[Epidemiological baseline situation before the construction of a small dam in five villages of Bouaké, central Côte-d'Ivoire]. / Situation épidémiologique avant la mise en eau du barrage hydroagricole de cinq villages de Bouaké, centre Côte-d'Ivoire

Abstract From June 2007 to June 2008, entomological, malacological and parasitological investigations were carried out in five villages in close proximity to a small dam of Raf-fierkro in Bouaké, central Côte-d'Ivoire. The objective of the study was to identify vectors and intermediate host snails of parasitic diseases related to water, and to assess the prevalence of malaria, schistosomiasis and soil-transmitted helminthiasis before dam construction. Mosquitoes were caught by human landing catches, snails were collected in water bodies, and microscopic analyses of blood, stool and urine samples were carried out. Two malaria vector species were identified:Anopheles gambiae and Anopheles funestus. The average infective rate of An. gambiae ranged between 3.1 and 4.5 %. The infective rate of An. funestus was 1 % in all sites. The entomological inoculation rate ranged between 343.1 and 427.1 infective bites per person per year (ib/p/y)for An. gambiae and between 14.6 and 40.1 ib/p/y for An. funestus. Three species of were found: Plasmodium falciparum (predominant species), Plasmodium ovale and Plasmodium malariae. There were no intermediate host snails of schistosomiasis with the exception of Biomphalaria pfeifferi,intermediate host snail of Schistosoma mansoni in Ahougui. The prevalence of urinary and intestinal schistosomiasis and soil-transmitted helminthiasis was low. Our studies revealed important transmission of malaria, with the presence of three plasmodial species, whereas schistosomiasis and soil-transmitted helminthiasis were present, but only at low frequencies.

Control of urinary schistosomiasis: an investigation into the effective use of questionnaires to identify high-risk communities and individuals in Niger State, Nigeria.

Schistosomiasis is a public health problem in Nigeria. Although there is a national programme for its control, there is the need for reliable and simple means of rapidly diagnosing communities to provide a detailed map on the distribution of the disease in the country, in order to prioritize control activities, as well as to monitor the effectiveness of control operations. A rapid assessment technique using school questionnaires was tested in Borgu Local Government Area (LGA), Niger State, north-western Nigeria. Following a series of focus group discussions, the questionnaires were adapted before they were administered through the school system to 60 primary schools in Borgu LGA. Correctly completed questionnaires were returned from 58 schools (97%) within 4 weeks. Questionnaires were validated by reagent stick tests performed by trained teachers. Their results proved to be reliable compared to those obtained by our research team in 20 randomly selected schools. Overall prevalences of microhaematuria at 1+ and 2+ levels were 45.7% and 27. 1%, respectively. Highly significant correlations were obtained between school prevalence of microhaematuria and reported schistosomiasis, as well as reported blood in urine. The diagnostic performance of the questionnaires at the 2+ level of microhaematuria was very good. The design of our study also allowed data analysis on an individual level, and multivariate analysis revealed highly significant odds ratios for reported schistosomiasis and reported blood in urine to detect an individual with urinary schistosomiasis. Our results are in good agreement with reports from other African countries, and questionnaires can be recommended for rapid identification of communities at highest risk of urinary schistosomiasis in Nigeria, so that scarce resources of the national control programme can be used most effectively.