title: Monitoring of Cryptosporidium and Giardia in the Vantaa river basin, southern Finland.
abstract: We compared two sampling methods to assess the contamination of the Vantaa river basin by Giardia cysts and Cryptosporidium oocysts: 10-1 grab samples, the common river mussel Anadonta piscinalis, were analysed for concentration of (oo)cysts from river water. The samples were collected 2-5 times in autumn 2001 from four wastewater treatment plants and four river water sites located downstream of the plants, and six times from raw water of a drinking water plant using the river as water source. The presence of Giardia and Cryptosporidium was analysed by IF microscopy and PCR. Both cysts and oocysts were detected at all sampling sites, but oocysts were more common than cysts in river water samples. In contrast, cysts were more common in A. piscinalis. Most Cryptosporidium-positive samples were of genotype 2 and Giardia were assemblage B. In river water, MPN of Escherichia coli did not correlate to the presence of (oo)cysts. In conclusion, low (oo)cyst counts were regularly identified in the Vantaa river basin which is contaminated by discharges of treated wastewater of human origin. In general, both methods to appropriate to detect (oo)cysts, but grab samples yielded more positive results. Grab sampling is also more practical and less expensive than analysis of A. piscinalis.
authors.affiliation: Department of Food and Environmental Hygiene, University of Helsinki, P.O. Box 57, FIN-00014, Finland. marja-liisa.hanninen@helsinki.f
authors.forename: Marja-Liisa
authors.initials: ML
authors.lastname: Hänninen
authors.forename: Ari
authors.initials: A
authors.lastname: Hörman
authors.forename: Ruska
authors.initials: R
authors.lastname: Rimhanen-Finne
authors.forename: Heli
authors.initials: H
authors.lastname: Vahtera
authors.forename: Serina
authors.initials: S
authors.lastname: Malmberg
authors.forename: Sirpa
authors.initials: S
authors.lastname: Herve
authors.forename: Kirsti
authors.initials: K
authors.lastname: Lahti
mesh_terms: D000818:Animals; D003458:Cryptosporidium / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D004784:Environmental Monitoring / Q000379:methods*; D005387:Finland; D005618:Fresh Water; D005838:Genotype; D016829:Giardia lamblia / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D033661:Oocysts / Q000302:isolation & purification*; D014871:Water Microbiology; D018508:Water Purification