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The purpose of this article is to describe the findings of a study carried out in a cohort of 610 schoolchildren aged 6-15 years to determine the prevalence of urinary schistosomiasis in Wilaya of Gorgol. The schistosomiasis prevalence rate was high ranging from 1.3 to 30.1% depending on location and from 7.9 to 13.7% according to age. Parasite loads up to 14 eggs/10 mL were measured. Children living in the wet zone were significantly more infected than those living in the intermediate and dry zones (p = 0.005). However, no significant difference in prevalence was found according to age (p = 0.258). Infection rate and parasite burden were correlated with exposure in terms of frequency of contact with permanent water sources. Schoolchildren in frequent contact with breeding grounds were more vulnerable to urinary schistosomiasis. Areas along the riverbank were more affected than areas located away from the river or permanent water sources. Source

Lai Y.-S.,Swiss Tropical and Public Health Institute | Biedermann P.,Swiss Tropical and Public Health Institute | Ekpo U.F.,Abeokuta Federal University of Agriculture | Garba A.,Reseau International Schistosomose | And 15 more authors.
The Lancet Infectious Diseases

Background: Schistosomiasis affects more than 200 million individuals, mostly in sub-Saharan Africa, but empirical estimates of the disease burden in this region are unavailable. We used geostatistical modelling to produce high-resolution risk estimates of infection with Schistosoma spp and of the number of doses of praziquantel treatment needed to prevent morbidity at different administrative levels in 44 countries. Methods: We did a systematic review to identify surveys including schistosomiasis prevalence data in sub-Saharan Africa via PubMed, ISI Web of Science, and African Journals Online, from inception to May 2, 2014, with no restriction of language, survey date, or study design. We used Bayesian geostatistical meta-analysis and rigorous variable selection to predict infection risk over a grid of 1 155 818 pixels at 5 × 5 km, on the basis of environmental and socioeconomic predictors and to calculate the number of doses of praziquantel needed for prevention of morbidity. Findings: The literature search identified Schistosoma haematobium and Schistosoma mansoni surveys done in, respectively, 9318 and 9140 unique locations. Infection risk decreased from 2000 onwards, yet estimates suggest that 163 million (95% Bayesian credible interval [CrI] 155 million to 172 million; 18·5%, 17·6-19·5) of the sub-Saharan African population was infected in 2012. Mozambique had the highest prevalence of schistosomiasis in school-aged children (52·8%, 95% CrI 48·7-57·8). Low-risk countries (prevalence among school-aged children lower than 10%) included Burundi, Equatorial Guinea, Eritrea, and Rwanda. The numbers of doses of praziquantel needed per year were estimated to be 123 million (95% CrI 121 million to 125 million) for school-aged children and 247 million (239 million to 256 million) for the entire population. Interpretation: Our results will inform policy makers about the number of treatments needed at different levels and will guide the spatial targeting of schistosomiasis control interventions. Funding: European Research Council, China Scholarship Council, UBS Optimus Foundation, and Swiss National Science Foundation. © 2015 Elsevier Ltd. Source

Ould Ahmed Salem C.B.,Institute National Of Recherche En Sante Publique | Schneegans F.,Center National Delevage Et Of Recherche Veterinaire | Chollet J.Y.,Center National Delevage Et Of Recherche Veterinaire | Jemli M.H.,Ecole Nationale de Medecine Veterinaire
Iranian Journal of Parasitology

Background: Echinococcosis/hydatidosis is considered endemic in Mauritania. The aim of this study is to present an epidemiological study on the echinococcosis in man and animals in the Nouakchott region. Methods: The internal organs from livestock carcasses were inspected for research of hydatid cysts. The hydatid fluid was examined for research of the protoscoleces. Dogs were necropsied for the collect of Echinococcus granulosus. Results: In the Nouakchott Hospital, 24 surgical operation of human hydatid cysts have been performed, out of which 50% were localised in the lung, 33% in the liver and 17% elsewhere. Then, the incidence rate would be of 1.2% per 100 000 inhabitants in Mauritania. In the dog, the prevalence rate is 14%. The average number of E. granulosus on the whole dogs is 172 and 1227 on the positive dogs. Concerning the livestock, hydatid cysts found in 30.1% of the dromedary, 5.5% of the cattle and 6.5 of the sheep. The fertility rate of hydatid cysts in humans (75%) and camels (76%) was significantly higher than that of sheep (24%) and cattle (23%) (P<0.0001). Hydatid infestation is characterized globally by the dominance of pulmonary localizations in humans (50%) and camels (72.7%) and in the liver in sheep (76.1%) and cattle (82.3%). Conclusion: The differences between prevalence rates, the fertility of hydatid cysts and diversity sites localization observed in humans and camels of one hand and the sheep and cattle on the other hand, depends possibly the strain(s) diversity of E. granulosus. Source

Pham A.T.,University of Oslo | Malterud K.E.,University of Oslo | Paulsen B.S.,University of Oslo | Diallo D.,Institute National Of Recherche En Sante Publique | Wangensteen H.,University of Oslo
Natural Product Communications

From a methanol extract of the leaves of the Malian medicinal tree Terminalia macroptera, cis-polyisoprene (1), chebulic acid trimethyl ester (2), methyl gallate (3), shikimic acid (4), corilagin (5), rutin (6), narcissin (7), chebulagic acid (8) and chebulinic acid (9), were isolated. Cispolyisoprene (1) was the major non-polar constituent. The novel compound 2 showed high radical scavenging activity (IC 50 4.7 μg/mL), but was inactive as xanthine oxidase inhibitor. The major substituent of the crude extract, substance 5, showed a high radical scavenger effect (IC 50 2.7 μg/mL) and weak xanthine oxidase inhibition (IC 50 ca 105 μg/mL). The antioxidant and radical scavenging effects of some of the substances identified in this study may to some extent explain the medical use of this tree in West Africa. Source

Karagiannis-Voules D.-A.,Swiss Tropical and Public Health Institute | Karagiannis-Voules D.-A.,University of Basel | Biedermann P.,Swiss Tropical and Public Health Institute | Biedermann P.,University of Basel | And 21 more authors.
The Lancet Infectious Diseases

Background: Interest is growing in predictive risk mapping for neglected tropical diseases (NTDs), particularly to scale up preventive chemotherapy, surveillance, and elimination efforts. Soil-transmitted helminths (hookworm, Ascaris lumbricoides, and Trichuris trichiura) are the most widespread NTDs, but broad geographical analyses are scarce. We aimed to predict the spatial and temporal distribution of soil-transmitted helminth infections, including the number of infected people and treatment needs, across sub-Saharan Africa. Methods: We systematically searched PubMed, Web of Knowledge, and African Journal Online from inception to Dec 31, 2013, without language restrictions, to identify georeferenced surveys. We extracted data from household surveys on sources of drinking water, sanitation, and women's level of education. Bayesian geostatistical models were used to align the data in space and estimate risk of with hookworm, A lumbricoides, and T trichiura over a grid of roughly 1 million pixels at a spatial resolution of 5 × 5 km. We calculated anthelmintic treatment needs on the basis of WHO guidelines (treatment of all school-aged children once per year where prevalence in this population is 20-50% or twice per year if prevalence is greater than 50%). Findings: We identified 459 relevant survey reports that referenced 6040 unique locations. We estimate that the prevalence of hookworm, A lumbricoides, and T trichiura among school-aged children from 2000 onwards was 16·5%, 6·6%, and 4·4%. These estimates are between 52% and 74% lower than those in surveys done before 2000, and have become similar to values for the entire communities. We estimated that 126 million doses of anthelmintic treatments are required per year. Interpretation: Patterns of soil-transmitted helminth infection in sub-Saharan Africa have changed and the prevalence of infection has declined substantially in this millennium, probably due to socioeconomic development and large-scale deworming programmes. The global control strategy should be reassessed, with emphasis given also to adults to progress towards local elimination. Funding: Swiss National Science Foundation and European Research Council. © 2015 Elsevier Ltd. Source

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