risk level. For this reason, for the routine analysis of recycled waters, the research into pathogenic viruses (e.g. HAV) and classical bacterial parameters (E. coli, enterococci and Salmonella) has to be associated with specific viral indicators such as somatic coliphages, adenovirus and TTV. The results of environmental monitoring, carried out in a wastewater treatment plant, showed the presence of adenovirus DNA in 100% of collected samples and TTV DNA in 95% (19/20) of raw sewage and in 85% (17/20) of the exit samples, while HAV was detected only in 2 samples over 40 (5%). The quantitative analysis has revealed an average reduction of 2 log for adenovirus and 1.58 log for TTV. The bacterial indicators were reduced by 1.74 log and 1.99 log respectively for E. coli and enterococci, while for somatic coliphages an average reduction of 2.2 log was observed. No significant correlation was shown between these parameters, confirming their inadequacy for the virological risk assessment. However the results of adenovirus confirm it as the best indicator to evaluate the efficacy of wastewater depuration plant in eliminating viruses.
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Aguas del Alcantarillado/virología , Virus/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Adenoviridae/aislamiento & purificación , Ciudades , Monitoreo del Ambiente , Microbiología del AguaRESUMEN
Torque teno virus (TTV) is prevalent worldwide in general populations but at present is not related with any specific pathology. Its presence in faeces and its remarkable environmental stability suggest the possibility of using it as an indicator of faecal contamination in the environment. To evaluate the waterborne spread of TTV and its possible relationship with human pathogen enteric viruses, water samples were collected monthly for a year (May 2004-April 2005) from a river receiving the effluent of the treatment plant of the city of Pisa, concentrated and assayed with bimolecular tests (PCR, RT-PCR). TTV was detected in three samples (25%) while 16% of samples were positive for enteroviruses, 33% for rotaviruses, 8% for noroviruses genotype 1 and 25% for noroviruses genotype 2. Only two TTV samples (June and January) were also positive for rotavirus and norovirus, respectively. The detection of TTV in water confirmed its possible faecal-oral route of transmission but data are still insufficient to draw conclusions about the role of TTV as a viral indicator.
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Reacción en Cadena de la Polimerasa/métodos , Torque teno virus/aislamiento & purificación , Microbiología del Agua , Secuencia de Bases , Cartilla de ADN , Italia , RíosRESUMEN
In the aim of studying possible relations between viruses detected in clinical specimens and the ones found in different environmental matrices, in the period May 2004 to April 2005, the collection of faecal samples from gastroenteritis cases and the monthly monitoring of raw and treated wastewater, river water, seawater and mussels were carried out. The viruses considered for environmental monitoring were adenovirus, rotavirus, enterovirus, norovirus, hepatitis A virus (HAV) and Torque teno virus (TTV): they were searched for with PCR and RT-PCR and confirmed by gene sequencing. Faecal coliforms and somatic coliphages' counts were also determined. The surveillance of case detected 45 positive faecal samples out of 255 (17.6%) while 35 of 56 environmental samples (62.5%) resulted positive for at least one of the considered viruses. The detection of the same viral strain in the faeces of gastroenteritis cases and in water was possible for adenovirus and rotavirus, which were also predominant in environmental matrices; thus they could be considered as a reference for risk assessment.
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Enterovirus/aislamiento & purificación , Monitoreo del Ambiente , Estudios Epidemiológicos , Microbiología del Agua , Secuencia de Bases , Cartilla de ADN , Enterovirus/genética , Heces/virología , Reacción en Cadena de la PolimerasaRESUMEN
Surveys on life and health conditions of university students besides providing useful epidemiologic data partly related to the young population. They are potentially useful for the intervention planning aimed to remove possible environmental or behavioural risk factors. Following these purpose a survey sample about 1200 student attending the University of Pisa was carried out through an anonymous questionnaire about 41 questions focused on behaviours and lifestyles of young people, possible health problems, self-perception of the health state, the use of public health services, and the more commonly used (or preferred) sources of information on health topics. The results suggest that although the self perception of the state of health is broadly positive for the majority of students, there is also a significant frequency of individuals declaring significant at risk behaviours (persistence of sexual practices at risk, drug use, alcohol and smoke abuse). The consumption, also sporadic, of psicoattive substances has been declared gives beyond 40% of the students, in particular 37% asserts to have tried drugs. The habit to smoke appeared diffused much between the students; the percentage of smokers turns out equal to 41% in total (40% females, 42% males). 76% of the interviewed ones has declared to be sexually active, the percentage of those who have declared multiple relations or occasional is elevated (12%), and 47% of the students asserts to use the condom with fixed partner and 77% with occasional partner. Moreover there seems to be a significant association between the changes in the diet and other lifestyles that are due to the "university lifestyle" (as a consequence of leaving the family or increased commuting) and the insurgence of several types of sickness, e.g. gastroenteric disturbances and fever attacks. Finally, the present investigation suggests that few interventions on services offered to students (such as accommodation, teaching structures and especially the creation of a "health office" where students can acquire information on health and other topics related to their condition) could have a significantly beneficial impact on the general state of health of the university population.
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Estado de Salud , Estilo de Vida , Estudiantes , Adulto , Ambiente , Femenino , Humanos , Italia , Masculino , Conducta SexualRESUMEN
The present study was performed in order to obtain reliable and applicable techniques of viral detection in shellfish for use in ensuring food safety. This research was developed in two steps: (a) different techniques to recover viruses from artificially contaminated shellfish were tested and (b) the best technique was applied to analyse shellfish collected from sites along the coast of Salento.
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Contaminación de Alimentos , Seguridad , Mariscos/virología , Virus/genética , Animales , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y EspecificidadRESUMEN
This work was aimed at studying cytopathogenic agents isolated from the environment by adopting, in parallel, various techniques currently used in clinical virology. The purpose of this research was not only to identify the viral species isolated but also to verify the most reliable protocols for environmental applications.
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Monitoreo del Ambiente/métodos , Virología/métodos , Virus/genética , Microbiología del Agua , ADN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Deep groundwater, even if generally protected, could be contaminated by surface or rain water infiltration through soil fractures, septic tanks, cesspits, land irrigation, disposal of wastewater and disposal of muds from depuration systems. The sanitary importance of such possible contamination is related to the different uses of the water and it is at the maximum level when it is intended for human use. Routine microbiological analyses do not consider viruses, only bacterial parameters, as contamination indicators. However, it is known that enteric viruses can survive a long time in deep aquifers and that they may not always be associated with bacterial indicators. The virological analysis of waters intended for drinking use is provided only as an occasional control exercised at the discretion of the sanitary authority. Technological difficulties with obtaining data about groundwater viral contamination led to a study to devise rapid and efficient methods for their detection and the application of these methods to samples from different sources. Four acid nucleic extraction techniques have been tested (classic proteinase K- phenol/chloroform, QIAamp Viral RNA Kit (Qiagen), SV Total RNA Isolation System (Promega) and NucleoSpin Virus L (Macherey-Nagel). Sensitivity and specificity of RT-PCR protocols for entero- (EV), hepatitis A (HAV) and small round structured (SRSV) viruses have been verified. Deep groundwater samples (100 L) were concentrated (2-step tangential flow ultrafiltration) and the concentrate contaminated with serial 10-fold dilutions of a known titre of poliovirus type 3. Extracted RNA was concentrated (microcon-100) and analysed by RT-PCR using specific EV primers and visualising amplification products by agarose gel electrophoresis. In addition, two different methods of RT-PCR for non-cultivable viruses have been tested: (a) RT-PCR and nested RT-PCR for HAV and (b) RT-PCR with generic primers and RT-PCR with specific primers for SRSV. Different specificity tests have been carried out in the presence of some of the commoner microorganisms. The most efficient, sensitive and specific protocols were used to test 35 x 100L deep groundwater samples. Sample concentrates were split with one part treated with chloroform and analysed by cell culture (BGM and Frp/3, derived from FrHK/4, cells) and the other tested by RT-PCR for HAV, EV and SRSV. Results demonstrated the high efficiency of the classic and QIAamp methods. Microcon-100 did not increase the sensitivity of the technique used. The highest sensitivity was observed for RT-PCR with specific primers for SRSV and for nested RT-PCR for HAV. One sample showed a cytopathic effect, not confirmed at the third subculture, while the RT-PCR allowed the detection of echovirus 7. Cell culture did not allow detection of the majority of the enteric viruses while PCR gave sensitive, specific and rapid detection of a range of agents in the same samples. Even if it was impossible to fix a virological quality standard, it would be necessary to find a viral indicator in order to achieve a complete preventive check which would be particularly useful in some cases (e.g. water never used before, after pollution accidents, for seasonal checking).