Detection of Giardia and Cryptosporidium cysts/oocysts in watersheds and drinking water sources in Brazil urban areas

Abstract

The protozoan parasites Giardia and Cryptosporidium have been described as important waterborne disease pathogens, and are associated with severe gastrointestinal illnesses.The objective of this paper was to investigate the presence of Giardia cysts and Cryptosporidium oocysts in samples from watershed catchments and treated water sources. A total of 25 water samples were collected and examined according to the US EPA-Method 1623, 2005, consisting of 12 from drinking water and 13 from raw water. Positive samples from raw water for Giardia cysts and Cryptosporidium oocysts were 46.1 and 7.6%, respectively. In finished water, positive samples were 41.7% for Giardia cysts and 25.0% for Cryptosporidium oocysts. Concentrations of Giardia cysts found in raw water samples ranged from "not detected" to 3.4 cysts/L, whereas concentrations of Cryptoporidium oocysts ranged from "not detected" to 0.1 oocysts/L. In finished water, Giardia concentrations ranged from "not detected" to 0.06 cysts/L, and Cryptosporidium, from "not detected" to 0.01 oocysts/L. Concentrations of Giardia cysts and Cryptosporidium oocysts were not high in the samples analyzed. Nevertheless, the results of this study highlight the need to monitor these organisms in both raw and drinking water.

Detection rates of waterborne protozoa in water sources from Fayoum Governorate

“…In Egypt, Giardia cysts were detected in different sources of potable water samples with a lower rate (2.1%) in Dakahlia governorate [52] and 7.4% in tap water samples in Gharbiya governorate [43] . Higher detection rates were reported on examination of different water sources in Argentina (31%) [47] and 41.7% in Brazil [44] , while a similar result (15.4%) was recorded in Iran [45]. In a study conducted in Addis Ababa, Ethiopia, the investigators reported a low detection rate in tap water (1%) and a higher rate (29%) in treated water storage tanks [59] .…”

“…For tap water samples, lower detection rates were recorded in Egypt; 3.1% in Dakhahlia governorate [42] , and 13% in Gharbeya governorate [43] . However, the detection rate reaches 25% in Brazil [44] , 34.6% in Iran [45] and 41.6% in Baghdad [46] . Similar results were obtained in El-Minia governorate where the investigators collected 10 ml of water from different water sources (canals, tanks, and tap water) and they detected Cryptosporidium oocysts in 53% of their water samples [19] .…”

Waterborne Giardia and Cryptosporidium: contamination of human drinking water by sewage and cattle feces

“…Although there are no documented data to prove the occurrence of cryptosporidiosis and giardiasis outbreaks and waterborne transmission in Brazil, the presence of these parasites in treated and untreated water made available for human consumption was reported by studies conducted in different regions (HACHICH et al, 2004;HELLER et al, 2004;DIAS et al, 2008;NISHI et al, 2009aNISHI et al, , 2009bMACHADO et al, 2009;RAZZOLINI et al, 2010;TOLEDO et al, 2017). As the main source of contamination of public water supply include the discharge of sanitary sewage and agricultural waste, the occurrence and concentration of these parasites in water bodies in developing countries as well as in rural areas are expected to be greater (HELLER et al, 2004).…”

Quantificação e caracterização genotípica de Cryptosporidium spp.isolados de água bruta superficial e esgoto bruto para a monitorização em mananciais de abastecimento público na Região Metropolitana de São Paulo (RMSP)

“…silvestres (XIAO et al, 2001;SMITH et al, 2006;RYU et al, 2008;RAZZOLINI et al, 2010; BRANCO et al, 2011;JOHNSON et al, 2012).…”

“…Cryptosporidium está descrito entre os protozoários mais frequentemente diagnosticados em casos de surtos associados à água no mundo. Tais ocorrências vêm sendo atribuídas a fatores biológicos e características próprias do parasito Cryptosporidium como, por exemplo, baixa dose infectante necessária para multiplicação no hospedeiro, habilidade em permanecer no ambiente por longos períodos e resistência elevada aos As deficiências no processo de remoção de oocistos durante o tratamento da água e do esgoto e a facilidade de disseminação no ambiente de espécies que afetam o homem demonstraram a necessidade da adoção de um programa de vigilância ativo e bem executado, principalmente em regiões onde a concentração do parasito fosse elevada (OMS, 2003).A detecção e identificação de diferentes espécies de Cryptosporidium em amostras ambientais confirmam a importância de medidas de intervenções para proteção das bacias hidrográficas devido à possibilidade de contaminação dos mananciais por despejo de esgoto tratado e não tratado, resíduos agrícolas e urbanos e dejetos de animais domésticos Introdução 39silvestres (XIAO et al, 2001;SMITH et al, 2006;RYU et al, 2008;RAZZOLINI et al, 2010; BRANCO et al, 2011;JOHNSON et al, 2012).Considerando o potencial de veiculação hídrica na transmissão da criptosporidiose e giardose, em Portugal foi realizado um estudo de investigação molecular associado ao método USEPA 1623 para avaliar 175 amostras de água de diverentes fontes, entre estas, água bruta superficial e água tratada. A presença do parasito Cryptosporidium foi detectada A presença de Cryptosporidium em amostras clínicas foi avaliada em hospitais e universidades (CIMERMAN et al, 2002;GATEI et al, 2003CARVALHO-ALMEIDA et al, 2006OLIVEIRA-SILVA et al, 2007;ARAUJO et al, 2008;GONÇALVES et al, 2008;LUCCA et al, 2009; ASSIS et al, 2013), e a caracterização genética em isolados de fezes de animais silvestres e domésticos evidenciam a ampla distribuição de espécies zoonóticas em diversos estudos no Brasil (MEIRELES et al, 2007;ANTUNES et al, 2008;LALLO et al, 2009;PAZ e SILVA et al, 2013;PAZ e SILVA et al, 2014).…”