Department of Tropical Medicine, Faculty of Medicine, University of Cairo, Departments of Medicine, Howard University School of Medicine, Uniformed Services University for the Health Sciences, Institute for Tropical Medicine, Cairo, Egypt
Epidemiological, clinical, and laboratory data were collected on 537 subjects from Kafr Tarana, a village of 900 inhabitants in the center of the Nile Delta. The purpose of these studies was to better define the long-term morbidity produced by schistosomiasis at the village level. No villager had Schistosoma haematobium infection. The prevalence and intensity of S. mansoni infection was very high; prevalence was 74%, males 78%, females 68%. The geometric mean fecal egg excretion was 208 eggs/g of feces; males 234 eggs/g and females 154 eggs/g. Peak prevalence and intensity of infection was in the age groups between 10 and 40 years. However, most villagers over 40 were still excreting large numbers of eggs. Women who consistently worked in the fields had prevalence and intensity rates similar to those of men, 37% greater than those of women who worked exclusively around the home. Clinical parameters which correlated with intensity of infection were rectal bleeding and hepatosplenomegaly in persons under 20. Hepatic involvement was common, occurring in 144 (27%); 13 individuals had had prior splenectomies for complications of portal hypertension. There was no correlation between the presence of hepatomegaly and prior therapy or the presence of serum hepatitis B surface antigens or antibodies. Surveillance of this village is continuous and plans are in progress to evaluate methods of reducing the prevalence and intensity of infection.