SCHISTOSOMA-HAEMATOBIUM INFECTION IN WESTERN MADAGASCAR - MORBIDITY DETERMINED BY ULTRASONOGRAPHY

To assess the morbidity related to Schistosoma haematobium infection i n western Madagascar, an ultrasonographic examination was performed of 574 inhabitants >5 years old in a village in an old-established endem ic area where no prior systematic antischistosomal treatment had been given. The overall prevalence of infection was 75.9% and the geometric mean egg count of positive individuals was 36 eggs/10 mt of urine. Re cent haematuria had been experienced by 31.8% of individuals. Echograp hic abnormalities of the urinary tract were present in 50.5% of indivi duals: they were more frequent in males. Bladder wall lesions were obs erved in 93.1% of individuals with ultrasonographic changes, irregular ities of the inner surface being the most comon finding. Congestive ch anges were noted in 8.4% of kidneys, but we observed only 4 severe con gestions. Bladder lesions and congestive changes in kidneys predominat ed in youth; their presence and severity were significantly correlated with egg excretion. In 12 inhabitants, grade 1 periportal fibrosis wa s observed, but no significant association was found with S. haematobi um infection. In a control village, where the prevalence of S. haemato bium infection was 7%, moderate congestion of kidneys was observed in 2% of examined inhabitants, and bladder changes in 6%, with a signific ant relationship with S. haematobium infection.