Schistosomiasis haematobia in coast province Kenya. Relationship between egg output and morbidity

Several studies of schistosomiasis haematobia in Africa have revealed a correlation between intensity of infection as measured by urine egg counts and severity of disease as determined by intravenous pyelography. The present study consisted of a survey of 390 school children in the coastal area of Kenya involving a single egg count, and intravenous pyelograms in a stratified random sample of 69 children; the results showed a greater prevalence of urinary tract disease in those with higher intensities of infection. This survey was then followed by a more detailed study in which nine consecutive daily egg counts were done on 121 children; 17 of these children, subdivided into three groups with different intensities in infection, were given intravenous pyelograms. The results were similar in the 11 children with minimal and moderate counts (averaging, respectively, less than 1 egg and 167 eggs/10 ml urine daily), with approximately 30% having bladder or renal abnormalities. In comparison, all of the six children with heavy counts (averaging 1,288 eggs/10 ml urine daily) had bladder lesions and five of them had renal lesions.