title: Occurrence and potential health risk of Cryptosporidium and Giardia in different water catchments in Belgium.
abstract: Human wastewater and livestock can contribute to contamination of surface water with Cryptosporidium and Giardia. In countries where a substantial proportion of drinking water is produced from surface water, e.g., Belgium, this poses a constant threat on drinking water safety. Our objective was to monitor the presence of Cryptosporidium and Giardia in different water catchment sites in Belgium and to discriminate between (oo)cysts from human or animal origin using genotyping. Monthly samples were collected from raw water and purified drinking water at four catchment sites. Cryptosporidium and Giardia were detected using USEPA method 1623 and positive samples were genotyped. No contamination was found in purified water at any site. In three catchments, only low numbers of (oo)cysts were recovered from raw water samples (<1/liter), but raw water samples from one catchment site were frequently contaminated with Giardia (92 %) and Cryptosporidium (96 %), especially in winter and spring. Genotyping of Giardia in 38 water samples identified the presence of Giardia duodenalis assemblage AI, AII, BIV, BIV-like, and E. Cryptosporidium andersoni, Cryptosporidium suis, Cryptosporidium horse genotype, Cryptosporidium parvum, and Cryptosporidium hominis were detected. The genotyping results suggest that agriculture may be a more important source of surface water contamination than human waste in this catchment. In catchment sites with contaminated surface water, such as the Blankaart, continuous monitoring of treated water for the presence of Cryptosporidium and Giardia would be justified and (point) sources of surface water contamination should be identified.
authors.affiliation: Laboratory for Parasitology, Ghent University, Merelbeke, Belgium.
authors.forename: Amimul
authors.initials: A
authors.lastname: Ehsan
authors.forename: Thomas
authors.initials: T
authors.lastname: Geurden
authors.forename: Stijn
authors.initials: S
authors.lastname: Casaert
authors.forename: Jef
authors.initials: J
authors.lastname: Paulussen
authors.forename: Lut
authors.initials: L
authors.lastname: De Coster
authors.forename: Toon
authors.initials: T
authors.lastname: Schoemaker
authors.forename: Rachel
authors.initials: R
authors.lastname: Chalmers
authors.forename: Grietje
authors.initials: G
authors.lastname: Grit
authors.forename: Jozef
authors.initials: J
authors.lastname: Vercruysse
authors.forename: Edwin
authors.initials: E
authors.lastname: Claerebout
mesh_terms: D000818:Animals; D001530:Belgium / Q000453:epidemiology; D003457:Cryptosporidiosis / Q000453:epidemiology*; D003458:Cryptosporidium / Q000145:classification / Q000254:growth & development; D004784:Environmental Monitoring; D005618:Fresh Water / Q000469:parasitology*; D005838:Genotype; D005872:Giardia / Q000145:classification / Q000254:growth & development; D005873:Giardiasis / Q000453:epidemiology*; D006801:Humans; D012306:Risk; D014876:Water Pollution / Q000706:statistics & numerical data; D018508:Water Purification; D014881:Water Supply / Q000706:statistics & numerical data