First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species

Siqueira-Castro, Isabel Cristina Vidal; Greinert-Goulart, Juliane Araújo; Bonatti, Taís Rondello; Yamashiro, Sandra; Franco, Regina Maura Bueno

doi:10.1007/s11356-016-6689-y

Cited by 18 publications

(16 citation statements)

References 34 publications

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“…(4). While laboratory feeding experiments suggest that protozoan predators do feed on both of these groups under controlled conditions (171,172), additional work is needed to verify their role under ambient conditions.…”

Section: Extrinsic Factorsmentioning

confidence: 99%

Persistence and Decay of Fecal Microbiota in Aquatic Habitats

Korajkic

Wanjugi

Brooks

et al. 2019

Microbiol Mol Biol Rev

100

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SUMMARY Fecal microorganisms can enter water bodies in diverse ways, including runoff, sewage discharge, and direct fecal deposition. Once in water, the microorganisms experience conditions that are very different from intestinal habitats. The transition from host to aquatic environment may lead to rapid inactivation, some degree of persistence, or growth. Microorganisms may remain planktonic, be deposited in sediment, wash up on beaches, or attach to aquatic vegetation. Each of these habitats offers a panoply of different stressors or advantages, including UV light exposure, temperature fluctuations, salinity, nutrient availability, and biotic interactions with the indigenous microbiota (e.g., predation and/or competition). The host sources of fecal microorganisms are likewise numerous, including wildlife, pets, livestock, and humans. Most of these microorganisms are unlikely to affect human health, but certain taxa can cause waterborne disease. Others signal increased probability of pathogen presence, e.g., the fecal indicator bacteria Escherichia coli and enterococci and bacteriophages, or act as fecal source identifiers (microbial source tracking markers). The effects of environmental factors on decay are frequently inconsistent across microbial species, fecal sources, and measurement strategies (e.g., culture versus molecular). Therefore, broad generalizations about the fate of fecal microorganisms in aquatic environments are problematic, compromising efforts to predict microbial decay and health risk from contamination events. This review summarizes the recent literature on decay of fecal microorganisms in aquatic environments, recognizes defensible generalizations, and identifies knowledge gaps that may provide particularly fruitful avenues for obtaining a better understanding of the fates of these organisms in aquatic environments.

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Section: Extrinsic Factorsmentioning

confidence: 99%

Persistence and Decay of Fecal Microbiota in Aquatic Habitats

Korajkic

Wanjugi

Brooks

et al. 2019

Microbiol Mol Biol Rev

100

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“…Na ETE Piçarrão, no município de Campinas, Siqueira-Castro et al (2016) observaram que os ciliados de vida livre Euplotes aediculatus e Sterkiella cavicola componentes na microfauna do sistema de lodo ativado demonstraram potencial predatório sobre oocistos de Cryptosporidium spp. e cistos de Giardia spp.…”

Section: Parâmetros Físicos Químicos E Microbiológicosunclassified

Remoção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. na Estação de Tratamento de Esgoto Garcia, no município de Blumenau, SC, Brasil

Miglioli¹,

Zuanazzi²,

Silva³

et al. 2017

Rev. ambiente água

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Giardia spp. and Cryptosporidium spp. are responsible for a number of outbreaks of gastroenteritis, particularly associated with the consumption of contaminated water. The cysts and oocysts of these protozoa are resistant to environmental variations, as well as to most of the physical, chemical and microbiological processes used in water treatment and sewage plants. This study therefore aimed to detect and evaluate the removal of Giardia spp. and Cryptosporidium spp. in a combined system anaerobic / aerobic Waste Water Treatment Plant (WWTP) located in the city of Blumenau, SC, Brazil. For the study of cysts and oocysts, samples of effluents and sludge from the WWTP were concentrated by filtration using a membrane of cellulose esters and by centrifugation, followed by direct immuno-fluorescence assay (RID) using the Merifluor diagnostic kit. The analysis followed the standards published in APHA (2012) to obtain the physical, chemical and microbiological parameters. High concentrations of Giardia spp. (Max. 900,000 L -1 cysts) were detected in 83.3% of the analyzed points. Oocysts Cryptosporium spp. were detected at high concentrations (max. 300,000 oocysts L -1 ) in 66.6% of the analyzed points. Neither cysts nor oocysts were detected in treated effluent samples. Thus, the combined system of the Garcia WWTP showed a 99.9% efficiency rate for the removal of resistant forms of pathogens, contributing to the reduction of environmental contamination by these pathogens present in the domestic sewage of Blumenau, SC.

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“…Studies by Siqueira‐Castro et al . () recently reported that ciliated free‐living protozoa, Euplotes aediculatus and Sterkiella cavicola , which are found in fresh water and wastewater treatment plants (e.g. activated sludge), are capable of ingesting Giardia cysts.…”

Section: Discussionmentioning

confidence: 99%

Differences in staining intensities affect reported occurrences and concentrations ofGiardiaspp. in surface drinking water sources

Alderisio¹,

Villegas

Ware

et al. 2017

J Appl Microbiol

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Aim USEPA Method 1623, or its equivalent, is currently used to monitor for protozoan contamination of surface drinking water sources worldwide. At least three approved staining kits used for detecting Cryptosporidium and Giardia are commercially available. This study focuses on understanding the differences among staining kits used for Method 1623. Methods and Results Merifluor and EasyStain labeling kits were used to monitor Cryptosporidium oocyst and Giardia cyst densities in New York City’s raw surface water sources. In the year following a change to the approved staining kits for use with Method 1623, an anomaly was noted in the occurrence of Giardia cysts in New York City’s raw surface water. Specifically, Merifluor-stained samples had higher Giardia cyst densities as compared with those stained with EasyStain. Side by side comparison revealed significantly lower fluorescence intensities of Giardia muris as compared with G. duodenalis cysts when labeled with EasyStain. Conclusions This study showed very poor fluorescence intensity signals by EasyStain on G. muris cysts results in lower cyst counts, while Merifluor, with its broader Giardia cyst staining specificity, results in higher cyst counts, when using Methods 1623. Significance and Impact of Study These results suggest that detected Giardia cyst concentrations are dependent on the staining kits used, which can result in a more or less conservative estimation of occurrences and densities of zoonotic Giardia cysts by detecting a broader range of Giardia species/Assemblages.

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First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species

Cited by 18 publications

References 34 publications

Persistence and Decay of Fecal Microbiota in Aquatic Habitats

Persistence and Decay of Fecal Microbiota in Aquatic Habitats

Remoção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. na Estação de Tratamento de Esgoto Garcia, no município de Blumenau, SC, Brasil

Differences in staining intensities affect reported occurrences and concentrations ofGiardiaspp. in surface drinking water sources

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