Spatial and temporal variation of malaria entomological parameters at the onset of a hydro-agricultural development in central Côte d'Ivoire

A deeper understanding of the ecology and small-scale heterogeneity of malaria transmission is essential for the design of effective prevention, control and elimination interventions. The spatial and temporal distribution of malaria vectors was investigated in five villages in close proximity to a hydro-agricultural system in Côte d'Ivoire over the course of construction and the early phase of irrigated rice farming.; The study was carried out in five villages (Raffierkro, N'Douakro, Ahougui, Kpokahankro, Koffikro) near Bouaké, central Côte d'Ivoire, between early 2007 and late 2009. In each village, mosquitoes were collected by human landing catches and identified morphologically at genus and species level, and entomological parameters were determined. Plasmodium infection was assessed by dissection and an enzyme-linked immunosorbent assay.; A total of 19,404 mosquitoes belonging to the genus Anopheles were sampled during 328 human-night catches. Before the construction of the hydro-agricultural system, comparable densities of Anopheles gambiae were observed in all villages. In subsequent years, densities in Raffierkro and Ahougui were significantly higher than the other villages [Kruskal-Wallis (KW) test = 31.13, p > 0.001]. The density of Anopheles funestus in the five villages was comparable in the early stage of the project, while a high density was reported in Koffikro at the end (KW test = 11.91, p = 0.018). Transmission of Plasmodium falciparum is perennial in the study area. Over the course of the study, high entomological inoculation rates (EIRs) were found: 219-328 infectious bites per person per year with An. gambiae. For An. funestus considerably lower EIRs were observed (5.7-39.4). Changing patterns of An. gambiae were not correlated with malaria transmission.; In this study setting, located in the bioclimatic transition zone of Côte d'Ivoire, rice cultivation was not observed to increase malaria transmission. The entomological parameters recorded until the onset of rice-growing activities in a hydro-agricultural system presented considerable heterogeneity both in space and time; a strong increase of Anopheles mosquitoes was observed in two of the five villages located in close proximity to the dam and irrigated rice fields. Malaria still is a main public health problem in all villages that require adequate control measures

Efficacy and safety of moxidectin, synriam, synriam-praziquantel versus praziquantel against schistosoma haematobium and S. mansoni infections: a randomized, exploratory phase 2 trial

Schistosomiasis affects millions of people, yet treatment options are limited. The antimalarial Synriam (piperaquine 150 mg/arterolane 750 mg) and the anthelminthic moxidectin revealed promising antischistosomal properties in preclinical or clinical studies.; We conducted two single-blind, randomized exploratory Phase 2 trials in Schistosoma mansoni and S. haematobium-infected adolescents in northern and central Côte d'Ivoire. Our primary endpoints were cure rates (CRs) and egg reduction rates (ERRs) based on geometric mean and safety. Each subject was asked to provide two stool samples (S. mansoni trial) for Kato-Katz analysis or three urine samples (S. haematobium trial) for urine filtration and one finger prick for malaria screening at baseline and follow-up. Participants were randomly assigned to either moxidectin, Synriam, Synriam plus praziquantel or praziquantel.; 128 adolescents (age: 12-17 years) were included in each study. Against S. haematobium moxidectin and Synriam revealed low efficacy. On the other hand, Synriam plus praziquantel and praziquantel yielded CRs of 60.0% and 38.5% and ERRs of 96.0% and 93.5%, respectively. CRs observed in the treatment of S. mansoni were 13.0%, 6.7%, 27.0%, and 27.6% for moxidectin, Synriam, Synriam plus praziquantel and praziquantel, respectively. ERRs ranged from 64.9% (Synriam) to 87.5% (praziquantel).; Synriam and moxidectin show low efficacy against S. haematobium, hence an ancillary benefit is not expected when these drugs are used for treating onchocerciasis and malaria in co-endemic settings. Further studies are needed to corroborate our findings that moxidectin and Synriam show moderate ERRs against S. mansoni

Efficacy and safety of praziquantel in preschool-aged children in an area co-endemic for Schistosoma mansoni and S. haematobium

BACKGROUND: In sub-Saharan Africa the recommended strategy to control schistosomiasis is preventive chemotherapy. Emphasis is placed on school-aged children, but in high endemicity areas, preschool-aged children are also at risk, and hence might need treatment with praziquantel. Since a pediatric formulation (e.g., syrup) is not available outside of Egypt, crushed praziquantel tablets are used, but the efficacy and safety of this treatment regimen is insufficiently studied.METHODOLOGY: We assessed the efficacy and safety of crushed praziquantel tablets among preschool-aged children (>6 years) in the Azaguié district, south Côte d'Ivoire, where Schistosoma mansoni and S. haematobium coexist. Using a cross-sectional design, children provided two stool and two urine samples before and 3 weeks after treatment. Crushed praziquantel tablets, mixed with water, were administered at a dose of 40 mg/kg. Adverse events were assessed and graded 4 and 24 hours posttreatment by interviewing mothers/guardians.PRINCIPAL FINDINGS: Overall, 160 preschool-aged children had at least one stool and one urine sample examined with duplicate Kato-Katz thick smears and a point-of-care circulating cathodic antigen (POC-CCA) cassette for S. mansoni, and urine filtration for S. haematobium diagnosis before and 3 weeks after praziquantel administration. According to the Kato-Katz and urine filtration results, we found high efficacy against S. mansoni (cure rate (CR), 88.6%; egg reduction rate (ERR), 96.7%) and S. haematobium (CR, 88.9%; ERR, 98.0%). POC-CCA revealed considerably lower efficacy against S. mansoni (CR, 53.8%). Treatment was generally well tolerated, but moderately severe adverse events (i.e., body and face inflammation), were observed in four Schistosoma egg-negative children. CONCLUSIONS/SIGNIFICANCE: Crushed praziquantel administered to preschool-aged children at a dose of 40 mg/kg is efficacious against S. mansoni and S. haematobium in a co-endemic setting of Côte d'Ivoire. Further research is required with highly sensitive diagnostic tools and safety must be investigated in more depth.TRIAL REGISTRATION: Controlled-Trials.com ISRCTN53172722

Evaluation de l’effet repulsif d’extraits de neem (Azadirachta indica A. Juss., 1830) sur le charançon de la patate douce (Cylas puncticollis Boheman, 1833) en condition de laboratoire a Korhogo, nord de la Cote d’Ivoire

Une stratégie de gestion intégrée des insectes nuisibles à la culture de la patate douce a été élaborée pour réduire les pertes dues à ceux-ci. Ainsi, les propriétés répulsives des extraits de feuilles et d’amandes de neem ont été évaluées sur Cylas puncticollis, un charançon de la patate douce. Pour ce faire, quatre concentrations d’extraits ont été préparées à raison de quatre répétitions par concentration. Le test a consisté à la détermination du pourcentage de charançons présents dans la zone traitée. Chacune des concentrations d’extraits a été appliquée sur la moitié d’un papier buvard placé dans une boite de Pétri de 9 cm de diamètre et sur lequel 10 charançons ont été posés. Les effets répulsifs des extraits ont été comparés à ceux d’un insecticide chimique et l’eau distillée. Le test avec 20 cL/L d’extraits de feuilles a causé 85 % de répulsion contre 45 % pour les amandes à 25 g/L. Les extraits ont significativement causé plus de répulsion que l’eau distillée et l’insecticide chimique. Les tests ont révélé un potentiel plus répulsif des extraits de feuilles comparé à celui des amandes. Les extraits de neem pourraient constituer une alternative crédible à la lutte chimique pour la protection de la patate douce contre ce charançon. English title: Evaluation of the repellent effect of neem extracts (Azadirachta indica A. Juss., 1830) on the sweet potato weevil (Cylas puncticollis Boheman, 1833) under laboratory conditions in Korhogo, northern Côte d’Ivoire Abstract An integrated pest management strategy for sweet potatoes has been developed to reduce pest losses. Thus, the repellent properties of neem leaf and kernel extracts were evaluated on Cylas puncticollis, a sweet potato weevil. For this purpose, four concentrations of extracts were prepared with four replicates per concentration. The test consisted of determining the percentage of weevils in the treated area. Each of the extract concentrations was applied to half of a blotting paper placed in 9 cm diameter Petri dishes on which 10 weevils were placed. The repellent effects of the extracts were compared to those of a chemical insecticide and distilled water. Test with 20 cL/L leaf extract caused 85% repellence compared to 45% for almonds at 25 g/L. Compared to the chemical insecticide and distilled water, the extracts caused significantly more repellence. The tests revealed a higher repellent potential of the leaf extracts compared to those of almonds. Neem extracts could be a credible alternative to chemical control for the protection of sweet potato against this weevil. Keywords: Neem extracts, Repellent effect, Sweet potato, Cylas puncticolli

Physicochemical and Nutritional Properties of Varieties of Carrot (Daucus carota) grown in Region of Korhogo, North of Côte d’Ivoire

Very popular for its therapeutic and nutritional virtues, culture of carrot (Daucus carota) has developed in temperate zones of Asia and Europe but also in some tropical regions of Africa including Côte d'Ivoire. Agronomic factors, commercial and food requirements require selection of varieties with good nutritional values. In this study, physicochemical properties and nutritional values of four carrot varieties namely Amazonia, Bahia, Madona and Pamela+ were compared after cultivation and harvest in region of Korhogo. Results showed that, Amazonia, the control carrot variety stands out for its acidity and minerals levels. Bahia is the richest variety with high levels of carbohydrate and protein. Madona is the most basic, wettest and fatest carrot. For a long storage, Pamela is most interesting variety. To our knowledge, it is the first time that physicochemical and nutritional parameters of carrot varieties in region of Korhogo have been studied. Future research on these carrot varieties will be studied of their post-harvest conservation, their sensory analysis and their transformation

Effets de la couverture des cages flottantes et de la période de distribution de l\'aliment sur la survie et la croissance des alevins du poisson-chat africain Heterobranchus longifilis Valenciennes 1840 en élevage intensif

L\'influence du recouvrement des cages flottantes par des bâches plastiques noires non transparentes et de la période (jour ou nuit) de distribution de l\'aliment sur la survie et la croissance du poisson-chat africain Heterobranchus longifilis a été évaluée. L\'expérience a consisté à observer le jour et la nuit des alevins nourris en quatre repas, dans deux types de cages flottantes : cages couvertes et cages non couvertes. Quelle que soit la période de distribution de l\'aliment, les meilleurs taux de survie ont été observés dans les cages couvertes (73,0 ± 2,6 % le jour et 75,0 ± 1,7 % la nuit contre 64,0 ± 3,5 % le jour et 67,0 ± 2,0 % la nuit). Les poids moyens finaux des poissons enregistrés dans ces cages sont de 16,9 ± 1,9 g le jour et 17,8 ± 1,9 g la nuit. Ces poids sont comparables à ceux observés dans les cages non couvertes avec distribution nocturne de l\'aliment (16,8 ± 1,1 g). Ces résultats montrent qu\'en cages couvertes, la période de distribution de l\'aliment n\'a aucune influence sur la croissance des poissons.The effects of covering the breeding floating cages with a black plastic canvas and the feeding period (day or night) on the survival and growth of the african cat-fish Heterobranchus longifilis have been investigated. Juvenile individuals of this species fed four times during daytime and nighttime were reared in two types of floating cages : covered with black plastic canvas and without any canvas. Whatever the feeding period, the best survival rates were recorded in covered cages (73,0 ± 2,6 % for daytime and 75,0 ± 1,7 % for nighttime, against 64,0 ± 3,5 % for daytime and 67,0 ± 2,0 % for nighttime). In these cages, final mean weights of fishes recorded were 16,9 ± 1,9 g for daytime and 17,8 ± 1,9 g for nighttime. These data were similar to those recorded in non covered floating cage with nighttime feeding. Results suggest that there is no effect of the feeding period on the growth of H. longifilis reared in cages with canvas. Keywords: Heterobranchus longifilis, alevinage, cage flottante, éclairement, horaires de nourrissage./Heterobranchus longifilis, fry rearing, floating cage, light, feeding time.Sciences & Nature Vol. 4 (1) 2007: pp. 85-9

Sustaining control of Schistosomiasis mansoni in western Côte d'Ivoire : results from a SCORE study, one year after initial praziquantel administration

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has launched several large-scale trials to determine the best strategies for gaining and sustaining control of schistosomiasis and transitioning toward elimination. In Côte d'Ivoire, a 5-year cluster-randomized trial is being implemented in 75 schools to sustain the control of schistosomiasis mansoni. We report Schistosoma mansoni infection levels in children one year after the initial school-based treatment (SBT) with praziquantel and compare with baseline results to determine the effect of the intervention.; The baseline cross-sectional survey was conducted in late 2011/early 2012 and the first follow-up in May 2013. Three consecutive stool samples were collected from 9- to 12-year-old children in 75 schools at baseline and 50 schools at follow-up. Stool samples were subjected to duplicate Kato-Katz thick smears. Directly observed treatment (DOT) coverage of the SBT was assessed and the prevalence and intensity of S. mansoni infection compared between baseline and follow-up.; The S. mansoni prevalence in the 75 schools surveyed at baseline was 22.1% (95% confidence interval (CI): 19.5-24.4%). The DOT coverage was 84.2%. In the 50 schools surveyed at baseline and one year after treatment, the overall prevalence of S. mansoni infection decreased significantly from 19.7% (95% CI: 18.5-20.8%) to 12.8% (95% CI: 11.9-13.8%), while the arithmetic mean S. mansoni eggs per gram of stool (EPG) among infected children slightly increased from 92.2 EPG (95% CI: 79.2-105.3 EPG) to 109.3 EPG (95% CI: 82.7-135.9 EPG). In two of the 50 schools, the prevalence increased significantly, despite a DOT coverage of >75%.; One year after the initial SBT, the S. mansoni prevalence had decreased. Despite this positive trend, an increase was observed in some schools. Moreover, the infection intensity among S. mansoni-infected children was slightly higher at the 1-year follow-up compared to the baseline situation. Our results emphasize the heterogeneity of transmission dynamics and provide a benchmark for the future yearly follow-up surveys of this multi-year SCORE intervention study

Impacts des rejets accidentels sur la qualité environnementale des sédiments de la rade portuaire d’Abidjan (lagune Ebrié ; Côte d’Ivoire)

La densité du trafic maritime s’est intensifié depuis la création du port d’Abidjan situé dans l’estuaire de la lagune Ebrié en Côte d’Ivoire. En outre sa rade portuaire est le lieu de rejets industriels et urbains. Les sédiments de la rade portuaire d’Abidjan, ont été analysés par spectrométrie d’adsorption en vue de déterminer les teneurs en éléments traces métalliques (ETM), afin d’évaluer le facteur d’enrichissement et la qualité du sédiment. Les sédiments de ce fond lagunaire ne sont pas pollués en Cd, et sont de bonne qualité environnementale. Leur teneur en Pb ne constitue pas de danger pour le biota. La pollution en Cr, Ni et Cu est modéré et les sédiments sont de mauvaises qualité. Concernant l’arsenic et le zinc, les échantillons dont le facteur d’enrichissement est inférieur à 1,3 ne constituent pas de danger pour l’environnement. Pour le reste des échantillons, l’arsenic (As) fortement enrichis, présente un danger pour les sédiments. Il en est de même pour Pb.Mots clés : ETM; Facteur d’enrichissement, qualité environnementale, rade portuaire, Abidjan, Côte d’Ivoir

Investigation et riposte à une épidémie de poliovirus sauvage à Kinshasa

Introduction: La République Démocratique du Congo a été considérée comme un pays à circulation rétablie de poliovirus sauvage (PVS). Cet article décrit l'épidémie de PVS qui a sévit dans la province de Kinshasa de 2010 à 2011. Méthodes: Les analyses ont porté sur les cas de paralysie flasque aigüe (PFA) enregistrés de décembre 2010 à décembre 2011, les données de surveillance des PFA, les données de couverture vaccinale et celles du monitorage indépendant des activités de vaccination supplémentaires. Résultats: Entre décembre 2010 à décembre 2011, 298 cas de PFA ont été enregistrés par les zones de santé parmi lesquels 34 cas de PVS confirmés. 58% des cas de PVS avaient plus de 15 ans avec plus d'hommes que de femmes. 10 passages d'activités de vaccination supplémentaires ont été mis en oeuvre dont 4 avaient ciblé toute la population de Kinshasa. Il n'y a plus eu de cas de PVS après le 3e passage. Le monitorage des activités de vaccination a montré une  proportion de sujets non vaccinés allant de 4 à 13%. La performance du système de surveillance était globalement bonne. Conclusion: La prédominance des adultes parmi les cas notifiés traduit leur susceptibilité alors qu'ils ne sont généralement pas concernés lors des campagnes de vaccination supplémentaires. Ceci devrait engager les autorités sanitaires à envisager des activités vaccinales supplémentaires ciblant les adultes afin de casser plus rapidement la chaîne de transmission. Les faiblesses subsistant dans le système de surveillance pourraient être jugulées par le renforcement de la surveillance à base communautaire.Key words: Paralysie flasque aigüe, poliovirus sauvage, épidémie, vaccination, République Démocratique du Cong