Detection of human cryplosporidium species in surface water sources in Ismailia using polymerase chain reaction

ABSTRACT

Gryptosporidium is a water-borne parasite that has caused several outbreaks ofgastrointestinal disease worldwide. Two species of Giyptosporidium are mainly found to cause disease in man, C. hominis which shows anthroponotic transmission, and C. parvum with zoonotic transmission. The present study aimed to verify the presence of human Cryplosporidium species in surface water sources in lsmailia using Polymerase Chain Reaction [PCR]. A total of 88 water samples were collected from Ismailia canal [24 samples], and from house taps [64 samples] at different seasons of the year. After filtration and concentration, the water concentrates were examined for Cryplosporidium oocysts by modified Zichi Necisen stain. Identification of C parvum and C. hominis was performed by multiplex allele specific polymerase chain reaction [MAS-PCR] followed by high resolution melting curve [HRM] analysis. The water samples were also subjected to physiochemical and microbiological analysis. Cryplosporidium oocysts were detected in 19[79.2%] of canal water samples and in only 2 [3.1 h] tap samples. Canal water was significantly associated with higher concentration of Cryplosporidium oucysts [50-450 oocysts/L] compared to tap water [20-30 oocysts/L]. C. parvum was the most common species detected in water samples [16 of 21 positive samples, 76.2%], while C. Hominis was detected in only one sample [4.8%] Summer showed the highest percentage of positivity with Cryplosporidium oocysts, then winter followed by autumn and spring. The presence of Cryplosporidium had significant association with the turbidity levels of water samples and their basic pH. Significant associations were also found with presence of total and fecal coliforms. Presence of Cryplosporidium oocysts as significantly associated with the grade >100- 25<103 CFU for both total and fecal coliforms. Canal water was significantly associated with higher concentration of oocysts/L. compared to tap water. C. parvum was found in both sources indicating zoonotic contamination of water