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Parasitological risk assessment from wastewater reuse for disposal in soil in developing countries

Cutolo, Silvana Audrá; Piveli, Roque Passos; Santos, Jeferson G.; Montes, Celia Regina; Sundefeld, Gilberto; Campos, Fabio; Gomes, Tamara M.; Melfi, Adolpho Jose
Fonte: IWA PUBLISHING; LONDON Publicador: IWA PUBLISHING; LONDON
Tipo: Artigo de Revista Científica
Português
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36.78%
The purpose of this work is to analyze the parasitological risks of treated wastewater reuse from a stabilization pond in the city of Piracicaba, in the State of Sao Paulo (Brazil), and the level of treatment required to protect public health. Samples were taken from raw and treated wastewater in stabilization ponds and submitted to a parasitological, microbiological and physicochemical analysis. The study revealed on treated wastewater the presence of Ascaris sp. and Entamoeba coli with an average density of 1 cysts L-1 and 6 eggs L-1, respectively. For Ascaris, the annual risks of infection due to the accidental ingestion of wastewater irrigation were 7.5 x 10(-2) in 208 days and 8.7 x 10(-2) in 240 days. For Total Coliforms and Escherichia coli in treated wastewater, the average density was 1.0 x 10(5) MPN/100 ml and 2.7 x 10(4) MPN/100 ml respectively, representing 99% and 94% removal efficiency, respectively. For BOD, COD, TS and TSS removal efficiency was 69, 80, 50 and 71%, respectively. The removal efficiency for nitrogen; ammonia nitrogen and total phosphate was 24, 19 and 68%, respectively. The average density of helminths eggs in treated wastewater is higher compared to the density of the limit value of <= 1 egg L-1 and tolerable risk is above the level recommended by the World Health Organization. Multiple barriers are necessary for the reduction of organic matter...

Propriedades imunorreguladoras de extratos solúveis obtidos de vermes adultos ou de ovos de Ascaris suum.; Immunoregulatory properties of soluble extracts from Ascaris suum worms or eggs.

Souza, Valdênia Maria Oliveira de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 20/10/1999 Português
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36.97%
O extrato de Ascaris suum (Asc total), preparado a partir de uma mistura de vermes machos e fêmeas (albergando ovos), suprime a resposta imune específica a ovalbumina (OA). A partir do fracionamento deste extrato por gel filtração demonstrou-se que componentes protéicos de alto peso molecular (PM), eluídos no primeiro pico (PI), eram supressores da resposta a OA e os eluídos no terceiro pico (PIII) estimularam uma resposta maior de anticorpos IgE anti-Asc. Uma resposta do tipo Th2 foi preferencialmente estimulada por este extrato, sendo as citocinas IL-4 e IL-10 atuantes na supressão dos parâmetros da resposta anti-OA mediados por células Th1. Em algumas espécies de helmintos a resposta Th2 é estimulada de forma estágio-específica. Assim, analisamos neste trabalho quais dos componentes do Asc total seriam responsáveis pelo efeito supressor. Verificamos que os extratos dos vermes adultos apresentaram perfis cromatográficos semelhantes ao do extrato total. O perfil cromatográfico do Asc O foi distinto, com um segundo pico (PII) mais evidente e apresentou um quarto pico de menor PM. O fracionamento eletroforético confirmou uma concentração de proteínas com PM entre 107 e 52 kDa e a presença de proteínas adicionais entre 27...

Inativação térmica de ovos de helmintos em água e em biossólidos digeridos: cinética em reator batelada e modelagem matemática em reator tubular.; Kinetics of helminth eggs inactivation in water and digested sludges by saturated steam produced with methane from anaerobic digestors.

Simoneti, Marilza de Fátima
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/11/2006 Português
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47.15%
O biossólido pode ser um valioso recurso ao ser utilizado em solos agrícolas; porém, um dos principais problemas de sua utilização é a presença de patógenos que podem disseminar doenças. Os principais patógenos presentes no biossólido são vírus, bactérias, protozoários e helmintos. Dentre os patógenos existentes no biossólido, os ovos de helmintos são os mais resistentes à inativação térmica e, para helmintos, os ovos de Ascaris são utilizados como indicador desses parasitas devido à comum ocorrência e resistência térmica. Dentre os processos efetivos existentes para inativar patógenos do biossólido - compostagem, secagem e tratamento térmico, digestão aeróbia termofílica, irradiação com raios beta e gama e pasteurização - este último, utilizando como fonte de calor o vapor saturado gerado a partir da queima do metano produzido em digestores anaeróbios de ETEs convencionais, é um processo de tecnologia simples, com baixo custo de implantação e operação e necessita de pequena área para implantação, sendo indicado para grandes metrópoles de países em desenvolvimento. A inativação térmica de helmintos do biossólido é o objetivo deste projeto de pesquisa. São estudadas as cinéticas de inativação térmica de ovos de Ascaris suum em água e em biossólido digerido...

Remoção de ovos de helmintos de esgotos secundários, por meio de filtros rápidos de areia, carvão antracitoso e zeólito para reúso agrícola e urbano não potável.; Removal of helminth eggs in sewage side, through rapid sand filters, anthracite coal and zeolite for agricultural reuse and urban non-potable.

Gobbi, Sidinei Antonio
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 22/02/2010 Português
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37.02%
A presença de ovos de helmintos é um dos principais problemas do reúso de esgotos tratados na irrigação agrícola e no reúso urbano não potável. Isso porque pode haver contaminação dos trabalhadores que manipulam a água de reúso e da população consumidora. Os ovos de helmintos não são removidos com eficiência por meio de operações e processos unitários convencionais. Esses processos não possibilitam a remoção de ovos de helmintos a níveis estabelecidos pelas diretrizes da Organização Mundial da Saúde (OMS) para o reúso. Avaliar a filtração até a gravidade, como unidade complementar de tratamento, para a remoção de ovos de helmintos é o objetivo desta pesquisa. Como os efluentes de estações de tratamento de esgotos locais apresentam concentrações muito variáveis de ovos de helmintos, foi utilizada uma solução sintética de ovos padronizados Ascaris suum. A solução sintética preparada com o uso dos ovos padronizados foi usada na determinação dos parâmetros de operação do processo de filtração. Após esses ensaios, foram realizados testes em escala piloto com esgoto tratado, objetivando o estudo da influência da matéria orgânica, dos sólidos e de outros interferentes do processo. Os experimentos com solução sintética foram desenvolvidos nos laboratórios do Centro Internacional de Referência em Reúso de Água (CIRRA)...

Detecção e quantificação de ovos viáveis de Ascaris sp e outros ovos de helmintos em lodo de esgoto; Detection and quantification of Ascaris sp and other helminth eggs in sewage sludge.

Bastos, Veridiana Karmann
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 08/02/2012 Português
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37.21%
Introdução O lodo gerado em estações de tratamento de esgotos é um resíduo de composição variável e com potencial poluidor dependendo de sua origem, tipo de tratamento e sazonalidade; pode conter patógenos dentre os quais os parasitas. Porém, quando tratado adequadamente, o lodo de esgoto pode ser aplicado na agricultura como fertilizante ou condicionador de solo. Em países em desenvolvimento, estudos têm demonstrado que a incidência de enteroparasitoses é elevada, sendo Ascaris sp um dos mais prevalentes. Portanto, o uso agrícola do lodo de esgoto pode oferecer riscos à saúde humana. Com intuito de salvaguardar a saúde da população entrou em vigor a Resolução CONAMA nº375/06, que estabelece critérios e procedimentos para o uso do lodo em áreas agrícolas. Objetivo - Determinar e quantificar ovos de helmintos e de Ascaris sp em lodos provenientes de três ETEs de uma região metropolitana, verificando o atendimento ao padrão parasitológico estabelecido pela CONAMA nº375/06. Método Utilizou-se o método descrito no apêndice I da norma CFR 503 USEPA de 2003. Resultados Os lodos analisados no período do estudo apresentaram rica fauna parasitária onde foram observados ovos de Ancylostoma sp, Ascaris sp...

Liver abscess caused by Ascaris lumbricoides: case report

PINILLA,Análida Elizabeth; LÓPEZ,Myriam Consuelo; RICAURTE,Orlando; CASTILLO,Blanca; MURCIA,Martha Isabel; NICHOLLS,Rubén Santiago; DUQUE,Sofía; OROZCO,Luis Carlos
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2001 Português
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A case is reported of a woman who lived in a rural area with a chronic illness that consisted of weight loss and abdominal pain in the epigastrium and upper right quadrant. The initial diagnosis was a mass in the liver, which was later, demonstrated, both by direct and histological examination, to be an abscess caused by Ascaris lumbricoides. Eggs of Ascaris lumbricoides and abundant Charcot-Leyden Crystals were found.

Environmental contamination by Toxocara sp eggs in public areas of Salvador, Bahia state, Brazil

Alcântara,Neuza; Bavia,Emilia; Silvão,Rose Mary; Carvalho,Elza
Fonte: Sociedade Brasileira de Medicina Tropical - SBMT Publicador: Sociedade Brasileira de Medicina Tropical - SBMT
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/1989 Português
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36.65%
A survey ofparasite eggs and cysts in soil and dog feces collected in public places of 23 boroughs of Salvador, a city in the Northeast of Brazil, was performed. High degree of contamination by Toxocara sp eggs was observed in all boroughs studied; other parasites found included: Ascaris lumbricoides, hookworms, whipworms and protozoan cysts. Parks andpublic gardens were more contaminated than streets and beachesfor all parasites, including Toxocara sp.

In vitro study on thiabendazole action on viability of Ascaris lumbricoides (Lineu, 1758) eggs

Massara,Cristiano Lara; Ferreira,Rafaela Salgado; Guerra,Henrique Leonardo; Carvalho,Omar dos Santos
Fonte: Sociedade Brasileira de Medicina Tropical - SBMT Publicador: Sociedade Brasileira de Medicina Tropical - SBMT
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2001 Português
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36.88%
The in vitro activity of thiabendazole on Ascaris lumbricoides eggs, which were recovered from uteri of worm excreted after chemotherapeutic treatment, was studied. Four concentrations of the drug were used: 1 -- 2.5 -- 5 -- and 10 ppm during 24, 48 and 72 hours of exposure. Subsequently, the eggs were centrifuged, washed three times and H2SO4 0.1N was added. The eggs were maintained in an incubator for 20 days at 28°C. Finally, the percentage of embryonated eggs was determined under a lightmicroscope at a 100X magnification. After 48 and 72 hours of thiabendazole exposure, at a concentration of 10ppm, the drug showed complete inhibition of egg embryonation.

Development of Ascaris lumbricoides eggs from females eliminated after chemotherapy in man

Carvalho,Omar S.; Guerra,H. L.; Massara,C. L.
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/1992 Português
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36.92%
The development of Ascaris lumbricoides eggs obtained from females eliminated after treatment of infected individuals with a single oral dose of the antihelminthic drugs thiabendazole (50 mg/kg - 33 patients) or levamisole (250 mg - independent of body weigth - 20 patients) was studied. Every female eliminated up to 72 h after treatment were dissected, the uterus isolated and sectioned into small fragments. The eggs were transferred to plastics tubes and incubated at 28 degrees centigrades in 0.1 N H2 SO4 for 100 days. Every 20 days, starting from the 20 th up to the 100 th day, the extent of egg embryonation ratio was determined. The culture of A. lumbricoides eggs obtained from females from patients treated with thiabendazole did not contain embryonated eggs until the final period of observation. In contrast, the eggs obtained from females eliminated by patients treated with levamisole (control) presented an embryonation rate of 0.0 - 98.0% in the same period.

Molecular paleoparasitological diagnosis of Ascaris sp. from coprolites: new scenery of ascariasis in pre-Colombian South America times

Leles,Daniela; Araújo,Adauto; Ferreira,Luiz Fernando; Vicente,Ana Carolina Paulo; Iñiguez,Alena Mayo
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2008 Português
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46.67%
Paleoparasitological studies using microscopy showed that Ascarisand Trichuris trichiura are the human intestinal parasites most found in archaeological sites. However, in pre-Columbian South American archaeological sites, Ascaris is rare. In this work we standardized a molecular methodology for Ascaris diagnosis directly from ancient DNA retrieved from coprolites. Using cythochrome b gene (142 bp) target, ancient DNA sequences were retrieved from South American samples, negative by microscopy. Moreover, the methodology applied was sensitive enough to detect ancient DNA extracted from 30 Ascaris eggs from an European coprolite. These results revealed a new scenery for the paleodistribution of Ascaris in South America.

Molecular paleoparasitological diagnosis of Ascaris sp. from coprolites: new scenery of ascariasis in pre-Colombian South America times

Leles,Daniela; Araújo,Adauto; Ferreira,Luiz Fernando; Vicente,Ana Carolina Paulo; Iñiguez,Alena Mayo
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2008 Português
Relevância na Pesquisa
46.67%
Paleoparasitological studies using microscopy showed that Ascarisand Trichuris trichiura are the human intestinal parasites most found in archaeological sites. However, in pre-Columbian South American archaeological sites, Ascaris is rare. In this work we standardized a molecular methodology for Ascaris diagnosis directly from ancient DNA retrieved from coprolites. Using cythochrome b gene (142 bp) target, ancient DNA sequences were retrieved from South American samples, negative by microscopy. Moreover, the methodology applied was sensitive enough to detect ancient DNA extracted from 30 Ascaris eggs from an European coprolite. These results revealed a new scenery for the paleodistribution of Ascaris in South America.

Paleoparasitological report on Ascaris aDNA from an ancient East Asian sample

Oh,Chang Seok; Seo,Min; Lim,Nam Jin; Lee,Sang Jun; Lee,Eun-Joo; Lee,Soong Deok; Shin,Dong Hoon
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2010 Português
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46.67%
In this study, Ascaris DNA was extracted and sequenced from a medieval archaeological sample in Korea. While Ascaris eggs were confirmed to be of human origin by archaeological evidence, it was not possible to pinpoint the exact species due to close genetic relationships among them. Despite this shortcoming, this is the first Ascaris ancient DNA (aDNA) report from a medieval Asian country and thus will expand the scope of Ascaris aDNA research.

Extracts of Ascaris suum egg and adult worm share similar immunosuppressive properties

Souza,V.M.O.; Faquim-Mauro,E.L.; Macedo,M.S.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2002 Português
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Adult Ascaris suum body extract (Asc) prepared from male and female worms (with stored eggs) down-regulates the specific immune response of DBA/2 mice to ovalbumin (OA) and preferentially stimulates a Th2 response to its own components, which is responsible for the suppression of the OA-specific Th1 response. Here, we investigated the participation of soluble extracts prepared from male or female worms or from eggs (E-Asc) in these immunological events. Extracts from either sex (1 mg/animal) or E-Asc (0.35 or 1 mg protein/animal) suppressed the delayed-type hypersensitivity (DTH) reaction (60-85%), proliferative response (50-70%), IL-2 and IFN-gamma secretion (below detection threshold) and IgG1 antibody production (70-90%) of DBA/2 mice to OA. A dose of 0.1 mg E-Asc/animal did not change DTH or proliferation, but was as effective as 0.35 mg in suppressing IL-2 and IFN-gamma, and OA-specific IgG1 antibodies. Lymph node cells from DBA/2 mice injected with Asc (1 mg/animal) or a high dose of E-Asc (1 mg protein/animal) secreted IL-4 upon in vitro stimulation with concanavalin A. As previously demonstrated for Asc, the cytokine profile obtained with the E-Asc was dose dependent and changed towards Th1 when a low dose (0.1 mg protein/animal) was used. Taken together...

Inactivation of Viable Ascaris Eggs by Reagents during Enumeration

Nelson, Kara L.; Darby, Jeannie L.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /12/2001 Português
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47.12%
Various reagents commonly used to enumerate viable helminth eggs from wastewater and sludge were evaluated for their potential to inactivate Ascaris eggs under typical laboratory conditions. Two methods were used to enumerate indigenous Ascaris eggs from sludge samples. All steps in the methods were the same except that in method I a phase extraction step with acid-alcohol (35% ethanol in 0.1 N H2SO4) and diethyl ether was used whereas in method II the extraction step was avoided by pouring the sample through a 38-?m-mesh stainless steel sieve that retained the eggs. The concentration of eggs and their viability were lower in the samples processed by method I than in the samples processed by method II by an average of 48 and 70%, respectively. A second set of experiments was performed using pure solutions of Ascaris suum eggs to elucidate the effect of the individual reagents and relevant combination of reagents on the eggs. The percentages of viable eggs in samples treated with acid-alcohol alone and in combination with diethyl ether or ethyl acetate were 52, 27, and 4%, respectively, whereas in the rest of the samples the viability was about 80%. Neither the acid nor the diethyl ether alone caused any decrease in egg viability. Thus...

Inactivation of Single-Celled Ascaris suum Eggs by Low-Pressure UV Radiation

Brownell, Sarah A.; Nelson, Kara L.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /03/2006 Português
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37.03%
Intact and decorticated single-celled Ascaris suum eggs were exposed to UV radiation from low-pressure, germicidal lamps at fluences (doses) ranging from 0 to 8,000 J/m2 for intact eggs and from 0 to 500 J/m2 for decorticated eggs. With a UV fluence of 500 J/m2, 0.44- ± 0.20-log inactivation (mean ± 95% confidence interval) (63.7%) of intact eggs was observed, while a fluence of 4,000 J/m2 resulted in 2.23- ± 0.49-log inactivation (99.4%). (The maximum quantifiable inactivation was 2.5 log units.) Thus, according to the methods used here, Ascaris eggs are the most UV-resistant water-related pathogen identified to date. For the range of fluences recommended for disinfecting drinking water and wastewater (200 to 2,000 J/m2), from 0- to 1.5-log inactivation can be expected, although at typical fluences (less than 1,000 J/m2), the inactivation may be less than 1 log. When the eggs were decorticated (the outer egg shell layers were removed with sodium hypochlorite, leaving only the lipoprotein ascaroside layer) before exposure to UV, 1.80- ± 0.32-log reduction (98.4%) was achieved with a fluence of 500 J/m2, suggesting that the outer eggshell layers protected A. suum eggs from inactivation by UV radiation. This protection may have been due to UV absorption by proteins in the outer layers of the 3- to 4-?m-thick eggshell. Stirring alone (without UV exposure) also inactivated some of the Ascaris eggs (?20% after 75 min)...

A Real-Time PCR Method for Quantifying Viable Ascaris Eggs Using the First Internally Transcribed Spacer Region of Ribosomal DNA?

Pecson, Brian M.; Barrios, José Antonio; Johnson, David R.; Nelson, Kara L.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Português
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47.13%
Worldwide, 1.4 billion people are infected with the intestinal worm Ascaris lumbricoides. As a result, Ascaris eggs are commonly found in wastewater and sludges. The current microscopy method for detecting viable Ascaris eggs is time- and labor-intensive. The goal of this study was to develop a real-time quantitative PCR (qPCR) method to determine the levels of total and viable Ascaris eggs in laboratory solutions using the first internally transcribed spacer (ITS-1) region of ribosomal DNA (rDNA) and rRNA. ITS-1 rDNA levels were proportional to Ascaris egg cell numbers, increasing as eggs developed from single cells to mature larvae and ultimately reaching a constant level per egg. Treatments causing >99% inactivation (high heat, moderate heat, ammonia, and UV) eliminated this increase in ITS-1 rDNA levels and caused decreases that were dependent on the treatment type. By taking advantage of this difference in ITS-1 rDNA level between viable, larvated eggs and inactivated, single-celled eggs, qPCR results were used to develop inactivation profiles for the different treatments. No statistical difference from the standard microscopy method was found in 75% of the samples (12 of 16). ITS-1 rRNA was detected only in samples containing viable eggs...

Inactivation of Ascaris Eggs in Source-Separated Urine and Feces by Ammonia at Ambient Temperatures?

Nordin, Annika; Nyberg, Karin; Vinnerås, Björn
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: text
Português
Relevância na Pesquisa
36.75%
Sustainable management of toilet waste must prevent disease transmission but allow reuse of plant nutrients. Inactivation of uterus-derived Ascaris suum eggs was studied in relation to ammonia in source-separated urine without additives and in human feces to which urea had been added, in order to evaluate ammonia-based sanitation for production of safe fertilizers from human excreta. Urine was used concentrated or diluted 1:1 and 1:3 with tap water at 4, 14, 24, and 34°C. Fecal material, with and without ash, was treated with 1% or 2% (wt/wt) urea at 24 and 34°C. At 34°C eggs were inactivated in less than 10 days in urine and in amended feces. At 24°C only feces with 2% (wt/wt) urea or 1% (wt/wt) urea at high pH (10) inactivated all eggs within 1 month, and no inactivation was observed after 75 days in urine diluted 1:3 (18 ± 11 mM NH3). At temperatures of ?24°C, NH3 proved to be an efficient sanitizing agent in urine and feces at concentrations of ?60 mM. Treating fecal material at 34°C can give a 6-log10 egg inactivation within 1 month, whereas at 24°C 6 months of treatment is necessary for the same level of egg inactivation. At temperatures of 14°C and below, inactivation rates were low, with viable eggs after 6 months even in concentrated urine.

A Quantitative Assessment Method for Ascaris Eggs on Hands

Jeandron, Aurelie; Ensink, Jeroen H. J.; Thamsborg, Stig M.; Dalsgaard, Anders; Sengupta, Mita E.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: text
Publicado em 06/05/2014 Português
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47.06%
The importance of hands in the transmission of soil transmitted helminths, especially Ascaris and Trichuris infections, is under-researched. This is partly because of the absence of a reliable method to quantify the number of eggs on hands. Therefore, the aim of this study was to develop a method to assess the number of Ascaris eggs on hands and determine the egg recovery rate of the method. Under laboratory conditions, hands were seeded with a known number of Ascaris eggs, air dried and washed in a plastic bag retaining the washing water, in order to determine recovery rates of eggs for four different detergents (cationic [benzethonium chloride 0.1% and cetylpyridinium chloride CPC 0.1%], anionic [7X 1% - quadrafos, glycol ether, and dioctyl sulfoccinate sodium salt] and non-ionic [Tween80 0.1% -polyethylene glycol sorbitan monooleate]) and two egg detection methods (McMaster technique and FLOTAC). A modified concentration McMaster technique showed the highest egg recovery rate from bags. Two of the four diluted detergents (benzethonium chloride 0.1% and 7X 1%) also showed a higher egg recovery rate and were then compared with de-ionized water for recovery of helminth eggs from hands. The highest recovery rate (95.6%) was achieved with a hand rinse performed with 7X 1%. Washing hands with de-ionized water resulted in an egg recovery rate of 82.7%. This washing method performed with a low concentration of detergent offers potential for quantitative investigation of contamination of hands with Ascaris eggs and of their role in human infection. Follow-up studies are needed that validate the hand washing method under field conditions...

Ancient Mitochondrial DNA Analyses of Ascaris Eggs Discovered in Coprolites from Joseon Tomb

Oh, Chang Seok; Seo, Min; Hong, Jong Ha; Chai, Jong-Yil; Oh, Seung Whan; Park, Jun Bum; Shin, Dong Hoon
Fonte: The Korean Society for Parasitology and Tropical Medicine Publicador: The Korean Society for Parasitology and Tropical Medicine
Tipo: text
Português
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46.82%
Analysis of ancient DNA (aDNA) extracted from Ascaris is very important for understanding the phylogenetic lineage of the parasite species. When aDNAs obtained from a Joseon tomb (SN2-19-1) coprolite in which Ascaris eggs were identified were amplified with primers for cytochrome b (cyt b) and 18S small subunit ribosomal RNA (18S rRNA) gene, the outcome exhibited Ascaris specific amplicon bands. By cloning, sequencing, and analysis of the amplified DNA, we obtained information valuable for comprehending genetic lineage of Ascaris prevalent among pre-modern Joseon peoples.

Ascaris and Escherichia coli Inactivation in an Ecological Sanitation System in Port-au-Prince, Haiti

Berendes, David; Levy, Karen; Knee, Jackie; Handzel, Thomas; Hill, Vincent R.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: text
Publicado em 01/05/2015 Português
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36.58%
The goal of this study was to evaluate the microbial die-off in a latrine waste composting system in Port-au-Prince, Haiti. Temperature data and samples were collected from compost aged 0 – 12+ months. Samples collected from compost bin centers and corners at two depths were assessed for moisture content, E. coli concentration, and Ascaris spp. viability. Center temperatures in compost bins were all above 58 °C, while corner temperatures were 10 – 20 °C lower. Moisture content was 67 ± 10% in all except the oldest compost. A 4-log reduction in E. coli was observed over the first sixteen weeks of composting at both locations and depths, after which E. coli was undetectable (LOD: 142 MPN g-1 dry weight). In new compost, 10.4% and 8.3% of Ascaris eggs were viable and fully embryonated, respectively. Percent viability dropped to zero in samples older than six weeks. These findings indicate that the Haitian EcoSan composting process was effective in inactivating E. coli and Ascaris spp. in latrine waste within sixteen weeks. This study is one of the first to document efficacy of an ecological sanitation system under field conditions and provides insight into composting methods and monitoring for other international settings.