Ibrahima Sy

Absence of dry season Plasmodium parasitaemia, but high rates of reported acute respiratory infection and diarrhoea in preschool-aged children in Kaédi, southern Mauritania

BackgroundThe 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.MethodsWe 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.FindingsNo 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.ConclusionsMalaria 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.

Recours aux soins et utilisation des services de santé à Nouakchott (Mauritanie) : inégalités spatiales ou pesanteurs sociales ?

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.

Association between Childhood Diarrhoeal Incidence and Climatic Factors in Urban and Rural Settings in the Health District of Mbour, Senegal

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.

Prévalence des diarrhées infantojuvéniles dans deux districts de Nouakchott (Mauritanie) en 2008 : analyse de l’influence de l’hygiène du milieu

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.

Water, Sanitation and Diarrhoeal Diseases in Nouakchott (Mauritania): Analysing the Determinant of Urban Health Inequalities

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.

Urbanisation and its effect on risk factors associated with childhood diarrhoea in Mbour, Senegal : a visualisation

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.