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1.
Mem. Inst. Oswaldo Cruz ; 115: e200196, 2020. tab, graf
Artigo em Inglês | LILACS, SES-SP | ID: biblio-1135230

RESUMO

This study presents preliminary results from a sewage-based surveillance to monitor the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the municipality of Niterói, State of Rio de Janeiro, Brazil. By using ultracentrifugation method associated to quantitative reverse transcription polymerase chain reaction (RT-qPCR) we detected SARS-CoV-2 in 41.6% (5/12) of raw sewage samples obtained from sewage treatment plants and sewers network in the city. This pioneer study carried out in Brazil aims to subsidise information for health surveillance concerning the viral circulation in different areas of the city and, revealed the insertion and importance of environmental virology in health public policies.


Assuntos
Humanos , Pneumonia Viral/epidemiologia , Esgotos/virologia , Infecções por Coronavirus/epidemiologia , Betacoronavirus/isolamento & purificação , Ultracentrifugação , Brasil , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pandemias , SARS-CoV-2 , COVID-19
2.
Braz. j. biol ; 77(3): 459-468, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888790

RESUMO

Abstract The human polyomaviruses JC and BK (JCPyV and BKPyV) are ubiquitous, species-specific viruses that belong to the family Polyomaviridae. These viruses are known to be excreted in human urine, and they are potential indicators of human wastewater contamination. In order to assess the distribution of both JCPyV and BKPyV in urban water samples collected from a sewage treatment plant (STP) and from a canalized water stream of Porto Alegre, Brazil, two nested-PCR assays were optimized and applied to the samples collected. The amplicons obtained were submitted to sequencing, and the sequences were analyzed with sequences of human polyomaviruses previously deposited in GenBank. Twelve out of 30 water samples (40%) were JCPyV positive, whereas six samples (20%) were BKPyV positive. The sequencing results confirmed the presence of JCPyV subtypes 1 and 3, whereas only BKPyV Ia and Ib were found. This study shows for the first time the presence of human polyomaviruses in surface water and in samples collected in a sewage treatment plant in southern Brazil.


Resumo Os poliomavírus humanos JC e BK (JCPyV e BKPyV) são virus ubíquos, espécie-específicos, pertencentes à família Polyomaviridae. Estes vírus são conhecidos por serem excretados pela urina humana, sendo considerados potenciais indicadores de contaminação por águas residuais urbanas. Buscando acessar a distribuição de JCPyV e BKPyV em amostras de águas coletadas de uma estação de tratamento de esgoto e de um arroio canalizado de Porto Alegre, Brasil, duas técnicas de nested-PCR foram otimizadas e aplicadas às amostras coletadas. Os amplificados obtidos foram submetidos ao sequenciamento e suas sequências analisadas com base em sequências de poliomavírus humanos previamente depositadas no GenBank. Doze de 30 amostras de água (40%) foram positivas para JCPyV, enquanto 6 amostras (20%) foram positivas para BKPyV. Os resultados do sequenciamento confirmaram a presença dos subtipos 1 e 3 de JCPyV, enquanto apenas os BKPyV Ia e Ib foram encontrados. Este estudo demonstra pela primeira vez a presença de poliomavírus humanos em águas superficiais e em amostras coletadas em uma estação de tratamento de esgoto na região sul do Brasil.


Assuntos
Esgotos/virologia , Vírus BK/isolamento & purificação , Vírus BK/genética , Vírus JC/isolamento & purificação , Vírus JC/genética , Água Doce/virologia , Variação Genética , Brasil , Reação em Cadeia da Polimerase
3.
Mem. Inst. Oswaldo Cruz ; 112(3): 175-181, Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841776

RESUMO

BACKGROUND Two novel viruses named circo-like virus-Brazil (CLV-BR) hs1 and hs2 were previously discovered in a Brazilian human fecal sample through metagenomics. CLV-BR hs1 and hs2 possess a small circular DNA genome encoding a replication initiator protein (Rep), and the two genomes exhibit 92% nucleotide identity with each other. Phylogenetic analysis based on the Rep protein showed that CLV-BRs do not cluster with circoviruses, nanoviruses, geminiviruses or cycloviruses. OBJECTIVE The aim of this study was to search for CLV-BR genomes in sewage and reclaimed water samples from the metropolitan area of São Paulo, Brazil, to verify whether the first detection of these viruses was an isolated finding. METHODS Sewage and reclaimed water samples collected concomitantly during the years 2005-2006 were purified and concentrated using methodologies designed for the study of viruses. A total of 177 treated reclaimed water samples were grouped into five pools, as were 177 treated raw sewage samples. Nucleic acid extraction, polymerase chain reaction (PCR) amplification and Sanger sequencing were then performed.e FINDINGS CLV-BR genomes were detected in two pools of sewage samples, p6 and p9. Approximately 28% and 51% of the CLV-BR genome was amplified from p6 and p9, respectively, including 76% of the Rep gene. The detected genomes are most likely related to CLV-BR hs1. Comparative analysis showed several synonymous substitutions within Rep-encoding sequences, suggesting purifying selection for this gene, as has been observed for other eukaryotic circular Rep-encoding single-stranded DNA (CRESS-DNA) viruses. MAIN CONCLUSION The results therefore indicated that CLV-BR has continued to circulate in Brazil two and three years after first being detected.


Assuntos
Humanos , Esgotos/virologia , DNA Viral/genética , Reação em Cadeia da Polimerase , Circovirus/isolamento & purificação , Circovirus/genética , Filogenia , Genoma Viral , Análise de Sequência
4.
Braz. j. microbiol ; 46(3): l7235-723, July-Sept. 2015. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1469613

RESUMO

Adenoviruses are among the most promising viral markers of fecal contamination. They are frequently found in the water, sediment and soil of regions impacted by human activity. Studies of the bioaccumulation of enteric viruses in shrimp are scarce. The cities located in the northern coast of the lake systems in Southern Brazil have high urbanization and intensive farming rates, and poor sewage collection and treatment. One hundred (n = 100) Farfantepenaeus paulensis pink-shrimp specimens and 48 water samples were collected from coastal lagoons between June 2012 and May 2013. Water samples were concentrated and the shrimp, mashed. After DNA extraction, samples were analyzed by real time polymerase chain reaction (qPCR) in order to detect and quantify viral genomes. Thirty-five percent of shrimp samples were positive for contamination, predominantly by avian adenoviruses. A total of 91.7% of water samples contained adenoviruses DNA, with the human form being the most frequent. Our results provided evidence of significant bioaccumulation of adenoviruses in shrimp, showing the extent of the impact of fecal pollution on aquatic ecosystems..


Assuntos
Animais , Adenoviridae/classificação , Adenoviridae/isolamento & purificação , Fezes/virologia , Penaeidae/virologia , Poluição da Água , Brasil , Ecossistema , Esgotos/virologia , Geografia , Reação em Cadeia da Polimerase em Tempo Real
5.
Braz. j. microbiol ; 46(3): 715-723, July-Sept. 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-755819

RESUMO

Adenoviruses are among the most promising viral markers of fecal contamination. They are frequently found in the water, sediment and soil of regions impacted by human activity. Studies of the bioaccumulation of enteric viruses in shrimp are scarce. The cities located in the northern coast of the lake systems in Southern Brazil have high urbanization and intensive farming rates, and poor sewage collection and treatment. One hundred (n = 100) Farfantepenaeus paulensis pink-shrimp specimens and 48 water samples were collected from coastal lagoons between June 2012 and May 2013. Water samples were concentrated and the shrimp, mashed. After DNA extraction, samples were analyzed by real time polymerase chain reaction (qPCR) in order to detect and quantify viral genomes. Thirty-five percent of shrimp samples were positive for contamination, predominantly by avian adenoviruses. A total of 91.7% of water samples contained adenoviruses DNA, with the human form being the most frequent. Our results provided evidence of significant bioaccumulation of adenoviruses in shrimp, showing the extent of the impact of fecal pollution on aquatic ecosystems.

.


Assuntos
Animais , Adenoviridae/classificação , Adenoviridae/isolamento & purificação , Fezes/virologia , Penaeidae/virologia , Poluição da Água , Brasil , Ecossistema , Geografia , Reação em Cadeia da Polimerase em Tempo Real , Esgotos/virologia
6.
Cad. saúde pública ; 30(7): 1367-1378, 07/2014. tab
Artigo em Português | LILACS | ID: lil-720545

RESUMO

Os serviços de saneamento básico têm papel fundamental no controle da transmissão de diversos agentes patogênicos de veiculação hídrica, especialmente vírus responsáveis por causar gastroenterites agudas e hepatites. Entre os agentes virais de maior impacto para a saúde pública, podem ser destacados os vírus das hepatites A, os rotavírus e norovírus, adenovírus e enterovírus, os quais são responsáveis pela contaminação de diversos ecossistemas aquáticos brasileiros. A alta circulação de vírus no ambiente vem sendo relacionada às condições sanitárias inadequadas das comunidades, incluindo a falta na cobertura de serviços ou ineficácia de tecnologias convencionais na eliminação ou redução da carga viral presente na água ou no esgoto. Este estudo aborda uma revisão das relações entre virologia, saúde e saneamento, enfatizando a epidemiologia das infecções virais de transmissão hídrica e o impacto na saúde pública.


Sanitation services play a critical role in controlling transmission of numerous waterborne pathogens, especially viruses that cause acute gastroenteritis and hepatitis. The viral agents with the greatest public health impact are hepatitis A virus, rotaviruses and noroviruses, adenoviruses, and enteroviruses, contaminating many Brazilian aquatic ecosystems. Heavy circulation of viruses in the environment has been related to inadequate local sanitary conditions, including incomplete coverage of services or inefficacy of conventional technologies in eliminating or reducing the viral load in water or sewage. This study reviews the relations between virology, health, and sanitation, emphasizing the epidemiology of waterborne viral infections and their public health impact.


El servicio de saneamiento posee un rol en el control de la transmisión de muchos patógenos transmitidos por el agua, especialmente aquellos virus responsables de causar gastroenteritis aguda y hepatitis. Entre los agentes virales de mayor impacto sobre la salud pública se pueden destacar los virus de la hepatitis A, rotavirus, norovirus, adenovirus y enterovirus, los cuales son responsables de la contaminación de diversos ecosistemas acuáticos brasileños. Una alta circulación del virus en el medio ambiente se relaciona con condiciones sanitarias inadecuadas de las comunidades, como la falta de cobertura de los servicios o la ineficacia de las tecnologías convencionales en eliminar la carga viral del agua. Esta revisión está enfocada en las relaciones entre la virología, la salud y el saneamiento, con énfasis en la epidemiología de las infecciones virales transmitidas por el agua y el impacto en la salud pública.


Assuntos
Humanos , Saneamento/estatística & dados numéricos , Esgotos/virologia , Viroses/transmissão , Vírus/classificação , Microbiologia da Água , Abastecimento de Água , Brasil , Saneamento/normas , Viroses/prevenção & controle
7.
Braz. j. microbiol ; 45(1): 343-349, 2014. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1469609

RESUMO

Human enteric viruses are responsible to cause several diseases, including gastroenteritis and hepatitis, and can be present in high amounts in sewage sludge. This study compared virus recovery efficiency of two feasible concentration methods used for detecting human adenovirus (HAdV), rotavirus species A (RV-A), norovirus genogroup II (NoV GII) and hepatitis A virus (HAV) in sewage sludge from an activated sludge process. Twelve sewage sludge samples were collected bi-monthly from January to July, 2011. Ultracentrifugation was compared with a simplified protocol based on beef extract elution for recovering enteric viruses. Viruses were quantified by quantitative real-time PCR assays and virus recovery efficiency and limits of detection were determined. Methods showed mean recovery rates lower than 7.5%, presenting critical limits of detection (higher than 102 103 genome copies -GC L-1 for all viruses analyzed). Nevertheless, HAdV were detected in 90% of the analyzed sewage sludge samples (range: 1.8 x 104 to 1.1 x 105 GC L-1), followed by RV-A and NoV (both in 50%) and HAV (8%). Results suggesting that activated sludge is contaminated with high viral loads and HAdV are widely disseminated in these samples. The low virus recovery rates achieved, especially for HAV, indicate that other feasible concentration methods could be developed to improve virus recovery efficiency in these environmental matrices.


Assuntos
Carga Viral , Esgotos/virologia , Lodos Ativados , Vírus
8.
Mem. Inst. Oswaldo Cruz ; 108(1): 77-83, Feb. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-666048

RESUMO

The presence of enteric viruses in biosolids can be underestimated due to the inefficient methods (mainly molecular methods) used to recover the viruses from these matrices. Therefore, the goal of this study was to evaluate the different methods used to recover adenoviruses (AdV), rotavirus species A (RVA), norovirus genogroup II (NoV GII) and the hepatitis A virus (HAV) from biosolid samples at a large urban wastewater treatment plant in Brazil after they had been treated by mesophilic anaerobic digestion. Quantitative polymerase chain reaction (PCR) was used for spiking experiments to compare the detection limits of feasible methods, such as beef extract elution and ultracentrifugation. Tests were performed to detect the inhibition levels and the bacteriophage PP7 was used as an internal control. The results showed that the inhibitors affected the efficiency of the PCR reaction and that beef extract elution is a suitable method for detecting enteric viruses, mainly AdV from biosolid samples. All of the viral groups were detected in the biosolid samples: AdV (90%), RVA, NoV GII (45%) and HAV (18%), indicating the viruses' resistance to the anaerobic treatment process. This is the first study in Brazil to detect the presence of RVA, AdV, NoV GII and HAV in anaerobically digested sludge, highlighting the importance of adequate waste management.


Assuntos
Adenoviridae/isolamento & purificação , Vírus da Hepatite A/isolamento & purificação , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Esgotos/virologia , Microbiologia da Água , Anaerobiose , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
9.
Braz. j. biol ; 72(4): 839-846, Nov. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-660379

RESUMO

In order to verify the microbial quality of the influents and effluents of one STP from southern Brazil, an eight-month survey was conducted to examine the presence of total and fecal coliforms and of adenovirus (HAdV), enterovirus (EV), genogroup A rotaviruses (GARV) and Torque teno virus (TTV), in treated effluent samples from São João/Navegantes STP, Porto Alegre (Brazil). A total of 16 samples were collected, eight of influent (raw sewage, prior to treatment), and the other eight of the effluent (post-treatment sewage). Total and fecal coliform levels ranging from 3.6 × 10(4) to 4.4 × 10(7) MPN/100 mL and 2.9 × 10³ to 1.7 × 10(7) MPN/100 mL, were detected in all samples. In raw sewage, HAdV (25%) and GARV (28.6%) viral genomes were detected. The analysis of effluent samples revealed the presence of HAdV (50%), EV (37.5%), and TTV (12.5%) genomic fragments. All samples, regardless of the month analysed, presented detection of a least one virus genus, except for in April. Higher virus detection rates were observed in treated sewage samples (62.5%), and in 80% of them (effluent positive samples) HAdV was detected. Results showed that improvements in sewage monitoring and treatment processes are necessary to reduce the viral and bacterial load on the environment in southern Brazil. To the knowledge of the authors, this is the first study showing the monitoring of viral genomes in influent and effluent samples from a STP located in Porto Alegre (Rio Grande do Sul, Brazil), southern Brazil.


Com o intuito de verificar a qualidade microbiológica de afluentes e efluentes de uma estação de tratamento de esgoto (ETE), um monitoramento de oito meses foi realizado para examinar a presença de coliformes totais e fecais, e de adenovírus (HAdV), enterovírus (EV), rotavírus do genogrupo A (GARV) e torque teno vírus (TTV), em amostras de esgoto tratado da ETE São João/Navegantes, em Porto Alegre-RS, Brasil. Um total de 16 amostras foi coletado, sendo oito de afluente (esgoto bruto, anterior ao tratamento) e oito de efluente (esgoto tratado). Os níveis de coliformes totais e fecais variaram entre 3,6 × 10(4) e 4,4 × 10(7) MPN/100 mL e 2,9 × 10³ e 1,7 × 10(7) MPN/100 mL, respectivamente, tendo sido estes detectados em todas as amostras. No esgoto bruto, foram detectados os genomas virais de HAdV (25%) e GARV (28,6%). A análise das amostras de efluente revelou a presença de fragmentos genômicos de HAdV (50%), EV (37,5%) e TTV (12,5%). Todas as amostras, independentemente do mês analisado, possibilitaram a detecção de pelo menos um gênero viral, exceto no mês de abril. Altas taxas de detecção viral foram observadas em amostras de esgoto tratado (62,5%), sendo que o HAdV foi detectado em 80% dessas amostras de efluente positivas. Os resultados mostram que aprimoramentos no processo de tratamento e monitoramento do esgoto são necessários para reduzir a carga viral e bacteriológica no ambiente do Sul do Brasil. Ao conhecimento dos autores, este é o primeiro estudo de monitoramento de genomas virais em amostras de afluente e efluente de uma ETE localizada em Porto Alegre-Rio Grande do Sul, Brasil.


Assuntos
Vírus de DNA/classificação , Vírus de RNA/classificação , Esgotos/virologia , Microbiologia da Água , Adenoviridae/isolamento & purificação , Brasil , Vírus de DNA/isolamento & purificação , DNA Viral , Enterovirus/isolamento & purificação , Reação em Cadeia da Polimerase , Vírus de RNA/isolamento & purificação , Rotavirus/isolamento & purificação , Torque teno virus/isolamento & purificação , Eliminação de Resíduos Líquidos , Purificação da Água
10.
Mem. Inst. Oswaldo Cruz ; 104(4): 576-579, July 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-523722

RESUMO

The aim of this study was to compare two nucleic acid extraction methods for the recovery of enteric viruses from activated sludge. Test samples were inoculated with human adenovirus (AdV), hepatitis A virus (HAV), poliovirus (PV) and rotavirus (RV) and were then processed by an adsorption-elution-precipitation method. Two extraction methods were used: an organic solvent-based method and a silica method. The organic-based method was able to recoup 20 percent of the AdV, 90 percent of the RV and 100 percent of both the PV and HAV from seeded samples. The silica method was able to recoup 1.8 percent of the AdV and 90 percent of the RV. These results indicate that the organic-based method is more suitable for detecting viruses in sewage sludge.


Assuntos
Adenovírus Humanos/isolamento & purificação , Vírus de RNA/isolamento & purificação , Esgotos/virologia , Microbiologia da Água , DNA Viral/isolamento & purificação , Vírus da Hepatite A/isolamento & purificação , Poliovirus/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Viral/isolamento & purificação , Rotavirus/isolamento & purificação
11.
Iranian Journal of Public Health. 2009; 38 (3): 90-96
em Inglês | IMEMR | ID: emr-101224

RESUMO

Generally, sewage exposed water could be potentially contaminated with enteroviruses. For this reason, enterovirus isolation from sewage specimens is one of the most sensitive indicators for virus circulation in the population. We evaluated the ICC-RT-PCR and cell culture methods for detection of enteroviruses in Tehran sewage system. This research utilized 63 specimens provided through Grab sample method to concentrate by two-phase method and cultured in RD and HEp-2 cells, respectively. All specimens then were inoculated using sensitive cell cultures of RD and HEp-2. After 24 hours incubation at 36[degree sign] by means of Pan E.V primers and afterwards Pan P.V Primers along with specific sabin primers, RT-PCR was carried out on the cell culture specimens. Data were analyzed using SPSS Software [SPSS for and ANOVA test as well as Chi-square test. Out of 63 collected specimens, enteroviruses were isolated from 33 specimens [52.38%] and 41[65.01%] specimens which utilized cell-culture and ICC-RT-PCR methods respectively. Polioviruses were also isolated from 6 specimens. Statistical analysis indicated that there was a significant relationship [0.05 level] between cell culture and ICC-RT-PCR methods to isolate enteroviruses. Further the sensitivity of ICC-RT-PCR method to detect enteroviruses less than 0.01 TCID 50 was evaluated, which indicated that this method is acceptable and sensitive enough to detect enteroviruses in sewage


Assuntos
Esgotos/virologia , Reação em Cadeia da Polimerase/métodos , Técnicas de Cultura de Células , Adenoviridae/isolamento & purificação , Água Doce/virologia , Controle de Qualidade , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Mem. Inst. Oswaldo Cruz ; 103(8): 819-823, Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-502303

RESUMO

The objective of this study was to evaluate the prevalence and dissemination of human astroviruses (HAstV) in the environment by analyzing urban sewage samples from a wastewater treatment plant in the city of Rio de Janeiro, Brazil. A one-year study was performed with a total of 48 raw and treated sewage composite samples, which were collected biweekly from an activated sludge plant. Virus particles were concentrated by the adsorption-elution method using negatively charged membranes associated to a Centriprep Concentrator® 50 (Nihon Millipore). HAstV were detected in 16.7 percent of the samples in raw and treated sewage by using both qualitative and quantitative reverse transcriptase-polymerase chain reactions (RT-PCR and qPCR, respectively). Positive untreated sewage sample exhibited mean values of 1.1 x 10(4) gEq/mL. The qPCR sensitivity was 18 gEq/reaction. Through utilization of qPCR, a HAstV recovery efficiency of 4.2 percent and 4.3 percent was demonstrated for raw and treated sewage samples, respectively. The presence of HAstV in both the raw and treated sewage samples demonstrated the dissemination of these viruses in the environment as well as viral permanence after sewage treatment. There was a reduction in the total and faecal coliform levels, indicating efficiency of the wastewater treatment plant.


Assuntos
Humanos , Mamastrovirus/isolamento & purificação , Esgotos/virologia , Microbiologia da Água , Purificação da Água , Brasil , Monitoramento Ambiental , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Viral/análise , População Urbana
13.
Rev. salud pública ; 8(supl.1): 13-23, mayo 2006. tab
Artigo em Espanhol | LILACS | ID: lil-433510

RESUMO

OBJETIVOS: Implementar un método para la vigilancia ambiental de poliovirus circulante a partir de aguas residuales. MÉTODOS: Se colectaron 6 muestras de aguas residuales en los sitios finales de descarga del acueducto de Armenia, Quindío. Los virus fueron concentrados y extraídos por un método que usa el polietilenglicol y cloruro de sodio como agentes concentradores. La identificación de poliovirus se realizó mediante la técnica de reacción en cadena de la polimerasa empleando cebadores específicos de grupo, de serotipo y de cepa vacunal sabin. RESULTADOS: Se demostró la eficiencia de los métodos de detección viral empleados. Se encontró la presencia de poliovirus en 5 de las 6 (83 %) muestras colectadas. La identificación serotipo-específica reveló la presencia de poliovirus tipo 1 y 3 en las muestras estudiadas. Todos los poliovirus detectados resultaron ser del tipo vacunal lo cual aporta una evidencia más a favor de la no circulación de poliovirus salvaje en la región. CONCLUSIÓN El sistema de vigilancia a partir de aguas residuales puede ser una herramienta sensible para la detección de la circulación de poliovirus.


Assuntos
Poliovirus/isolamento & purificação , Esgotos/virologia , Colômbia , Microbiologia Ambiental , Vacina Antipólio Oral , Poliovirus/classificação , Polietilenoglicóis , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Cloreto de Sódio , Virologia/métodos
14.
Egyptian Journal of Microbiology. 2005; 40: 81-93
em Inglês | IMEMR | ID: emr-70421

RESUMO

This study was carried out to assess the sludge treatment processes applied at the 6[th] October wastewater treatment plant [WWTP], Giza, Egypt. The applied processes included aerobic digestion followed by gravity thickening, filter-pressing and drying beds [in emergency cases]. Bacteriological, virological and parasitological evaluation was carried out. Results showed that aerobic digestion removed two log units of total and faecal coliforms and one log unit of Escherichia coli [E. coli] and feacal streptococci. The removal percentages of coliphage and enteroviruses after aerobic digestion were 97.0 and 58.3%, resectively. The salmonellae disappeared from sludge after aerobic digestion. Qualitative and quantitative decrease in helminth ova [Ascaris, Trichuris, Trichostrongylus, Taenia and Hymenoleois] was observed after aerobic digestion and thickening stages. An average decreae of 4 log units for total and faecal coliforms, 3 log units for each of faecal streptococci and coliphage and 2 log units for E. coli through sludge treatment process was observed. Enteroviruses, helminth ova and enteric protozoa were completely eliminated from sludge after 6 months in drying beds. The loads of faecal coliform, E coli, faecal streptococci and coliphage in the dried sludge were 6.5 x 10[2], 1.6 x10[2], 4.5 x 10[2], 4.56 x 10[2] cfu and 8.5 x 10[1] pfu/g, respectively. Microbiological quality of the final treated sludge complied with the regulations of Untied States Environmental Protection Agency


Assuntos
Gerenciamento de Resíduos , Poluição da Água , Esgotos/parasitologia , Esgotos/virologia , Escherichia coli , Streptococcus , Salmonella , Ascaris , Trichuris , Tricostrongilose , Teníase , Colífagos
15.
Mem. Inst. Oswaldo Cruz ; 96(6): 815-821, Aug. 2001. tab
Artigo em Inglês | LILACS | ID: lil-298608

RESUMO

A modified adsorption-elution method for the concentration of seeded rotavirus from water samples was used to determine various factors which affected the virus recovery. An enzyme-linked immunosorbent assay was used to detect the rotavirus antigen after concentration. Of the various eluents compared, 0.05M glycine, pH 11.5 gave the highest rotavirus antigen recovery using negatively charged membrane filtration whereas 2.9 percent tryptose phosphate broth containing 6 percent glycine; pH 9.0 was found to give the greatest elution efficiency when a positively charged membrane was used. Reconcentration of water samples by a speedVac concentrator showed significantly higher rotavirus recovery than polyethylene glycol precipitation through both negatively and positively charged filters (p-value <0.001). In addition, speedVac concentration using negatively charged filtration resulted in greater rotavirus recovery than that using positively charged filtration (p-value = 0.004). Thirty eight environmental water samples were collected from river, domestic sewage, canals receiving raw sewage drains, and tap water collected in containers for domestic use, all from congested areas of Bangkok. In addition, several samples of commercial drinking water were analyzed. All samples were concentrated and examined for rotavirus antigen. Coliforms and fecal coliforms (0->1,800 MPN/100 ml) were observed but rotavirus was not detected in any sample. This study suggests that the speedVac reconcentration method gives the most efficient rotavirus recovery from water samples


Assuntos
Rotavirus/isolamento & purificação , Microbiologia da Água , Análise de Variância , Antígenos Virais/análise , Ensaio de Imunoadsorção Enzimática , Sensibilidade e Especificidade , Esgotos/virologia
16.
Mem. Inst. Oswaldo Cruz ; 95(5): 713-6, Sept.-Oct. 2000. tab, ilus
Artigo em Inglês | LILACS | ID: lil-267900

RESUMO

Zeta plus filter membranes (ZP60S) have been shown to be efficient for rotavirus concentration from wastewater and for the reduction of cytotoxicity for cell cultures. Recently a variability in both properties was observed. In view of the low costs and the high virus recovery rates obtained in the past, we re-evaluated the application of ZP60S filter membranes for virus concentration from environmental samples. Some factors that could interfere with the concentration strategy using ZP60S were also considered and assessed including the type of water to be filtered and the possible release of toxic substances from the membrane matrix during filtration.


Assuntos
Membranas Artificiais , Rotavirus/isolamento & purificação , Esgotos/virologia , Microbiologia da Água , Técnicas de Cultura de Células , Citotoxinas , Filtração/métodos , Esgotos/química
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