SUMMARYCryptosporidium parvum and Giardia duodenalis are waterborne parasites that have caused several outbreaks of gastrointestinal disease associated with drinking water. Due to the lack of studies about the occurrence of these protozoa in water in the Southeast of Brazil, an investigation was conducted to verify the presence of cysts and oocysts in superficial raw water of the Atibaia River. The water samples were submitted to membrane filtration (3.0 mm) and elution was processed by (1) scraping and rinsing of membrane (RM method) and (2) acetone-dissolution (ADM method). Microbiologic and chemical parameters were analyzed. Aliquots of the pellets were examined by immunofluorescence (Merifluor, Meridian Diagnostics, Cincinnati, Ohio). All water samples were positive for Cryptosporidium and Giardia, in spite of the high turbidity. Higher recovery rates occurred in samples treated by the RM method than by the ADM technique. The goal for future work is the assessment of viability of cysts and oocysts to determine the public health significance of this finding.

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Giardia and Cryptosporidium have caused several outbreaks of gastroenteritis in humans associated with drinking water. Contaminated sewage effluents are recognized as a potential source of waterborne protozoa. Due to the lack of studies about the occurrence of these parasites in sewage samples in Brazil, we compared the efficiency of two procedures for concentrating cysts and oocysts in activated sludge samples of one sewage treatment plant. For this, the samples were submitted to i) concentration by the ether clarification procedure (ECP) and to ii) purification by sucrose flotation method (SFM) and aliquots of the pellets were examined by immunofluorescence. Giardia cysts were present in all samples (100.0%; n = 8) when using ECP and kit 1 reagents, while kit 2 resulted in six positive samples (85.7%; n = 7). As for SFM, cysts were detected in 75.0% and 100.0% of these samples (for kit 1 and 2, respectively). Regarding Cryptosporidium, two samples (25.0%; kit 1 and 28.5% for kit 2) were detected positive by using ECP, while for SFM, only one sample (examined by kit 1) was positive (12.5%). The results of the control trial revealed Giardia and Cryptosporidium recovery efficiency rates for ECP of 54.5% and 9.6%, while SFM was 10.5% and 3.2%, respectively. Considering the high concentration detected, a previous evaluation of the activated sludge before its application in agriculture is recommended and with some improvement, ECP would be an appropriate simple technique for protozoa detection in sewage samples.

Among many waterborne diseases the giardiasis and cryptosporidiosis are of particular public health interest, because Giardia cysts and Cryptosporidium oocysts can persist for long periods in the environment, and both pathogenic protozoa have been implicated as the cause of many outbreaks of gastroenteritis in the last 25 years. In order to evaluate the efficiency of cysts and oocysts' removal by the activated sludge process, and by UV reactor in inactivating cysts and oocysts in one wastewater treatment plant (WWTP) of Campinas, three sampling points were selected for study: (1) influent, (2) treated effluent without UV disinfection and (3) treated effluent with UV disinfection. Giardia spp. cysts prevailed with higher density in the three different sample types. Cryptosporidium spp. oocysts were observed in only two samples of influent and just one sample of treated sewage with UV disinfection. In the animal infectivity assay for Giardia spp, one mouse of the UV treated group revealed trophozoites in intestinal scrapings. The results of the present study indicate that treatment by activated sludge process delivered a reduction of 98.9% of cysts and 99.7% of oocysts and UV disinfection was not completely efficient regarding the inactivation of Giardia cysts in the case of the WWTP studied.

Vários gêneros de cianobactérias produzem metabólitos secundários tóxicos, entre eles as hepatotoxinas microcistinas. A análise de microcistinas em águas para abastecimento humano é uma exigência do Ministério da Saúde (Portaria 518/2004), mas essa portaria ainda não estabelece o método de extração e análise a serem usados e a quantificação da toxina é comumente realizada por ELISA ("enzyme-linked immunosorbent assay") ou HPLC (cromatografia líquida de alta eficiência), cuja eficiência depende do método de extração utilizado. Neste trabalho foi desenvolvido um método simples, rápido e barato de extração para o isolamento e identificação de microcistinas. Para isso, selecionou-se a linhagem Microcystis aeruginosa NPLJ-4 descrita como produtora de microcistina-LR. Oito diferentes tratamentos foram testados para determinar a melhor extração da toxina. As amostras foram analisadas por LC-MS (cromatografia líquida acoplada a espectrometria de massas), ELISA e Q-TOF ("quadrupole time-of-flight"). Os resultados mostraram que a melhor extração foi a que usou sonicação das amostras diluídas em água. O método proposto permite o processamento rápido das amostras e estabelece um método de extração para análise e identificação de microcistina-LR e outras variantes.Several cyanobacterial genera produce toxic secondary metabolites, the most well-known of which are the hepatotoxic microcystins (MCYSTs). Microcystin analyses in drinking water are a requirement of the Health Ministry (Regulation 518/2004) in Brazil, but this regulation does not establish which extraction and analytical method should be used; toxin quantification is usually carried out by ELISA (enzyme-linked immunosorbent assay) or HPLC (high performance liquid chromatography), the efficiency of which depends on the extraction method used. In this work a simple, fast and cheap method of extraction was developed for the isolation and identification of MCYSTs. For this, the strain Microcystis aeruginosa NPLJ-4, reported to be a MCYST-LR producer, was selected. Eight different treatments were tested to determine the best MCYST extraction. Samples were applied in LC-MS (liquid chromatography-mass spectrometry), ELISA and Q-TOF (quadrupole time-of-flight). The most efficient extraction was achieved by sonicating samples diluted in water. The proposed method permits rapid sample processing, and establishes an extraction method for both the analysis and identification of MCYST-LR and other variants.