Prevalence of Schistosomes and Soil-Transmitted Helminths among Schoolchildren in Lake Victoria Basin, Tanzania

The objectives of this study was to conduct a survey on schistosomiasis and soil-transmitted helminth (STH) infections in order to come up with feasible control strategies in Lake Victoria basin, Tanzania. Depending on the size of the school, 150-200 schoolchildren were recruited for the study. Duplicate Kato-Katz stool smears were prepared from each child and microscopically examined for Schistosoma mansoni and STHs. Urine specimens were examined for Schistosoma haematobium eggs using the filtration technique. After the survey, mass drug administration was done using praziquantel and albendazole for schistosomiasis and STHs infections, respectively. A total of 5,952 schoolchildren from 36 schools were recruited for the study and had their stool and urine specimens examined. Out of 5,952 schoolchildren, 898 (15.1%) were positive for S. mansoni, 754 (12.6%) for hookworms, 188 (3.2%) for Ascaris lumblicoides, and 5 (0.008%) for Trichuris trichiura. Out of 5,826 schoolchildren who provided urine samples, 519 (8.9%) were positive for S. haematobium eggs. The results revealed that intestinal schistosomiasis, urogenital schistosomiasis, and STH infections are highly prevalent throughought the lake basin. The high prevalence of intestinal and urogenital schistosomisiasis in the study area was a function of the distance from Lake Victoria, the former being more prevalent at localities close to the lake, whilst the latter is more so away from it. Control of schistosomiasis and STHs in the study area requires an integrated strategy that involves provision of health education to communities, regular treatments, and provision of adequate safe water supply and sanitation facilities.

Prevalence of Schistosomes and Soil-Transmitted Helminths and Morbidity Associated with Schistosomiasis among Adult Population in Lake Victoria Basin, Tanzania

The objective of this study was to carry out a community survey on schistosomiais and soil-transmitted helminth (STH) infections in order to suggest feasible and effective intervention strategies in Lake Victoria basin, Tanzania. A total of 37 communities selected from 23 districts of the 4 regions in the Lake Victoria basin of Tanzania were involved in the study. From each of the selected locality, 50 adult community members, 25 males and 25 females, were recruited for the study. Each study participant was requested to submit stool and urine specimens. From each stool specimen, duplicate Kato-Katz thick smears were prepared and microscopically examined for Schistosoma mansoni and STH eggs. Urine specimens were processed by the filtration technique and microscopically examined for Schistosoma haematobium eggs. Ultrasound examination for morbidity due to schistosomiasis was performed. Mass treatment was done using praziquantel and albendazole for schistosome and STHs infections, respectively. Out of 1,606 adults who provided stool specimens, 199 (12.4%) were positive for S. mansoni, 349 (21.7%) for hookworms, 133 (8.3%) for Ascaris lumbricoides, and 33 (2.0%) for Trichuris trichiura. Out of 1,400 participants who provided urine specimens, 25 (1.8%) were positive for S. haematobium eggs. Because of the co-endemicity of these afflictions and their impact on vulnerable population groups, the helminthiasis could be simultaneously treated with 2 drugs, praziquantel for schistosomiasis and albendazole for STHs.

Anti-Mycobacterial and Toxicity Activities of Some Priority Medicinal Plants from Lake Victoria Basin, Tanzania.

Aims: This study has evaluated ethanol extracts from five medicinal plants selected through ethnobotanical study from Lake Victoria basin, Tanzania for their in vitro antimycobacterial activity against two Mycobacterium species and cytotoxicity against brine shrimp larvae. Study Design: Laboratory experimental tests. Place and Duration of Study: Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, P.O. Box 65001, Dar es Salaam, Tanzania, between July 2010 and July 2011. Methodology: Five medicinal plants were selected from the priority list obtained from Lake Victoria basin, Tanzanian side. Collection, processing and drying of plant samples were done in the field with the assistance of a botanist while extraction and concentration of plant samples to obtain crude extracts were done in the laboratory following standard procedures. The plants included in this study are Antidesma membranaceum, Crassocephalum manii, Entada abyssinica, Croton dichogamus and Rubia cordifolia. The two fold microdilution method was used to determine the MIC values of extracts against two Mycobacterium marker strains (Mycobacterium indicus pranii and Mycobacterium madagascariense). The cytotoxicity of plant extract was evaluated against brine shrimp larvae. Furthermore, the extracts were screened phytochemicaly to establish the group of compounds responsible for the activity. Results: Among the tested extracts, the stem bark of A. membranaceum and C. manii showed moderate to mild activity against M. indicus pranii (MIC = 0.3125 mg/ml) and M. madagascariense (MIC = 0.625 mg/ml) respectively. Furthermore, A. membranaceum exhibited significant toxicity activity with LC50 value of 36.134 μg/ml against brine shrimp larvae. Other plants were moderately active when tested in vitro against the above organisms. Phytochemical screening of extracts indicated the presence of different classes of compounds. Conclusion: This study has shown the potential of the priority medicinal plant extracts to be the source of possible lead compounds and anti‐TB drug candidates needed for the management of Tuberculosis. Isolation of active principles from active fractions will be further undertaken.