Improving urban drainage in Abidjan, Côte d’Ivoire

Tropical humid climates of sub-Saharan Africa with a high level of variability build a challenge for hygienic models used in urban drainage. Global models of urban drainage used in this region – for example the Caquot’s rate-of-flow model – are based on the parameters of Montana’s rain model. This model indicates the evolution of the maximum rainfall intensity according to the duration and the return period. In Côte d’Ivoire, several studies highlighted that adapting Montana’s rain model is not satisfactory for particular time slots, which in turn affects urban drainage calculations. This work aims at optimising and designing models which best simulate tropical downpours and improving calculations related to urban drainage in Abidjan and in other urban settings with similar climatic conditions. Various statistical processing undertaken showed that the rainfall distribution in the area of Abidjan is in line with the laws of Gumbel (10 – 30 mn rainfall) and Galton (45 – 240 mn rainfall). Including the data in mathematical conversion formulas made it possible to optimise Montana’s parameters and to design a new model that best simulates downpours in Abidjan. In addition, analysis of the Nicholson index revealed a drop in rainfall in Abidjan with a cyclical evolution ( about 17 year period), alternating dry, normal and wet periods. The new model is relevant since it overlaps two very satisfactory models and could be used to improve urban drainage calculations in Abidjan and similar climatic conditions.Keywords Abidjan; climatic variability; Montana’s model; sub-Saharan African tropical wet region; urban drainag

Analyse de la situation de l’environnement sanitaire des quartiers défavorisés dans le tissu urbain de Yopougon a Abidjan, Côte d’Ivoire

La combinaison, d’informations multi-sources (image QUICKBIRD, données exogènes, résultats d’enquêtes socio-environnementales) dans un système d’information géographique (SIG), a permis d’analyser l'environnement sanitaire de 6 quartiers précaires situés le long d'un canal d'évacuation des eaux à Yopougon, (Abidjan, Côte d’Ivoire). L’analyse et la cartographie des principaux facteurs relatifs à la qualité de vie des populations, permettent de constituer un observatoire de l’environnement sanitaire de ces milieux défavorisés. La finesse spatiale de l’image QUICKBIRD a contribuée à la mise à jour de la carte du mode d’occupation du sol. L’analyse des différents facteurs caractérisant l’environnement sanitaire révèle de nombreuses insuffisances dans le système de gestion de l’assainissement des quartiers précaires, exposant ainsi les populations aux maladies liées à l’assainissement telles que le paludisme et la diarrhée. Les résultats permettront de planifier et de valider les mesures à prendre pour remédier aux déficits d’assainissement dans ces milieux précaires.The integration into a Geographical information system (GIS) of multi-source data from QUICKBIRD imagery, ancilliary data and the results from socio-environmental investigations alowed to analyse the sanitary environment of 6 precarious settlements located along an open and exposed drainage channel, in Yopougon (Abidjan, Côte d’Ivoire). The observatory of the sanitary environment of these deprivileged areas were conducted through analysis and mapping of main factors influencing the life quality of the populations. The spatial sharpness of QUICKBIRD imagery contributed to update the land use/land cover map. Analysis of various factors witch characterise the sanitary environment reveals many insufficiences as regards the management of the sanitation system of the settlements, thus exposing the populations to illness related to sanitation like malaria and diarrhoea. The findings will permit planing appropriate measurements to overcome sanitation problems in these précarious areas

Comparative Analysis Of The Mapping Of The Vulnerability To Pollution Of Fissured Aquifers In Agboville Department By Drastic And SI Methods (South-East Of Côte d'Ivoire)

The study aims to establish vulnerability maps of groundwater pollution in Agboville department due to anthropogenic pressures, with a view to their sustainable management. The methods used are DRASTIC and SI. They use four common vulnerability parameters (groundwater depth, recharge, aquifer materials and topography) that are intrinsic to the aquifer. To these parameters, the DRASTIC method associates three others (soil type, unsaturated zone and hydraulic conductivity), while the SI method associates a fifth extrinsic parameter (land use). Their thematic mapping, followed by their combination in a GIS, made it possible to draw up the various pollution vulnerability maps using both methods. Each map highlights five classes of vulnerability. The dominant vulnerability classes in terms of surface area occupied are: low (32%) and high (36%) for the DRASTIC method, and medium (42%) and high (26%) for the SI method. The superimposition of the map of spatial distribution of nitrate levels in groundwater with the established vulnerability maps shows that the areas with low levels coincide with the low vulnerability classes, thus allowing their validation. The results of the Kappa test and the surface analysis to examine the vulnerability maps reveal that the Kappa coefficient (K = 0.29) is reliable and gave a fair agreement between the two methods. This agreement is confirmed by the surface analysis (45,25 %). The SI method appears to be the most appropriate for assessing the vulnerability to groundwater pollution in this area

Are schoolchildren less infected if they have good knowledge about parasitic worms? A case study from rural Côte d'Ivoire

Background: Parasitic worms (helminths) are common infections in low- and middle-income countries. For most helminth species, school-aged children are at highest risk of infection and morbidity, such as impaired cognitive and physical development. Preventive chemotherapy is the current mainstay for helminthiases control. Sanitation improvement and hygiene-related education are important complementary strategies, which act by altering children’s behaviour. However, little is known about the effect of improved knowledge on the risk of helminth infection. The aim of this study was to assess the potential influence of knowledge that children acquired at home or in school, without any specific health education intervention, on helminth infections. Methods: In May 2014, we conducted a cross-sectional survey in western Côte d’Ivoire. A total of 2498 children, aged 9-12 years, were subjected to three consecutive stool examinations using duplicate Kato-Katz thick smears to determine infections with soil-transmitted helminths and Schistosoma mansoni. Additionally, children were interviewed to assess their knowledge about helminth infections. Four knowledge scores were constructed by factor analysis; one, reflecting general knowledge about helminths and three manifesting helminth species-specific knowledge. The effect of general and specific knowledge on children’s helminth infection status was determined using meta-analysis. Results: Children who scored high in the hookworm-specific knowledge were less likely to be infected with hookworm but no association was found for the other helminth species. Moreover, greater general knowledge was not associated with lower odds of being infected with any helminth species. Most of the children interviewed believed that the effect of preventive chemotherapy is permanent, and hence, re-treatment is not necessary. Conclusions: Specific knowledge about different types of helminths might not suffice to induce behavioural change which in turn reduces infection and reinfection with helminths. Health education interventions should strive to strengthen the perception of risk and to clarify the true benefit of preventive chemotherapy.publishersversionpublishe

Effect of an integrated intervention package of preventive chemotherapy, community-led total sanitation and health education on the prevalence of helminth and intestinal protozoa infections in Côte d'Ivoire

Preventive chemotherapy with donated anthelminthic drugs is the cornerstone for the control of helminthiases. However, reinfection can occur rapidly in the absence of clean water and sanitation coupled with unhygienic behaviour. The purpose of this study was to assess the effect of an integrated package of interventions, consisting of preventive chemotherapy, community-led total sanitation (CLTS) and health education, on the prevalence of helminth and intestinal protozoa infections and on participants' knowledge, attitude, practice and beliefs (KAPB) towards these diseases including water, sanitation and hygiene (WASH).; A cross-sectional survey was carried out in nine communities of south-central Côte d'Ivoire to assess people's infection with helminths and intestinal protozoa and KAPB. Subsequently, interventions were targeted to five communities, while the remaining communities served as control. The intervention encouraged latrine construction and an evaluation was done 6-7 months later to determine open defecation status of the respective communities. Anthelminthic treatment was provided to all community members. A follow-up cross-sectional survey was conducted approximately one year later, using the same procedures.; Overall, 810 people had complete baseline and follow-up data and were given anthelminthic treatment. The baseline prevalence of hookworm, Schistosoma haematobium, Trichuris trichiura, Schistosoma mansoni and Ascaris lumbricoides was 31.1%, 7.0%, 2.0%, 1.0% and 0.3%, respectively. Four of the five intervention communities were classified open-defecation free. For hookworm infection, we observed higher negative changes in terms of proportion of decrease (-0.10; 95% confidence interval (CI): - 0.16, -0.04) and higher egg reduction rate (64.9 vs 15.2%) when comparing intervention with control communities. For intestinal protozoa, prevalence reduction was higher in intervention compared to control communities (8.2 vs 2.6%) and WASH indicators and intervention outcomes associated with lower odds for infection at follow-up. The intervention significantly impacted on reported latrine use (before: 15.5%, after: 94.6%), open defecation in the community surroundings (before: 75.0%, after: 16.7%) and awareness for environmental contamination through open defecation (before: 20.4%, after: 52.2%).; An integrated package of interventions consisting of preventive chemotherapy, health education and CLTS reduces the prevalence of helminth and intestinal protozoa infection. Additional studies in other social-ecological settings are warranted to confirm our findings

Epidemiology of intestinal parasite infections in three departments of south-central Côte d’Ivoire before the implementation of a cluster-randomised trial

Hundreds of millions of people are infected with helminths and intestinal protozoa, particularly children in low- and middle-income countries. Preventive chemotherapy is the main strategy to control helminthiases. However, rapid re-infection occurs in settings where there is a lack of clean water, sanitation and hygiene. In August and September 2014, we conducted a cross-sectional epidemiological survey in 56 communities of three departments of south-central Côte d’Ivoire. Study participants were invited to provide stool and urine samples. Stool samples were examined for helminth and intestinal protozoa infections using the Kato-Katz technique and a formalin-ether concentration method. Urine samples were subjected to a filtration method for the diagnosis of Schistosoma haematobium. Information on sociodemographic characteristics, knowledge, attitude, practices and beliefs with regard to hygiene, sanitation and intestinal parasitic diseases were collected using a questionnaire administered to household heads. Multivariable logistic regression models were employed to analyse associations between parasite infections and risk factors. Overall, 4,305 participants had complete parasitological and questionnaire data. Hookworm was the predominant helminth species (21.2%), while Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni and S. haematobium showed prevalences below 10%. Infections with pathogenic intestinal protozoa (e.g. Entamoeba histolytica/E. dispar and Giardia intestinalis) were similarly prevalent in the three departments. Hookworm infection was associated with open defecation and participants' age and sex. Entamoeba coli infection was negatively associated with the use of tap water at home (odds ratio (OR) = 0.66; p = 0.032). Disposal of garbage in close proximity to people’s home was positively associated with G. intestinalis (OR = 1.30; p = 0.015). Taken together, helminth and intestinal protozoa infections affected a considerable proportion of rural dwellers in south-central Côte d’Ivoire at the onset of a cluster-randomised intervention trial. Our results will serve as baseline to monitor the effect of a package of interventions, including preventive chemotherapy, sanitation and health education on re-infection with helminths and intestinal protozoa

Are schoolchildren less infected if they have good knowledge about parasitic worms? A case study from rural Côte d'Ivoire

Parasitic worms (helminths) are common infections in low- and middle-income countries. For most helminth species, school-aged children are at highest risk of infection and morbidity, such as impaired cognitive and physical development. Preventive chemotherapy is the current mainstay for helminthiases control. Sanitation improvement and hygiene-related education are important complementary strategies, which act by altering children's behaviour. However, little is known about the effect of improved knowledge on the risk of helminth infection. The aim of this study was to assess the potential influence of knowledge that children acquired at home or in school, without any specific health education intervention, on helminth infections.; In May 2014, we conducted a cross-sectional survey in western Côte d'Ivoire. A total of 2498 children, aged 9-12 years, were subjected to three consecutive stool examinations using duplicate Kato-Katz thick smears to determine infections with soil-transmitted helminths and Schistosoma mansoni. Additionally, children were interviewed to assess their knowledge about helminth infections. Four knowledge scores were constructed by factor analysis; one, reflecting general knowledge about helminths and three manifesting helminth species-specific knowledge. The effect of general and specific knowledge on children's helminth infection status was determined using meta-analysis.; Children who scored high in the hookworm-specific knowledge were less likely to be infected with hookworm but no association was found for the other helminth species. Moreover, greater general knowledge was not associated with lower odds of being infected with any helminth species. Most of the children interviewed believed that the effect of preventive chemotherapy is permanent, and hence, re-treatment is not necessary.; Specific knowledge about different types of helminths might not suffice to induce behavioural change which in turn reduces infection and reinfection with helminths. Health education interventions should strive to strengthen the perception of risk and to clarify the true benefit of preventive chemotherapy

Activites de transport terrestre et risques sanitaires dans la ville de San-Pedro (Cote d’Ivoire)

Les activités de transport terrestre sont fondamentales dans le processus de la mondialisation. Leurs développements engendrent la pollution, les accidents de la route et surtout les maladies professionnelles. Du fait de la croissance vertigineuse du parc automobile ivoirien, de l’âge des véhicules et de leur état technique précaire, beaucoup de polluants sont rejetés par la circulation automobile. Ceux-ci influencent le milieu physique et humain. Les activités de transport provoquent l’externalité négative. Cette étude vise à identifier les différents risques encourus par les transporteurs à San-Pedro. La recherche documentaire et l’enquête de terrain constituent les techniques de collecte des données et des informations utilisées. Les résultats montrent que les conséquences majeures de la pollution touchent la santé publique et l’écologie. En effet les nuisances sonores sont le quotidien de la ville de San-Pedro. Les riverains des routes, de l’aéroport, du port et des zones industrielles sont confrontés aux risques sanitaires. L’impact des transports sur la santé est également lié à l’âge des personnes et des modes de transport utilisés. Les accidents de la route endeuillent aussi les familles et font plusieurs blessés. En effet, 35% des personnes de plus de 65 ans sont exposées aux pathologies liées à la pollution de l’air et l’on enregistre plus de 400 accidents par ans à San-Pedro. De même, 65% des conducteurs risquent des Troubles Musculo Squelettiques. English title: Land transport activities and health risks in the city of San-Pedro (Cote d’Ivoire)  Abstract: Land transport activities are fundamental in the globalization process. Their developments generate pollution, road accidents and especially occupational diseases. Due to the dizzying growth of the Ivorian vehicle fleet, the age of the vehicles and their precarious technical condition, many pollutants are released by automobile traffic. These influence the physical and human environment. Transport activities cause the negative externality. This study aims to identify the different risks incurred by transporters in San-Pedro. Documentary research and field survey are the data and information collection techniques used. The results show that the major consequences of pollution affect public health and ecology. Indeed, noise pollution is the daily life of the city of San-Pedro. Residents of roads, the airport, the port and industrial areas face health risks. The impact of transport on health is also linked to the age of people and the modes of transport used. Road accidents also mourn families and cause many injuries. Indeed, 35% of people over 65 are exposed to pathologies linked to air pollution and more than 400 accidents are recorded per year in San-Pedro. Similarly, 65% of drivers risk Musculoskeletal Disorders. Keywords: Côte d’Ivoire, transport, risks, patholog

Using a New Approach to Design Innovative Tools for Monitoring and Evaluating Water Policy of Burkina Faso in Response to Climate Risks

Climate change impacts on water resources have jeopardized human security in the Sahel countries for many decades, especially in achieving food security. Many strategies and policies have been made to address such impacts. However, there are still difficulties to measure progress and the effectiveness of these policies and strategies with regard to climate risks. The lack of practical and consensual monitoring tool is one of the factors that can explain gaps in policies and initiatives to overcome these impacts. To move towards filling this gap, using ClimProspect model and a participatory approach, and based on in-depth vulnerability analysis, this paper makes available some innovative integrated and coherent resilience indicators and a new index for Burkina Faso’s water resources. Taking into account both climate and disaster risks, the indicators and index developed are related to warning, responses, recovery and long term resilience. The indicators-based index applied to three sites shows that agriculture water is less resilient to a changing climate with a score varying from 22.66% to 24%. These tools can help in formulating, implementation and reviewing water policy to secure water resources under the stress of climate change. The approach and findings bring together, on one hand, social and ecological resilience to climate risks, and sciences and policy on the other

Étude de postes et adaptation d'un système de gestion du personnel en Côte d'Ivoire

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