Vulnerability and adaptation to climate change in the semi-arid regions of west Africa

The paper provides an overview of demographic and economic facts and trends in West Africa in general, and Ghana and Mali in particular, with country data snapshots. It examines the development dynamics in the semi-arid and dry sub-humid areas that comprise a significant portion of the West African drylands. Climate vulnerability in the West African context includes extensification of agriculture onto increasingly marginal drought-prone soils, reduced mobility of pastoralists, and the increasing prevalence of built structures to store river water. This increases sensitivity and exposure of downstream water users to low water levels and drought. The paper provides in-depth analysis and policy recommendations.Canada’s International Development Research Centre (IDRC)UK’s Department for International Development (DFID

Discrepant Prevalence and Incidence of Leishmania Infection between Two Neighboring Villages in Central Mali Based on Leishmanin Skin Test Surveys

Leishmaniasis is a vector-borne disease transmitted to humans by the bite of an infected sand fly. Leishmaniasis is present in more than 88 countries and affects more than 12 million people. Depending on the species of Leishmania, the host can develop cutaneous leishmaniasis (CL), which is characterized by skin ulcers in uncovered parts of the body or a more severe form, visceral leishmaniasis, which affects the liver and spleen and is fatal if not treated. This study aims to establish the past and present infection with Leishmania parasites in two villages where recent cases have been diagnosed by the dermatology center (CNAM) in Bamako. This was achieved using a Leishmania-specific skin test that was administered annually to permanent residents of Kemena and Sougoula villages from 2006 to 2008. The results show that transmission of Leishmania is active and stable in these two villages. Moreover, despite sharing similar cultural and environmental features, the individuals from Kemena presented three times the risk of Leishmania infection compared with those from Sougoula. Our findings raise awareness of the continued presence of CL in Mali

Seasonality and Prevalence of Leishmania major Infection in Phlebotomus duboscqi Neveu-Lemaire from Two Neighboring Villages in Central Mali

Phlebotomus duboscqi is the principle vector of Leishmania major, the causative agent of cutaneous leishmaniasis (CL), in West Africa and is the suspected vector in Mali. Although found throughout the country the seasonality and infection prevalence of P. duboscqi has not been established in Mali. We conducted a three year study in two neighboring villages, Kemena and Sougoula, in Central Mali, an area with a leishmanin skin test positivity of up to 45%. During the first year, we evaluated the overall diversity of sand flies. Of 18,595 flies collected, 12,952 (69%) belonged to 12 species of Sergentomyia and 5,643 (31%) to two species of the genus Phlebotomus, P. duboscqi and P. rodhaini. Of those, P. duboscqi was the most abundant, representing 99% of the collected Phlebotomus species. P. duboscqi was the primary sand fly collected inside dwellings, mostly by resting site collection. The seasonality and infection prevalence of P. duboscqi was monitored over two consecutive years. P. dubsocqi were collected throughout the year. Using a quasi-Poisson model we observed a significant annual (year 1 to year 2), seasonal (monthly) and village effect (Kemena versus Sougoula) on the number of collected P. duboscqi. The significant seasonal effect of the quasi-Poisson model reflects two seasonal collection peaks in May-July and October-November. The infection status of pooled P. duboscqi females was determined by PCR. The infection prevalence of pooled females, estimated using the maximum likelihood estimate of prevalence, was 2.7% in Kemena and Sougoula. Based on the PCR product size, L. major was identified as the only species found in flies from the two villages. This was confirmed by sequence alignment of a subset of PCR products from infected flies to known Leishmania species, incriminating P. duboscqi as the vector of CL in Mali

Vulnerability and adaptation to climate change in the semi-arid regions of West Africa

This series is based on work funded by Canada’s International Development Research Centre (IDRC) and the UK’s Department for International Development (DFID) through the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA).This report, which encompasses the findings of a Regional Diagnostic Study (RDS) for West Africa, was undertaken in 2014-15 to advance understanding of climate change in semi-arid regions of Africa and Asia. The RDS represents the first phase of a research effort under the Adaptation at Scale in Semi-Arid Regions (ASSAR) project. ASSAR is one of four consortia generating new knowledge of climate change hotspots under the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA1). The ASSAR project operates in Western, Eastern and Southern Africa and Western India. The ASSAR focal countries in Africa are Ghana, Mali, Ethiopia, Kenya, Botswana, and Namibia, and in India the focal states are Tamil Nadu, Maharashtra, and Karnataka

Additional file 1: of Impact of insecticide-treated bednets and indoor residual spraying in controlling populations of Phlebotomus duboscqi, the vector of Leishmania major in Central Mali

Table S1. Number of collected sand flies per household per month before and after IRS in the study area. Before IRS/LLINs, the number of collected flies per household ranged from 205 to 649 with a median of 293.00 and variance of 19778.94. After IRS/LLINs, the number of collected flies per household ranged from 25 to 159 with a median of 59.00 and variance of 3123.29. (DOCX 16 kb

Correction: Prevalence of Cutaneous Leishmaniasis in Districts of High and Low Endemicity in Mali.

[This corrects the article DOI: 10.1371/journal.pntd.0005141.]

Additional file 2: of Impact of insecticide-treated bednets and indoor residual spraying in controlling populations of Phlebotomus duboscqi, the vector of Leishmania major in Central Mali

Table S2. Meteorological information for the region of Segou, 2004 to 2017. (DOCX 19 kb

A cross-sectional study of the filarial and Leishmania co-endemicity in two ecologically distinct settings in Mali

Abstract Background Filariasis and leishmaniasis are two neglected tropical diseases in Mali. Due to distribution and associated clinical features, both diseases are of concern to public health. The goal of this study was to determine the prevalence of co-infection with filarial (Wuchereria bancrofti and Mansonella perstans) and Leishmania major parasites in two ecologically distinct areas of Mali, the Kolokani district (villages of Tieneguebougou and Bougoudiana) in North Sudan Savanna area, and the district of Kolondieba (village of Boundioba) in the South Sudan Savanna area. Methods The prevalence of co-infection (filarial and Leishmania) was measured based on (i) Mansonella perstans microfilaremia count and/or filariasis immunochromatographic test (ICT) for Wuchereria bancrofti-specific circulating antigen, and (ii) the prevalence of delayed type hypersensitivity (DTH) responses to Leishmania measured by leishmanin skin test (LST). Results In this study, a total of 930 volunteers between the age of 18 and 65 were included from the two endemic areas of Kolokani and Kolondieba. In general, in both areas, filarial infection was more prevalent than Leishmania infection with an overall prevalence of 15.27% (142/930) including 8.7% (81/930) for Mansonella perstans and 8% (74/930) for Wuchereria bancrofti-specific circulating antigen. The prevalence of Leishmania major infection was 7.7% (72/930) and was significantly higher in Tieneguebougou and Bougoudiana (15.05%; 64/425) than in Boundioba (2.04%; 8/505) (χ2 = 58.66, P < 0.0001). Among the filarial infected population, nearly 10% (14/142) were also positive for Leishmania with an overall prevalence of co-infection of 1.50% (14/930) varying from 2.82% (12/425) in Tieneguebougou and Bougoudiana to 0.39% (2/505) in Boundioba (P = 0.0048). Conclusion This study established the existence of co-endemicity of filarial and Leishmania infections in specific regions of Mali. Since both filarial and Leishmania infections are vector-borne with mosquitoes and sand flies as respective vectors, an integrated vector control approach should be considered in co-endemic areas. The effect of potential interaction between filarial and Leishmania parasites on the disease outcomes may be further studied