title: Detection of Cryptosporidium and Giardia (oo)cysts by IFA, PCR and LAMP in surface water from Rasht, Iran.
abstract: BACKGROUND
  Cryptosporidium and Giardia in water supplies is acknowledged as a public health problem. In the present study, we applied immunofluorescence assay (IFA), PCR and loop-mediated isothermal amplification (LAMP) for the detection of the two protozoa.
  
  
  METHODS
  Over a period of 12 months, surface water samples were collected from two rivers in the north of Iran, and filtrated by 142 mm membrane filters. At each sampling point 10 L water were used for IFT and the10 L were analysed using molecular methods.
  
  
  RESULTS
  In 15/40 samples, (oo)cysts were detected by one of the IFA, PCR or LAMP methods. Five samples that were Cryptosporidium-negative by IFA were positive by LAMP. A total of 10 out of 13 samples that were Giardia-positive by IFA were also positive by PCR. IFA revealed high levels of Giardia, with 1-1800 cysts and 1-16 Cryptosporidium oocysts detected per 10 L.
  
  
  CONCLUSIONS
  The study reveals that the investigated water supplies were contaminated by Cryptosporidium and Giardia. The LAMP assay has advantages for detection and screening of these protozoa at relatively low concentration in water samples. The three assays applied are complimentary but no single one will give the true prevalence of these parasites in surface water samples. However, each method has its own advantages and disadvantages dependent of the aim and the study design; a combination of detection methods should be applied to discover whether water is, or is not, contaminated with (oo)cysts. This is the first report on the occurrence of (oo)cysts in Iranian surface waters to compare the results of parasite detection obtained with the different methods.
authors.affiliation: Department of Microbiology, Faculty of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Mahmoudi
authors.forename: Bahram
authors.initials: B
authors.lastname: Kazemi
authors.forename: Anita
authors.initials: A
authors.lastname: Mohammadiha
authors.forename: Asad
authors.initials: A
authors.lastname: Mirzaei
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Karanis
mesh_terms: D000818:Animals; D003458:Cryptosporidium / Q000302:isolation & purification*; D005374:Filtration / Q000379:methods*; D005455:Fluorescent Antibody Technique; D005872:Giardia / Q000302:isolation & purification*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D021141:Nucleic Acid Amplification Techniques; D033661:Oocysts; D016133:Polymerase Chain Reaction; D045483:Rivers / Q000469:parasitology*; D014876:Water Pollution / Q000032:analysis
keywords: Cryptosporidium; Giardia; Iran; LAMP; PCR; Water