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Backgrond: The Sahelian zone of Senegal is marked by heatwave events due to temperatures increase especially in 2013 exceeding 45 ° C with an impact on morbidity and mortality rise. In order to document health impacts of recurrent extreme temperatures in this part of the country, a study was carried out combining heatwaves detection, occurrence of climate-sensitive diseases and risk factors for exposure.Methods: To do this, a set of climatic (temperatures) and health (morbidity, mortality) data were collected for April, May and June season from 2009 to 2019. These data were complemented by surveys on exposure risk factors of 1246 households. Statistical methods were used to carry out univariate and bivariate analyzes while cartographic techniques allowed visualization of the main climatic and health indicators.Results: The results show an increase in temperatures compared to seasonal normal for the 1971-2000 reference period with threshold exceedances of the 90th percentiles (42°C) for the maxima and (27°C) the minima and higher temperatures during the months of May and June. From health perspective, it was noted an increase in cases of consultation on health facilities as well as a rise in declared morbidity by households especially in the departments of Kanel (17.7%), Ranérou (16.1 %), Matam (13.7%) and Bakel (13.7%). The heatwaves of May 2013 were also associated with cases of death with a reported mortality (observed by medical staff) of 12.4% unevenly distributed according to the departments with a higher number of deaths in Matam (25, 2%) and in Bakel (23.5%) than in Podor (8.4%) and Kanel (0.8%). The morbidity and mortality distribution according to gender shows that women (57%) were more affected than men (43%). These health risks have been associated with a number of factors including age, access to drinkable water, type of fuel, type of housing and construction materials, existence of fan, an air conditioner, health antecedents, etc.Conclusion: The heatwaves recurrence has led to an upsurge in certain diseases sensitive to rising temperatures, which is increasingly a public health issue in the Sahelian zone of Senegal.

The Sahelian zone of Senegal experienced heat waves in the previous decades, such as 2013, 2016 and 2018 that were characterised by temperatures exceeding 45°C for up to 3 successive days. The health impacts of these heat waves are not yet analysed in Senegal although their negative effects have been shown in many countries. This study analyses the health impacts of observed extreme temperatures in the Sahelian zone of the country, focusing on morbidity and mortality by combining data from station observation, climate model projections, and household survey to investigate heat wave detection, occurrence of climate-sensitive diseases and risk factors for exposure. To do this, a set of climatic (temperatures) and health (morbidity, mortality) data were collected for the months of April, May and June from 2009 to 2019. These data have been completed with 1246 households' surveys on risk factor exposure. Statistical methods were used to carry out univariate and bivariate analyses while cartographic techniques allowed mapping of the main climatic and health indicators. The results show an increase in temperatures compared to seasonal normal for the 1971-2000 reference period with threshold exceedances of the 90th percentiles (42°C) for the maxima and (27°C) the minima and higher temperatures during the months of May and June. From health perspective, it was noted an increase in cases of consultation in health facilities as well as a rise in declared morbidity by households especially in the departments of Kanel (17.7%), Ranérou (16.1 %), Matam (13.7%) and Bakel (13.7%). The heat waves of May 2013 were also associated with cases of death with a reported mortality (observed by medical staff) of 12.4% unequally distributed according to the departments with a higher number of deaths in Matam (25, 2%) and in Bakel (23.5%) than in Podor (8.4%) and Kanel (0.8%). The morbidity and mortality distribution according to gender shows that women (57%) were more affected than men (43%). These health risks have been associated with a number of factors including age, access to drinkable water, type of fuel, type of housing and construction materials, existence of fan and an air conditioner, and health history.The heat wave recurrence has led to a frequency in certain diseases sensitive to rising temperatures, which is increasingly a public health issue in the Sahelian zone of Senegal.

Backgrond: The Sahelian zone of Senegal is marked by heatwave events due to temperatures increase especially in 2013 exceeding 45 ° C with an impact on morbidity and mortality rise. In order to document health impacts of recurrent extreme temperatures in this part of the country, a study was carried out combining heatwaves detection, occurrence of climate-sensitive diseases and risk factors for exposure. Methods To do this, a set of climatic (temperatures) and health (morbidity, mortality) data were collected for April, May and June season from 2009 to 2019. These data were complemented by surveys on exposure risk factors of 1246 households. Statistical methods were used to carry out univariate and bivariate analyzes while cartographic techniques allowed visualization of the main climatic and health indicators. Results The results show an increase in temperatures compared to seasonal normal for the 1971-2000 reference period with threshold exceedances of the 90th percentiles (42°C) for the maxima and (27°C) the minima and higher temperatures during the months of May and June. From health perspective, it was noted an increase in cases of consultation on health facilities as well as a rise in declared morbidity by households especially in the departments of Kanel (17.7%), Ranérou (16.1%), Matam (13.7%) and Bakel (13.7%). The heatwaves of May 2013 were also associated with cases of death with a reported mortality (observed by medical staff) of 12.4% unevenly distributed according to the departments with a higher number of deaths in Matam (25, 2%) and in Bakel (23.5%) than in Podor (8.4%) and Kanel (0.8%). The morbidity and mortality distribution according to gender shows that women (57%) were more affected than men (43%). These health risks have been associated with a number of factors including age, access to drinkable water, type of fuel, type of housing and construction materials, existence of fan, an air conditioner, health antecedents, etc. Conclusion The heatwaves recurrence has led to an upsurge in certain diseases sensitive to rising temperatures, which is increasingly a public health issue in the Sahelian zone of Senegal.

Dans un contexte de villes sénégalaises confrontées à des problèmes d’assainissement, la ville de Rufisque fait face à un problème de santé publique à l’instar d’une insalubrité croissance exposant les populations au syndrome diarrhéique. L’objectif de cette étude est de mesurer la prévalence de la diarrhée chez les enfants de moins de 5 ans. Afin d’établir le lien entre la qualité de l’environnement et la diarrhée infanto-juvénile, un receuil des données sanitaires et une enquête ont été réalisés auprès de 918 ménages sur les conditions socio-environnementales et la morbidité diarrhéique en septembre 2018. Avec l’appui des méthodes statistiques uni-variées et bi-variées, il a été effectué des tests d’association (Khi-2) et de corrélation R de Pearson entre la morbidité diarrhéique et les facteurs de risque potentiels. Les résultats mettent en évidence une variabilité socio-spatiale des maladies diarrhéiques dans l’espace urbain, avec certains quartiers très touchés (Cartor, Gouye Aldiana, Colobane et Escale) et d’autres moins affectés (Hlm, Diokoul, et Rufisque II). Toutefois, cette distribution inégale de la pathologie diarrhéique est infleuncée par un certain nombre de facteurs de risque dont les plus significativement associés à sa survenue sont le mode d’accès à l’eau potable dont le robinet (R = 0,93), le WC branché à une fosse (R = 0,96), l’aire de jeu des enfants dans la cour (R = 0, 99) et dans les espaces péridomestiques (R = 0,81) ainsi que le statut socio-économique (R=0,94). Ces facteurs de risque diarrhéique laisse supposer que les enfants vivant dans des milieux urbains bien assainis sont moins exposés à l’occurrence des maladies diarrhéiques et vice-versa. Mots-clès : environnment, diarrhée, risque, prévalence, ville, Rufisque. English Abstract: Urban environment and health risk: Geographical approach to childhood diarrhoea in the city of Rufisque (Senegal). In a context of Senegalese cities facing sanitation problems, the city of Rufisque faces a public health problem such as growing insalubrity exposing populations to diarrheal syndrome. The objective of this study is to measure the prevalence of diarrhea in children under 5 years old. In order to establish the link between the quality of the environment and infant and juvenile diarrhea, a collection of health data and a survey were carried out among 918 households on socio-environmental conditions and diarrheal morbidity in September 2018. With Supporting univariate and bivariate statistical methods, Pearson association (Chi-square) and R correlation tests were performed between diarrheal morbidity and potential risk factors. The results highlight a socio-spatial variability of diarrheal diseases in urban areas, with some neighborhoods very affected (Cartor, Gouye Aldiana, Colobane and Escale) and others less affected (Hlm, Diokoul, and Rufisque II). However, this uneven distribution of diarrheal pathology is influenced by a number of risk factors, the most significantly associated with its occurrence are the mode of access to drinking water including the tap (R = 0.93), WC connected to a pit (R = 0.96), the children's play area in the yard (R = 0, 99) and in peridomestic spaces (R = 0.81) as well as the socio-economic status ( R = 0.94). These diarrheal risk factors suggest that children living in healthy urban settings are less exposed to the occurrence of diarrheal diseases and vice versa. Keywords: environment, diarrhea, risk, prevalence, city, Rufisque

Schistosomiasis is widely distributed along the Senegal River Basin (SRB), affecting both the human population and their livestock. Damming of the Senegal River for irrigation purposes in the 1980s induced ecological changes that resulted in a large outbreak of Schistosoma mansoni, followed a few years later by an increase and spread of Schistosoma haematobium infections. The presence of hybrid crosses between the human and cattle schistosomes, S. haematobium and Schistosoma bovis, respectively, is adding complexity to the disease epidemiology in this area, and questions the strength of the species boundary between these two species. This study aimed to investigate the epidemiology of S. haematobium, S. bovis and their hybrids along the Senegal River basin using both microsatellite genetic markers and analysis of mitochondrial and nuclear DNA markers. Human schistosome populations with a S. haematobium cox1 mtDNA profile and those with a S. bovis cox1 mtDNA profile (the so-called hybrids) appear to belong to a single randomly mating population, strongly differentiated from the pure S. bovis found in cattle. These results suggest that, in northern Senegal, a strong species boundary persists between human and cattle schistosome species and there is no prolific admixing of the populations. In addition, we found that in the SRB S. haematobium was spatially more differentiated in comparison to S. mansoni. This may be related either to the presence and susceptibility of the intermediate snail hosts, or to the colonisation history of the parasite. (C) 2019 Published by Elsevier Ltd on behalf of Australian Society for Parasitology.

West African cities face critical societal challenges that are linked to environmental and health changes. These challenges are further exacerbated by urbanization dynamics, climate change, socio-economic mutation and lack of capacity for sustainable urban development, governance and basic services delivery. The deficiency of environmental sanitation and ecosystem services have led to high complexity of urban health risks inequalities, resulting in the need for more research on efficient urban health policies. The purpose of this contribution is to present the main findings on the spatial epidemiology of diarrhaea and malaria, and their associated risks factors in the following select West African cities. Spatial variability of exposure to diarrhaea and malaria transmission is linked to several health risks such as lack of access to water and sanitation, solid wastes management, urban flooding, precarious housing conditions, urban agriculture, socio-economic status and social practices and individual behaviours fluctuating according to the specificity of urban areas. These factors and their interconnections make some groups (differentiated by geography) more vulnerable to poor outcomes due to limited capacity to effectively respond to health risks and poor performance by the health system. We demonstrate the potential for a spatial epidemiology perspective that disaggregates data to, clusters of houses, neighbourhood, sector and municipality scale to support health policies and interventions, and how these results can contribute to achieving SDG 3 (Health and Well-Being for all) in African urban areas.

The purpose of this article is to improve knowledge and understanding of the determinants of unemployment duration by gender in Cote d'Ivoire. One of the central questions on this issue is to what extent the personal characteristics of jobseekers affect their exit from unemployment. In this sense, we apply a proportional risk model with heterogeneity correction of Weibull (2004), applied to data from the Household Employment Survey in Cote d'Ivoire (EEMCI) that was conducted in 2012 by AGEPE. The results of the study reveal that young men are much more likely to exit unemployment than young women. Even if the results show a negative relationship between high level of education and unemployment, the high representation of women on the unemployment rate remains attributable to their very low level of education and the weight of tradition relegating the role of the woman, as a matter of priority, to housework.

Climate services have been criticised in the past for their tendency to only disseminate results from climate research, rather than to seek to understand and tailor to the needs of their target audiences. Two surveys have been conducted within two projects, ISIpedia and CLIMAP, to assess users’ needs for climate and climate impacts information of all countries (with a foremost focus on West Africa) and for Senegal. The joint analysis of the results showed that climate and climate-impact information is very relevant for West African respondents’ activities but a number of barriers prevent existing climate services from fully fulfilling the role they could play in this respect. Consistently across both surveys, the respondents highlighted the irrelevance or the incompleteness of the information that current climate services provide, which is mostly related to the lack of high-resolution information or high uncertainties, as the biggest barriers. Both surveys showed that the lack of training to understand the provided information is also an important barrier, which calls for the organisation of capacity-building activities to ensure the uptake of the information by their target audiences. Overall, the survey responses demonstrated the importance of stakeholder engagement to ensure the usefulness of climate services in West Africa. In addition, appropriate integration of the existing climate services within the national contexts as well as their dissemination within the ecosystem of information portals and products appear to be essential to ensure their effectiveness.

Introduction : L’eau potable et l’assainissement constituent deux facteurs de sante publique lies de maniere inextricable surtout dans la ville de Nouakchott ou l’insuffisance de ces services conduit a une multitude de recours et de pratiques d’hygiene mettant en jeu un systeme socio-ecologique complexe avec un risque accru de transmission de maladies hydriques (diarrhee, cholera, etc.).Methodes : Ainsi, cette contribution analyse l’impact du systeme socio-ecologique sur le developpement des maladies diarrheiques par une utilisation de donnees socio-environnementales et epidemiologique provenant de sources diverses (enquetes nationales et registres de consultation).Resultats : Dans l’ensemble, les resultats montrent que seuls 25,6 % des menages ont acces a des sources d’eau potable tandis que 69,8 % des habitants disposent de latrines ameliorees. Les conditions environnementales expliquent le niveau de la morbidite diarrheique qui se situe a 12,8 % a l’echelle urbaine avec une distribution spatiale inegale montrant des communes moins touchees comme Tevragh Zeina (9,1 %) et des municipalites plus affectees comme Sebkha (19,1 %). La distribution selon les categories d’âge montre que les enfants de moins de cinq ans sont les plus affectes (51,7 %) suivis des personnes âgees de plus de 14 ans (34,2 %). L’analyse de correlation entre les variables socio-economiques, environnementales et epidemiologiques revele un certain nombre d’associations significatives : consommation d’eau non traitee et diarrhee (R = 0,429) ; collection d’eaux usees et survenue de diarrhee ; existence de latrine amelioree et reduction du risque diarrheique (R = 0,402).Discussion : Des lors, l’exposition aux maladies diarrheiques a travers le prisme de l’eau et de l’assainissement pose un veritable probleme de sante publique qui requiert une approche systemique et integree pour ameliorer l’hygiene du milieu.

French Abstract: Plusieurs mois apres l’arrivee de la covid-19 et la fermeture des classes en Afrique Subsaharienne francophone, la situation epidemiologique n’est pas toujours sous controle. Hormis la perte de revenu des employes du secteur educatif prive, la fermeture prolongee des classes apparait comme un prejudice pour les apprenants et pourrait negativement impacter le developpement a long terme. A cet effet, nous menons une reflexion sur les conditions d’une ouverture des ecoles afin que le remede ne soit pas pire que le virus. Sur la base de la modelisation des series chronologiques interrompues, nous montrons que l’ouverture totale ou partielle des classes ne se traduit pas necessairement par une augmentation du taux de croissance du nombre de cas confirmes de covid-19 dans les pays de l’echantillon. Ce resultat montre que si les mesures barrieres sont respectees dans les ecoles, les autorites devraient ouvrir les classes, meme quand le pic de l’epidemie n’est pas encore atteint. English Abstract: Several months after the arrival of covid-19 and the closure of classes in French-speaking Sub-Saharan Africa, the epidemiological situation is not always under control. Apart from the loss of income of employees in the private education sector, the prolonged closure of classes appears to be detrimental to learners and could negatively impact long-term development. To this end, we are conducting a reflection on the conditions for opening schools so that the remedy is not worse than the virus. Based on the modeling of the interrupted time series, we show that the full or partial opening of classes does not necessarily translate into an increase in the growth rate of the number of confirmed cases of covid-19 in the countries in the sample. This result shows that if the barrier measures are respected in schools, the authorities should open the classes, even when the peak of the epidemic has not yet been reached.

The liberalization of the telecommunications sector in Togo aimed at ensuring access to a better quality of telecommunication services at affordable prices to everyone. While the liberalization policy has increased competition in the sector and reduced significantly telecommunication services prices charged to costumers, statistics on the access and use of telecommunication services in Togo reveal disparities with respect to individuals' socio-economic characteristics which could be an indication of the existence of inequalities of opportunities in the access and use of these services. This paper investigates the inequalities of opportunity in the access and use of telecommunication services in Togo using a parametric approach. The results of estimations indicate that, inequalities of opportunities are larger for men and the elderly than respectively women and youths and are more pronounced in urban areas and regions such as the Plateaux and Savanna regions. Moreover, the circumstance variables such as the ‘place of residence’ and the ‘region’ are the key variables in explaining the inequalities of opportunities in the access and use of telecommunication services in Togo. So, policies toward reducing inequalities of opportunity in the access and use of telecommunication services in Togo should be designed with regards to men, the elderly, and people living in urban areas and regions such as the Plateaux and Savanna regions.

Background Schistosomiasis is a water-based disease transmitted by trematodes belonging to the genus Schistosoma. The aim of this study was to assess the relationship between the prevalence of schistosomiasis and access to water, sanitation and hygiene (WASH) and environmental and socioeconomic factors in the city of Korhogo, northern Côte d'Ivoire. Methods A cross-sectional study including 728 randomly selected households was conducted in Korhogo in March 2015. The heads of the households were interviewed about access to WASH and environmental and socioeconomic factors. All children abed between 5 and 15 years living in the households were selected to provide stool and urine samples for parasitological diagnosis of Schistosoma mansoni and Schistosoma haematobium infection. The relationship between infection with S. mansoni and potential risk factors was analysed by a mixed logistic regression model with ‘household’ as a random factor. Likelihood ratio tests were used to identify factors that were significantly associated with a Schistosoma spp. infection. Results The overall prevalence of schistosomiasis among school-aged children in Korhogo was 1.9% (45/2341) composed of 0.3% (3/1248) S. haematobium and 3.5% (42/1202) S. mansoni. Due to the low prevalence of S. haematobium infection, risk factor analysis was limited to S. mansoni. Boys were 7.8 times more likely to be infected with S. mansoni than girls. Children between 10 and 15 years of age were 3.8 times more likely to be infected than their younger counterparts aged 5-10 years. Moreover, living in a house further away from a water access point (odds ratio [OR] = 0.29, 95% confidence interval [CI]: 0.13–0.70) and abstaining from swimming in open freshwater bodies (OR = 0.16, 95% CI: 0.04–0.56) were significantly associated with decreased odds of S. mansoni infection. The socioeconomic status did not appear to influence the prevalence of S. mansoni. Conclusions A strategy to reduce the incidence of schistosomiasis should focus on health education to change the behaviour of populations at risk and encourage communities to improve sanitation and infrastructure in order to reduce contact with surface water. Electronic supplementary material The online version of this article (10.1186/s40249-018-0431-6) contains supplementary material, which is available to authorized users.

L’acces a une eau potable en quantite suffisante represente un enjeu majeur de sante publique dans une ville sahelienne semi-aride a l’instar de Nouakchott en Mauritanie ou le faible taux de raccordement des menages au reseau d’adduction conduit a une multitude de recours et pratiques avec un risque de contamination de l’eau et de propagation de maladies hydriques (diarrhee, cholera, typhoide, parasitoses, dermatoses, etc.). Ainsi, ce papier cherche a analyser l’impact de la qualite de l’eau sur les inegalites de risques sanitaires en milieu urbain. Pour ce faire, l’approche methodologique combine une demarche socioenvironnementale, microbiologique et epidemiologique basee sur l’utilisation de sources de donnees diverses (enquetes nationales, etudes bacteriologiques de l’eau et morbidite diarrheique diagnostiquee). Dans l’ensemble, les resultats montrent que seuls 25,6% des menages disposent de sources d’approvisionnement ameliorees en eau potable au moment ou une majeure partie de la population a recours a des modes d’alimentation precaires avec une dotation journaliere inferieure a la norme recommandee de 20 litres par personne. Les analyses bacteriologiques montrent que 93% des points d’eau qui alimentent environ 74% des menages sont contamines avec des valeurs comprises entre 10 et 80 coliformes fecaux par 100 ml d’eau. Ce degre de contamination corrobore avec le niveau de prevalence de la diarrhee (12,8%) dont la morbidite se revele aussi inegale que la variabilite des modes d’approvisionnement et de la qualite microbiologique de l’eau selon les communes. Des lors, l’exposition aux maladies diarrheiques a travers le prisme de l’eau pose un veritable probleme de sante publique. Il s’avere indispensable de developper une strategie axee sur la sensibilisation, l’amenagement des points d’eau et le traitement avant la consommation pour ameliorer la qualite de l’eau a tous les niveaux de la chaine d’approvisionnement.

Drinking water and sanitation are two factors of inter-linked inextricably public health especially in the city of Nouakchott where the low availability of these services leads to a multitude of use and hygiene practices involving a complex socio-ecological system with an increased risk of waterborne diseases transmission (diarrhea, cholera, etc.).Thus, this contribution analyzes the impact of socio-ecological system on the development of diarrheal diseases by using socio-environmental and epidemiological data from various sources (national surveys and registries consultation).Overall, the results show that only 25.6% of households have access to drinking water sources while 69.8% of the populations dispose improved latrines. Hence, the weakness in environmental sanitation conditions explains the level of diarrheal morbidity averring 12.8% at the urban level, with an unequal spatial distribution showing less affected communes such as Tevragh Zeina (9.1%) and municipalities more affected like Sebkha (19.1%). The distribution according to the age categories shows that children under 5 years are the most affected with 51.7% followed by people aged over 14 with 34.2%. The correlation analysis between socio-economic, environmental and epidemiological variables reveals a number of significant associations: untreated water consumption and diarrhea (R = 0.429); collection of wastewater and occurrence of diarrhea ; existence of improved latrine and reduction of diarrheal risk (R = 0.402).Therefore, exposure to diarrheal diseases through the prism of water and sanitation is a real public health problem that requires a systemic and integrated approach to improving environmental health.

Since the 1970s, the northern part of Cote d'Ivoire has experienced considerable fluctuation in its meteorology including a general decrease of rainfall and increase of temperature from 1970 to 2000, a slight increase of rainfall since 2000, a severe drought in 2004-2005 and flooding in 2006-2007. Such changing climate patterns might affect the transmission of malaria. The purpose of this study was to analyze climate and environmental parameters associated with malaria transmission in Korhogo, a city in northern Cote d'Ivoire. All data were collected over a 10-year period (2004-2013). Rainfall, temperature and Normalized Difference Vegetation Index (NDVI) were the climate and environmental variables considered. Association between these variables and clinical malaria data was determined, using negative binomial regression models. From 2004 to 2013, there was an increase in the annual average precipitation (1100.3-1376.5 mm) and the average temperature (27.2°C-27.5°C). The NDVI decreased from 0.42 to 0.40. We observed a strong seasonality in these climatic variables, which resembled the seasonality in clinical malaria. An incremental increase of 10 mm of monthly precipitation was, on average, associated with a 1% (95% Confidence interval (CI): 0.7 to 1.2%) and a 1.2% (95% CI: 0.9 to 1.5%) increase in the number of clinical malaria episodes one and two months later respectively. A 1°C increase in average monthly temperature was, on average, associated with a decline of a 3.5% (95% CI: 0.1 to 6.7%) in clinical malaria episodes. A 0.1 unit increase in monthly NDVI was associated with a 7.3% (95% CI: 0.8 to 14.1%) increase in the monthly malaria count. There was a similar increase for the preceding-month lag (6.7% (95% CI: 2.3% to 11.2%)). The study results can be used to establish a malaria early warning system in Korhogo to prepare for outbreaks of malaria, which would increase community resilience no matter the magnitude and pattern of climate change.

Multilingual abstracts in the six official working languages of the United Nations. (PDF 594 kb)

Rapid urbanisation, particularly in secondary cities in Africa, brings along specific challenges for global health, including the prevention and control of infectious diseases such as diarrhoea. Our purpose was to visualise urbanisation trends and its effect on risk factors associated with childhood diarrhoea, e.g. water supply, sanitation, wastewater and solid waste management in Mbour, a secondary city in south-western Senegal. Our visualisation is facilitated by epidemiological and geographical surveys carried out in 2016. A deeper spatial and visual understanding of the urbanisation trends and the disparities of diarrhoea-associated risk factors might lead to the implementation of suitable health interventions and preventive measures. Our visualisation is aimed to serve as a basis for discussion and as a decision support tool for policymakers, municipal officials and local communities to prioritise interventions related to water, sanitation and waste management with a view to reduce the environmental and health risks in the rapidly growing city of Mbour, which is set as an example for other similar secondary cities across low- and middle-income countries in Africa.

Land Use Land-Cover Change (LULCC), such as deforestation, affects the climate system and land-atmosphere interactions. Using simulations carried out within the LUCID (Land Use and Climate, IDentification of robust Impacts) project framework, we first quantify the role of historical land-cover change induced by human activities on surface climate in West Africa. Focusing on two contrasted African regions, we find that climate responses of land-use changes are small but they are still statistically significant. In Western Sahel, a statistically significant near-surface atmospheric cooling and a decrease in water recycling are simulated in summer in response to LULCC. Over the Guinean zone, models simulate a significant decrease in precipitation and water recycling in autumn in response to LULCC. This signal is comparable in magnitude with the effect induced by the increase in greenhouse gases. Simulated climate changes due to historical LULCC could however be underestimated because: (i) the prescribed LULCC can be underestimated in those regions; (ii) the climate models underestimate the coupling strength between West African surface climate and leaf area index (LAI) and (iii) the lack of interactive LAI in some models. Finally, our study reveals indirect atmospheric processes triggered by LULCC. Over the Western Sahel, models reveal that a significant decrease in solar reflection tend to cool down the surface and thus counteract the atmospheric feedback. Conversely, over the Guinea zone, models reveal that the indirect atmospheric processes and turbulent heat fluxes dominate the climatic responses over the direct effects of LULCC.

The analysis of the spatial and temporal variability of climate parameters is crucial to study the impact of climate-sensitive vector-borne diseases such as malaria. The use of malaria models is an alternative way of producing potential malaria historical data for Senegal due to the lack of reliable observations for malaria outbreaks over a long time period. Consequently, here we use the Liverpool Malaria Model (LMM), driven by different climatic datasets, in order to study and validate simulated malaria parameters over Senegal. The findings confirm that the risk of malaria transmission is mainly linked to climate variables such as rainfall and temperature as well as specific landscape characteristics. For the whole of Senegal, a lag of two months is generally observed between the peak of rainfall in August and the maximum number of reported malaria cases in October. The malaria transmission season usually takes place from September to November, corresponding to the second peak of temperature occurring in October. Observed malaria data from the Programme National de Lutte contre le Paludisme (PNLP, National Malaria control Programme in Senegal) and outputs from the meteorological data used in this study were compared. The malaria model outputs present some consistencies with observed malaria dynamics over Senegal, and further allow the exploration of simulations performed with reanalysis data sets over a longer time period. The simulated malaria risk significantly decreased during the 1970s and 1980s over Senegal. This result is consistent with the observed decrease of malaria vectors and malaria cases reported by field entomologists and clinicians in the literature. The main differences between model outputs and observations regard amplitude, but can be related not only to reanalysis deficiencies but also to other environmental and socio-economic factors that are not included in this mechanistic malaria model framework. The present study can be considered as a validation of the reliability of reanalysis to be used as inputs for the calculation of malaria parameters in the Sahel using dynamical malaria models, This study was funded by the Erasmus Mundus Action 2 Strand 1 Lot-15 (ACP) program. The authors would like also to thank the Department of Meteorology, Faculty of Physics, at the Universidad Complutense de Madrid (UCM) who welcomed Ibrahima and partly supported special issues, mainly during his stay in July 2014 within the framework of the cooperation project VR 63/12 between LPAOSF-UCAD (Dakar) and UCM (Madrid), and also within the framework of the XII Convocatoria UCM de Cooperación al Desarrollo and the I-COOP Project ICOOP-202024B. The QWeCI Project funded by the European Commission Seventh Framework Research Programme under the grant agreement 243964 is also greatly acknowledged. The research was partly funded by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Emerging and Zoonotic Infections at the University of Liverpool in partnership with Public Health England (PHE) and Liverpool School of Tropical Medicine (LSTM). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, the Department of Health or Public Health England. Cyril Caminade was also supported by The Farr Institute for Health Informatics Research (MRC grant: MR/M0501633/1).

We assessed the association between childhood diarrhoeal incidence and climatic factors in rural and urban settings in the health district of Mbour in western Senegal. We used monthly diarrhoeal case records among children under five years registered in 24 health facilities over a four-year period (2011–2014). Climatic data (i.e., daily temperature, night temperature and rainfall) for the same four-year period were obtained. We performed a negative binomial regression model to establish the relationship between monthly diarrhoeal incidence and climatic factors of the same and the previous month. There were two annual peaks in diarrhoeal incidence: one during the cold dry season and one during the rainy season. We observed a positive association between diarrhoeal incidence and high average temperature of 36 °C and above and high cumulative monthly rainfall at 57 mm and above. The association between diarrhoeal incidence and temperature was stronger in rural compared to urban settings, while higher rainfall was associated with higher diarrhoeal incidence in the urban settings. Concluding, this study identified significant health–climate interactions and calls for effective preventive measures in the health district of Mbour. Particular attention should be paid to urban settings where diarrhoea was most common in order to reduce the high incidence in the context of climatic variability, which is expected to increase in urban areas in the face of global warming.

Background Diarrhoeal diseases remain an important cause of mortality and morbidity among children, particularly in low- and middle-income countries. In Senegal, diarrhoea is responsible for 15% of all deaths in children under the age of five and is the third leading cause of childhood deaths. For targeted planning and implementation of prevention strategies, a context-specific understanding of the determinants of diarrhoeal diseases is needed. The aim of this study was to identify risk factors of diarrhoeal diseases in children under the age of five in Mbour, Senegal. Methods Between February and March 2014, a cross-sectional survey was conducted in four zones of Mbour to estimate the burden of diarrhoeal diseases (i.e. diarrhoea episodes in the 2 weeks preceding the survey) and associated risk factors. The zones covered urban central, peri-central, north peripheral and south peripheral areas. Overall, 596 households were surveyed by a questionnaire, yielding information on sociodemographic, environmental and hygiene behavioural factors. Univariable and multivariable logistic regression analyses were used to identify risk factors associated with the occurrence of diarrhoea. Results The reported prevalence of diarrhoea among children under the age of five during the 2 weeks preceding the survey was 26%. Without adjustment, the highest diarrhoea prevalence rates were observed in the peri-central (44.8%) and urban central zones (36.3%). Multivariable regression revealed significant associations between diarrhoeal diseases and unemployment of mothers (adjusted odds ratio [aOR] = 1.62, 95% confidence interval [CI]: 1.18–2.23), use of open bags for storing household waste (aOR = 1.75, 95% CI: 1.00–3.02), evacuation of household waste in public streets (aOR = 2.07, 95% CI: 1.20–3.55), no treatment of stored drinking water (aOR = 1.69, 95% CI: 1.11–2.56) and use of shared toilets (aOR = 1.69, 95% CI: 1.11–2.56). Conclusion We found a high prevalence of diarrhoea in children under the age of five in Mbour, with the highest prevalence occurring in the central and peri-central areas. These findings underscore the need for public health interventions to alleviate the burden of diarrhoea among vulnerable groups. Promotion of solid waste disposal and reduction of wastewater exposure should be implemented without delay. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0323-1) contains supplementary material, which is available to authorized users.

The lowest access to water and sanitation services in the city of Nouakchott leads to several practices and behaviours that create a social-ecological system which increasing risk of waterborne diseases transmission like diarrhoea. Using environmental, socio-economic and epidemiologic indicators from national statistic services, this study aims to assess the impact of Nouakchott’s social-ecological system on diarrhoeal diseases with particular emphasize on vulnerability to environmental health risks according to water and sanitation status. The results showed that respectively 25.6% and 69.8% of households had access to improved water sources and latrines with a large variability according to municipalities. The diarrhoeal morbidity (12.8%) was higher in dense urban areas where the lack of water supply and sanitation facilities affected mainly poor households (20.8% of the population). However, diarrhoeal risk is spatially variable in accordance to environmental sanitation disparities with a rate rising from 9.1% in municipalities with high level of improved water and latrines to 19.1% in communities with a lower level of ecosystem services. The correlation analysis between socio-economic, environmental and epidemiological variables reveals significant associations. Thus, the dynamic of social-ecological system demonstrated that environmental factors linked to unimproved drinking Water sources and sanitation services were the main driver of diarrhoeal diseases transmission in some municipalities. The reality of the linkage between health risks due to diarrhoea and urban environmental conditions addresses the issues of the Sustainable Development Goals (SDG) Health and Wellbeing and Water and Sanitation services in Mauritania context.

This article offers an analysis of poverty using a set of dimensions not yet explored particularly oriented on “the poverty felt. Poverty is measured here, not in relation to a standard or predefined threshold of income or expenditure, or based on criterions of welfare quantifiable, but through the perception that households have, themselves, of their socioeconomic situation (the household self-assesses poor or not). On this basis, we propose an econometric analysis to determine the factors which condition the subjective evaluation of the households of their standard of living, in Senegal in 2006. Besides the traditional factors (age, sex, environment (urban or rural) of residence and educational level of the head of the household), factors as the district of residence of household's head, the policies implemented by the State received by the household and the extent of corruption in the community, appear largely explained the poverty felt in Senegal.

In urban areas in Nouakchott, diarrheal diseases present a major public health problem, especially for children and adolescents. In August, 2008, a cross-sectional survey of 300 households in two adjacent districts of the city sought to study correlations between diarrheal disease and environmental health. The results show that 87 children of all ages had about 139 episodes of diarrhea, for an average prevalence of 14.8% that varied by age (23.6% in children younger than 5 years and 9.7% among children aged 5 to 14 years) and area (16.8% in Tevragh-Zeina and 28.3% in Sebkha). The univariate analysis indicates that 52% of the diarrhea risk was due to precarious basic hygiene. Studies of the specific causes of diarrheal diseases to help improve their treatment are necessary to supplement these epidemiological results.

Confrontee a un probleme d’assainissement, Rufisque a servi de cadre d’analyse des interactions entre insalubrite et sante a travers une focalisation sur la morbidite urbaine analysee avec des donnees epidemiologiques collectees aupres des menages et des centres de sante. La morbidite diarrheique tres elevee connait une variation spatio-temporelle. De plus, l’essentiel des pathologies diagnostiquees serait lie au deficit d’hygiene. Ainsi, ces tendances montrent que Rufisque souffre de son manque d’assainissement. Toutefois, les mobilisations citadines en faveur d’une meilleure qualite environnementale tendent a modifier cette structure du risque diarrheique.

Une enquete epidemiologique a ete menee au Senegal oriental – district de Kedougou – dans le but d’etablir la prevalence des bilharzioses intestinale et urinaire chez les enfants d’âge scolaire de 6 a 14 ans. Cinquante-trois villages et hameaux sont concernes soit 3324 enfants. Pour l’etude statistique, on procede, dans chaque village, au tirage au sort d’un enfant sur trois dont les selles et les urines sont analysees. La prevalence globale est alors de 47 %. Une campagne de traitement de masse par praziquantel de tous les enfants de 6 a 14 ans, scolarises ou non, a ete initiee en 2008 associee a des reunions d’information et de sensibilisation des villageois. Apres traitement, la prevalence globale est tombee a 6,9 % en 2009 puis a 3,7 % en 2010, montrant ainsi l’efficacite des sensibilisations et des latrines.

In African cities where environmental, social and economic problems facilitate the development of urban pathology, inadequate or ineffective health facilities raise the question of access to quality care, especially for slum dwellers. The city of Nouakchott marked by a multifaceted urban crisis is an illustration of this troubling situation. To analyse the spatial organisation and functioning of the healthcare system by assessing the use of health services, we studied this utilisation in August 2004 in three areas of the city by a cross-sectional survey of 836 households. The results show that therapeutic itineraries are as diverse as health care provision is varied. About 50.8 % of those seeking health care reported using modern services (public health clinics, private clinics, private doctors or nurses) for the most common diseases (acute respiratory infection and diarrhea) in their community, but this rate varied significantly by disease, social category and neighborhood. Thus, this mediocre level of utilisation of public health clinics is due to the poor quality of care provided. Moreover, healthcare services are often used only in case of severe or worsening illness, with signs (e.g., cough and persistent fever, or weight loss) seen to suggest more serious diseases, such as tuberculosis, meningitis or severe malaria. Geographic accessibility of health services was relatively good (70 %). It was the economic, socio-cultural, organizational and functional factors that appeared to determine the choice to use modern health care. The slackening of socio-cultural and organizational constraints and adaptation to economic ones should help to improve health policies and foster a functioning healthcare system.

Les maladies diarrheiques constituent la deuxieme cause de morbidite chez les enfants de moins de 5 ans en Afrique, au sud du Sahara et plus particulierement en Cote d’Ivoire. Un projet pilote de gestion des diarrhees par l’approche ecosante a ete initie en 2006 dans un village periurbain de la commune de Yopougon, a Abidjan. Apres plusieurs rencontres d’echange avec les populations et un atelier de lancement participatif incluant toutes les parties prenantes, une enquete menage transversale par questionnaire (n = 205) adressee aux femmes de menage, une enquete geographique, l’analyse d’eau de puits, des observations et des groupes de consultations (focus group) ont ete realises en aout 2006 afin de determiner la prevalence des maladies diarrheiques et d’identifier les facteurs de risques majeurs. 1234 personnes ont ete recensees dans les 205 menages. 7 % de ces personnes (85/1234) avaient vecu un episode diarrheique au cours des deux semaines precedant la date d’enquete. La tranche d’âge des moins de 5 ans etait la plus affectee avec une prevalence de 14 %, suivie de celle des plus de 15 ans (6 %) et enfin des enfants de 5 a 15 ans (3 %). Les principaux facteurs de risques identifies dans l’avenement des diarrhees sont, entre autres, le lieu de conservation de l’eau de boisson (P-value = 0,02), le recipient de conservation (p-value = 0,03) et le lieu d’installation des latrines dans les menages (p-value = 0,02). D’autres facteurs et comportements a risques ont ete egalement identifies. Il s’agit des enfants qui mangent sans se laver les mains, des mouches qui pullulent et couvrent les repas consommes, des poubelles sans fermeture et couvertes de mouches, de dechets solides et points d’eaux stagnantes qui couvrent toute la surface habitee du village. Ces resultats ont permis, a travers un processus transdisciplinaire et participatif incluant les communautes et autres parties prenantes, la mise en place d’actions de renforcement de capacites des villageois pour faire face aux maladies diarrheiques.

Background The epidemiology of malaria in the Senegal River Gorgol valley, southern Mauritania, requires particular attention in the face of ongoing and predicted environmental and climate changes. While “malaria cases” are reported in health facilities throughout the year, past and current climatic and ecological conditions do not favour transmission in the dry season (lack of rainfall and very high temperatures). Moreover, entomological investigations in neighbouring regions point to an absence of malaria transmission in mosquito vectors in the dry season. Because the clinical signs of malaria are non-specific and overlap with those of other diseases (e.g. acute respiratory infections and diarrhoea), new research is needed to better understand malaria transmission patterns in this region to improve adaptive, preventive and curative measures. Methods We conducted a multipurpose cross-sectional survey in the city of Kaédi in April 2011 (dry season), assessing three major disease patterns, including malaria. Plasmodium spp. parasite rates were tested among children aged 6–59 months who were recruited from a random selection of households using a rapid diagnostic test and microscopic examination of Giemsa-stained thick and thin blood films. Acute respiratory infection and diarrhoea were the two other diseases investigated, administering a parental questionnaire to determine the reported prevalence among participating children. Findings No Plasmodium infection was found in any of the 371 surveyed preschool-aged children using two different diagnostic methods. Acute respiratory infections and diarrhoea were reported in 43.4% and 35.0% of the participants, respectively. About two thirds of the children with acute respiratory infections and diarrhoea required medical follow-up by a health worker. Conclusions Malaria was absent in the present dry season survey in the capital of the Gorgol valley of Mauritania, while acute respiratory infections and diarrhea were highly prevalent. Surveys should be repeated towards the end of rainy season, which will enhance our understanding of the potential changes in malaria transmission in a region known as ‘hot spot’ of predicted climate change.

L’urbanisation non maîtrisée des villes africaines en déficit de services de gestion des déchets urbains génère des paysages qui deviennent des lieux d’interactions multiples et variées entre santé et environnement. Soumise à une forte croissance urbaine dans un contexte de sous-équipement en services d’assainissement, la ville de Nouakchott n’échappe pas à cette situation qui se traduit par la propagation de nombreuses pathologies posant ainsi de multiples problèmes de santé publique. Afin d’étudier les risques sanitaires auxquels s’exposent les populations, une enquête transversale a été menée en août 2004 auprès de 836 ménages dans trois quartiers de la ville. Les résultats de l’étude montrent les principaux problèmes de santé (syndrome du paludisme, syndrome de l’appareil respiratoire, syndrome l’appareil digestif) ressentis par les populations tout en mettant en évidence la prévalence des maladies les plus récurrentes dont les infections respiratoires aiguës (28,0 %) et les diarrhées (17,2 %) ainsi que les facteurs environnementaux d’exposition aux risques sanitaires. Ainsi, l’importance des maladies hygiéniques dans la morbidité globale montre que la ville présente des conditions écologiques favorables au développement de la pathologie urbaine. Le poids déterminant des conditions environnementales dans l’occurrence de ces pathologies permet de conforter les conceptions sur les liens entre santé et environnement. Par ailleurs, ces interactions traduisent l’incidence de la pauvreté urbaine très marquée dans les quartiers étudiés. Ces résultats appellent à une approche intégrée des questions de santé, d’environnement et de pauvreté dans les politiques de développement des villes., The uncontrolled urbanization in African cities with inadequate access to urban waste management services, generates landscapes that become places of multiple and varied interactions between health and environment. Subject to strong urban growth in a context of under-equipment in sanitation services, the city of Nouakchott is not an exception in this situation resulting in the spread of many diseases and leading to many public health problems. To investigate the health risks faced by populations, a cross-sectional survey was conducted in August 2004 among 836 households in three districts of the city. The study results show the major health problems (malaria syndrome, respiratory affections, and digestive troubles) experienced by people while highlighting the prevalence of the most recurrent diseases including acute respiratory infections (28.0 %) and diarrhea (17.2 %) and environmental factors of exposure to health risks. Thus, the importance of the hygienic diseases in global morbidity shows that the city presents ecological conditions favourable to the development of urban pathology. The decisive influence of environmental conditions in the occurrence of these diseases makes it possible to consolidate the common conceptions on the links between health and environment. Moreover, these interactions reflect the incidence of urban poverty very rampant in studied areas. These results call for an integrated approach to health, environment and poverty issues in the development policies of the cities.

In African cities where environmental, social and economic problems facilitate the development of urban pathology, inadequate or ineffective health facilities raise the question of access to quality care, especially for slum dwellers. The city of Nouakchott marked by a multifaceted urban crisis is an illustration of this troubling situation. To analyse the spatial organisation and functioning of the healthcare system by assessing the use of health services, we studied this utilisation in August 2004 in three areas of the city by a cross-sectional survey of 836 households. The results show that therapeutic itineraries are as diverse as health care provision is varied. About 50.8 % of those seeking health care reported using modern services (public health clinics, private clinics, private doctors or nurses) for the most common diseases (acute respiratory infection and diarrhea) in their community, but this rate varied significantly by disease, social category and neighborhood. Thus, this mediocre level of utilisation of public health clinics is due to the poor quality of care provided. Moreover, healthcare services are often used only in case of severe or worsening illness, with signs (e.g., cough and persistent fever, or weight loss) seen to suggest more serious diseases, such as tuberculosis, meningitis or severe malaria. Geographic accessibility of health services was relatively good (70 %). It was the economic, socio-cultural, organizational and functional factors that appeared to determine the choice to use modern health care. The slackening of socio-cultural and organizational constraints and adaptation to economic ones should help to improve health policies and foster a functioning healthcare system.

Potable water and sanitation facilities access constitutes one of the major problems faced by developing countries. In Senegal, more than 70% of urban centres lack drinking water distribution networks and satisfactory sewage systems. For this reason, public authorities have initiated series of institutional plans to strengthen the implementation of water and sanitation policies in various urban contexts as in the town of Rufisque. Geographical and epidemiological investigations were carried out from 2003 to 2005 to evaluate these policies impact in Rufisque. The goal was to assess health impact of various water supply and sewage management systems. Results show that operating different water supply and sewage management systems induces considerable variations on community’s sanitary, environmental, social, economic and political development. Despite of some progress made, many areas in the town still have difficulties to access to safe drinking water and to satisfactory sanitation services. The behaviours of the communities are still lacking the right changes. Spontaneous and growing urbanisation has increased the financial and other capacity shortfalls mainly at municipal levels. This paper makes an inventory of areas where these policies were implemented, and emphasizes the important role that scientific research would better have to play to reinforce their achievements.