Prevalence of intestinal parasitic infections in Riyadh district, Saudi Arabia.

A total of 23,516 stool specimens collected from patients attending three medical centres in Riyadh, Saudi Arabia, were examined for intestinal parasites. Of these 5737 (24.4%) were positive. Entamoeba histolytica (8.8%) and Giardia lamblia (6.3%) were the commonest parasites found, and in the age group of one to 15 years. Giardia was found in 14.8% of males and 11.9% of females. Other intestinal parasites present included Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni, Hymeolepis nana. Ancylostoma duodenale, Enterobius vermicularis. Taenia saginata and Schistosoma hematotium.