Evaluation of various techniques used for the diagnosis of Schistosomiasis
الملخص
The main objective of the study was to determine the rates of prevalence for both species of Schistosoma amongst the population with special emphasis on school children. Moreover, the study aimed at the determination of sensitivity of various techniques for the diagnosis of each of the two Schistosoma species.
1000 specimens were, in total, collected; 500 samples of urine and 500 samples of stool from the population in the area around Sinnar city. The surrounding environment and social behavior of the communities were taken into consideration, especially the habits that aid the spread of infection. For stool detection, direct faecal smear, formal ether centrifugation technique, formal detergent quantitative technique, ordinary kato technique, and modified kato-katz technique were used. For urine detection, sedimentation technique by centrifugation, sedimentation technique by gravity, and filtration technique were used.
The overall rate of prevalence of S. mansoni was 24.8%, while S. haematobium was 43.0%. Amongst the diagnostic methods for the examination of the samples, formal ether technique proved to be the most sensitive (24.8%) for detecting and determining the mean egg count of S. mansoni, while filtration technique proved to be the most sensitive (43.8%) for detecting and determining the mean egg count for S. haematobium. Other methods showed relatively less sensitivity and quantitative efficiency
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