Development of Sensitive Detection of Cryptosporidium and Giardia from Surface Water in Iran

BACKGROUND The protozoan parasites Cryptosporidium spp. and Giardia are known to occur widely in both raw and drinking waters. They are two of the causative agents of waterborne outbreaks of gastroenteritis throughout the world. In the present study, a PCR assay and FA were developed for detection of Cryptosporidium oocysts and Giardia cyst in environmental samples. METHODS We have detected Cryptosporidium spp. oocysts and Giardia cysts in seeded and unseeded environmental water samples by PCR method. Water samples were spiked with oocysts (50, 100,300,500) and filtrated with a 1.2-µm pore size cellulose nitrate and follow by DNA extraction and purification by QIAamp DNA mini kit. Nested-PCR assay amplified an 850 bp fragment of 18s rRNA gene specific for Cryptosporidium and 435 bp fragment of glutamate dehydrogenase (GDH) target gene for Giardia. Also many river water from north of Iran, be checked by these methods. RESULTS Cryptosporidium and Giardia DNAs were detected in seeded water sample and Giardia was detected in all 5 water samples from river in north of Iran by nested- PCR and FA. Also in one river water sample, Cryptosporidium was detected. CONCLUSION This protocol is effective for detection of these waterborne parasites in treated and untreated water samples. This study can also serve as a platform for further investigations and research water source in Iran.