Morbidity due to schistosomiasis was evaluated in a subpopulation of 14,000 of the randomized sample in the Epidemiology 1, 2, 3 Project. It was measured by using a standardized questionnaire for obtaining medical history and symptoms and by performing standardized physical and ultrasound examinations. Reported herein are descriptions of the methods and training and quality control efforts made to insure that the morbidity data was reliable and consistent when collected by 7 different teams in 9 different governorates.

Chronic infection with Schistosoma haematobium primarily causes urinary tract complications. These lesions are often silent or ignored and not detected until irreversible changes have occurred. However, early chemotherapy can prevent progression and usually reverse all but the more severe abnormalities. Recently, abdominal ultrasound has been shown to be an inexpensive, portable and safe means of detecting schistosomal morbidity. A prospective study was performed on 40 patients comparing abdominal radiography, excretory urography (IVP), cystoscopy and ultrasound to detect urinary tract morbidity due to S. haematobium infection. Ultrasound was as sensitive as an IVP in detecting bladder masses, hydronephrosis and renal stones. It detected hydroureter less frequently (sensitivity 62.5%) than an IVP but visualized this lesion and hydronephrosis in some patients with nonfunctioning kidneys. Ultrasound demonstrated bladder stones as well as an x-ray but it detected bladder wall calcification with less sensitivity (65%) and was much less sensitive (12.5%) for detecting ureteral stones.

Parasitological, clinical and ultrasonographical studies were performed upon 422 schoolchildren aged 12-16 years living in a village in the Fayoum where Schistosoma haematobium, but not S. mansoni, was transmitted. Over half of the children gave a history of receiving praziquantel therapy during the preceding 2 years. Symptoms (e.g., haematuria, burning micturition), signs (e.g., hepatomegaly, splenomegaly) and urinary findings (e.g., haematuria, proteinuria) correlated better with the presence and intensity of S. haematobium infection after correcting for this variable. Renal obstructive lesions detected by ultrasound were 2 and 3 times as common in those with moderate and heavy infections as in those with no or light infections, and urinary bladder wall lesions were far more frequent in those with moderate and heavy infections. A mild grade of periportal fibrosis, hepatomegaly and splenomegaly were present in some children in all groups. However, the prevalence of splenomegaly correlated directly with the intensity of infection; liver lesions occurred much more frequently in children with infection or a history of treated infection than in non-infected children denying recent treatment; and no child had hepatomegaly or splenomegaly in the absence of periportal fibrosis.