Controle de qualidade analítica dos métodos utilizados para a detecção de protozoários patogênicos em amostras de água / Control of the analytic quality of the methods used for the detection of pathogenic protozoans in water samples

As espécies de protozoários patogênicos de veiculação hídrica Giardia spp. e Cryptosporidium spp. foram responsáveis por cerca 90% dos surtos de gastroenterite ocorridos nos últimos 25 anos, em vários países. Critérios de avaliação das etapas referentes à detecção destes agentes em amostras de água, tais como: precisão inicial, inoculação nas amostras em água bruta e, diagnóstico e localização de erros estão abordados neste trabalho. Estes critérios devem ser correntemente aplicados e constantemente avaliados pelos laboratórios, a fim de assegurar a confiabilidade dos resultados obtidos durante um monitoramento e, assim, fornecer subsídios para uma avaliação do risco de surtos.

The waterborne pathogenic protozoan species Giardia spp. and Cryptosporidium spp. have been responsible for the majority (90%) of the gastroenteritis outbreaks that have occurred in the last 25 years in various countries. This paper discusses evaluation criteria pertaining to the steps involved in the detection of these microorganisms in water samples, such as: initial precision, inoculation in environmental samples, diagnosis and error localization. These criteria should be often applied and evaluated by laboratories in order to assure the reliability of the results obtained in a program of monitoring, thus aiding in the evaluation of the risks of outbreaks.

Occurrence of cryptosporidial oocysts and giardia cysts in bottled mineral water commercialized in the city of Campinas, state of Säo Paulo, Brazil

The consumption of bottled mineral water has significantly increased in Brazil so that it is in the interest of public health to determine the parasitological and microbiological status of some brands of Brazilian mineral water available in the town of Campinas, Säo Paulo, Brazil. For this purpose, detection of protozoa by direct immunofluorescence technique and microbiological parameters were determined for each specimen after membrane filtration. Giardia cysts were not present while cryptosporidial oocysts were detected in two samples. The counts of protozoa varied from 0.2 to 0.5 oocysts/l. The detected level of Pseudomonas aeruginosa and heterotrophic bacteria reflected the level of organic enrichment of the water