Occurrence of Cryptosporidium and Giardia in Drinking Water Sources in Plateau State

Cryptosporidium and Giardia are leading protozoan causes of waterborne diarrheal disease globally, and their detection in drinking water sources represents a significant public health concern. This study determined the occurrence and distribution of Cryptosporidium oocysts and Giardia cysts in drinking water sources across three local government areas of Plateau State, in the North Central geopolitical zone of Nigeria. Water samples were collected monthly over six months from 15 sites including rivers, springs, and taps. The US Environmental Protection Agency Method 1623 was employed for concentration and detection using immunofluorescence microscopy. Cryptosporidium oocysts were detected in 46.7 percent of sampled sites, and Giardia cysts were found in 60 percent of sites. River and spring water samples had significantly higher protozoan loads compared to treated tap water. The rainy season was associated with markedly elevated parasite counts. These findings confirm that drinking water sources in Plateau State harbor pathogenic protozoa at levels exceeding safe thresholds, placing communities at sustained risk of waterborne disease. The study advocates for water treatment improvements including filtration and regular protozoan monitoring at water supply points. Community sensitization on water boiling and the use of household water treatment options are also recommended. Keywords: Cryptosporidium, Giardia, drinking water, Plateau State, waterborne protozoa.