Sub-Saharan Africa / Afrique subsaharienne

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    Malaria transmission in relation to rice cultivation in the irrigated Sahel of Mali
    (Elsevier, 2003) Dolo, Guimogo; Briët, Olivier J.T.; Dao, Adama; Traoré, Sékou F.; Bouaré, Madama
    Seven cross-sectional entomological surveys were carried out from September 1995 to February 1998 in three irrigated rice growing villages and three villages without irrigated agriculture in the area surrounding Niono, located 350 km north-east of Bamako, Mali. The transmission pattern differed markedly between the two zones. In the irrigated zone, the transmission of malaria was fairly constant over the seasons at a low level. In the non-irrigated zone, transmission was mostly below detection level during the dry season, whereas it was high toward the end of the rainy season. In the irrigated zone, high densities of mosquitoes were correlated with low anthropophily, low sporozoite indices and probably low survival rates. In the non-irrigated zone, mosquito densities were lower and these relationships were less pronounced. Differential use of mosquito nets in the two zones may have been an important factor in the observed differences in transmission. The presence of cattle may also have played an important role. Two mosquito-catching methods (human landing catch and spray catch) were compared.
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    Assessment of research needs for public health adaptation to social, environmental and climate change impacts on vector-borne diseases in Africa : an informal expert consultation convened by the Special Programme for Research and Training in Tropical Diseases (TDR)
    (TDR/World Health Organization, Geneva, CH, 2012) World Health Organization; Thomson, Madeleine; Mantilla, Gilma; Platzer, Barbara; Willingham, Arve Lee
    Control strategies for vector--‐borne diseases (VBD) are a pillar of public health policies. Potential impacts of VBD-¬‐related risks reflect environmental exposure as well as social vulnerabilities, both of which are sensitive to climatic conditions. The existing evidence suggests that climate change impacts will substantially increase burdens on those populations that are already vulnerable to climate extremes, such as those of the African continent. Climate change in Africa induces multiple threats to development and the social dimensions of climate change are, therefore, increasingly highlighted on the development agenda. This is of particular significance for drylands in sub-¬‐Saharan Africa, in which water-¬‐related VBD are a significant disease burden while these areas are, at the same time, particularly poor, food insecure, ecologically fragile and socially vulnerable. The gap in knowledge about the relationships between social and economic vulnerabilities and environmental hazards linked to VBD in a context of climatic change, and the even larger gap in policy options for addressing the situation, have been identified by African ministers of health and environment, and technical experts internationally, as serious obstacles to evidence-¬‐based health policy change. Capacities need to be strengthened for generating, interpreting and using socio-¬‐ economic, environmental, meteorological and other climate information that could guide VBD prevention and control strategies and improve the ability of African countries to adapt to and reduce the effects of these changes in ways that benefit the most vulnerable populations. Trans--‐disciplinary research-¬‐for-¬‐policy frameworks for improved VBD risk management need to be developed that can sustainably improve the resilience of African populations to such VBD-¬‐related health threats under climate change conditions. An informal expert consultation was held in Addis Ababa, Ethiopia, from 27-¬‐29 February 2012 to engage key stakeholders from the region in discussions to reach consensus on the most important research gaps and identify priorities in the African context for assessing impacts of interrelated social, environmental and climate changes on the relevant VBD burden of vulnerable populations as well as for developing and testing practical strategies for mitigating these impacts through adaptation.
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    Biodiversity of African vegetables
    (Earthscan, London, GB, 2009) Maundu, Patrick; Achigan-Dako, Enoch; Morimoto, Yasuyuki
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    Trans-disciplinary study on the health risks of cryptosporidiosis from dairy systems in Dagoretti, Nairobi, Kenya : study background and farming system characteristics
    (Springer, 2012-08) Kang’ethe, Erastus K.; Kimani, Violet N.; McDermott, Brigid; Grace, Delia; Lang’at, Alfred K.
    This paper characterises the dairy farming system in Dagoretti, Nairobi. Characterisation was part of a broader ecohealth project to estimate the prevalence and risk of cryptosporidiosis and develop risk mitigation strategies. In the project a trans-disciplinary team addressed epidemiological, socioeconomic, environmental and policy aspects of cryptosporidiosis, an emerging zoonosis. This paper also provides background and describes sampling methods for the wider project. Three hundred dairy households were probabilistically sampled from a sampling frame of all dairy households in five of the six locations of Dagoretti, one of the eight districts of Nairobi Province. Randomly selected households identified 100 non-dairy-keeping households who also took part in the study. A household questionnaire was developed, pre-tested and administered in the dry and wet seasons of 2006. An additional study on livelihood and economic benefits of dairying took place with 100 dairy farmers randomly selected from the 300 farms (as well as 40 non-dairy neighbours as a control group), and a risk targeted survey of environmental contamination with Cryptosporidium was conducted with 20 farmers randomly selected from the 29 farmers in the wider survey who were considered at high risk because of farming system. We found that around 1 in 80 urban households kept dairy cattle with an average of three cattle per household. Cross-breeds of exotic and local cattle predominate. Heads of dairykeeping households were significantly less educated than the heads of non-dairy neighbours, had lived in Dagoretti for significantly longer and had significantly larger households. There was a high turnover of 10 % of the cattle population in the 3-month period of the study. Cattle were zero grazed, but productivity parameters were sub-optimal as were hygiene and husbandry practices. In conclusion, dairy keeping is a minor activity in urban Nairobi but important to households involved and their community. Ecohealth approaches are well suited to tackling the complex problem of assessing and managing emerging zoonoses in urban settings.
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    Social and gender determinants of risk of cryptosporidiosis, an emerging zoonosis, in Dagoretti, Nairobi, Kenya
    (Springer, 2012-08) Kimani, Violet N.; Mitoko, Grace; McDermott, Brigid; Grace, Delia; Ambia, Julie
    The aim of the study was to investigate the social and gender determinants of the risk of exposure to Cryptosporidium fromurban dairying in Dagoretti, Nairobi. Focus group discussions were held in six locations to obtain qualitative information on risk of exposure. A repeated cross-sectional descriptive study included participatory assessment and household questionnaires (300 randomly selected urban dairy farming households and 100 non-dairying neighbours). Onehundred dairy households randomly selected from the 300 dairy households participated in an additional economic survey along with 40 neighbouring non-dairy households. We found that exposure to Cryptosporidium was influenced by gender, age and role in the household. Farm workers and people aged 50 to 65 years had most contact with cattle, and women had greater contact with raw milk. However, children had relatively higher consumption of raw milk than other age groups. Adult women had more daily contact with cattle faeces than adult men, and older women had more contact than older men. Employees had greater contact with cattle than other groups and cattle faeces, and most (77 %) were male. Women took more care of sick people and were more at risk from exposure by this route. Poverty did not affect the level of exposure to cattle but did decrease consumption of milk. There was no significant difference between men and women as regards levels of knowledge on symptoms of cryptosporidiosis infections or other zoonotic diseases associated with dairy farming. Awareness of cryptosporidiosis and its transmission increased significantly with rising levels of education. Members of nondairy households and children under the age of 12 years had significantly higher odds of reporting diarrhoea: gender, season and contact with cattle or cattle dung were not significantly linked with diarrhoea. In conclusion, social and gender factors are important determinants of exposure to zoonotic disease in Nairobi.
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    Prevalence of cryptosporidiosis in dairy cattle, cattle-keeping families, their non-cattle-keeping neighbours and HIV-positive individuals in Dagoretti Division, Nairobi, Kenya
    (Springer, 2012-08) Kange’the, Erastus; McDermott, Brigid; Grace, Delia; Mbae, Cecilia; Mulinge, Erastus
    This paper reports a study estimating the prevalence of cryptosporidiosis, an emerging zoonosis, in people and cattle in Dagoretti, Nairobi. A repeated cross-sectional survey was carried out among randomly selected cattle keepers in Dagoretti, their dairy cattle and their non-cattle-keeping neighbours in the dry and wet seasons of 2006. A survey was also carried out among a group of people living with human immunodeficiency virus (HIV). Faecal samples were examined for Cryptosporidium oocysts using the modified Ziehl–Neelsen method; 16 % of the samples were also examined using immunofluorescence antibody (IFA) technique. Quality control consisted of blind reviews of slides, examining split samples and confirming slide results with IFA. We found that members of dairy households had a dry season cryptosporidiosis prevalence of 4 % and wet season prevalence of 0.3 %, and non-dairy households, a prevalence of 5 and 0 %, respectively. The cattle dry season prevalence was 15 %, and the wet season prevalence, 11 %. The prevalence in people living with HIV was 5 %. The laboratory quality control system showed some inconsistency within and between different tests, indicating challenges in obtaining consistent results under difficult field and working conditions. In conclusion, this is the first reported study to simultaneously survey livestock, livestock keepers and their neighbours for cryptosporidiosis. We failed to find evidence that zoonotic cryptosporidiosis is important overall in this community. This study also draws attention to the importance of quality control and its reporting in surveys in developing countries.
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    Outcome mapping for fostering and measuring change in risk management behaviour among urban dairy farmers in Nairobi, Kenya
    (Springer, 2012-08) Nyangaga, Julius N.; Grace, Delia; Kimani, Violet; Kiragu, Monica W.; Langat, Alfred K.
    A study was undertaken to investigate and mitigate the risk from zoonotic Cryptosporidium associated with dairy farming in Dagoretti division, Nairobi, Kenya. Outcome mapping (OM), a relatively new tool for planning and evaluation, was used to foster and then monitor changes in farmer management of health risks. Elements of the OM framework, including the vision, mission and expected progress markers, were developed in participatory sessions and a set of progress markers was used for monitoring behaviour change in farmers participating in the project (the boundary partners). Behaviour change (the outcome challenge) was supported by a range of awareness and educational campaigns, working with strategic partners (extension agents and administrative leaders). The farmers the project worked with made considerable progress according to the markers; they demonstrated an understanding of cryptosporidiosis, established or maintained clean and well drained cattle sheds, and took conscious effort to reduce possible infection. Farmers who did not participate in the project (non-contact farmers) were found to be less advanced on the progress marker indicators. Non-contact farmers who carried out risk-reducing practices had done so independently of the project team. The administration leaders, as strategic partners, had a positive attitude towards the project and confidence in their ability to support project objectives. The study demonstrates the utility of OM in helping to identify and support behavioural change.
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    Multiple burdens of zoonotic disease and an ecohealth approach to their assessment
    (Springer, 2012-08) Grace, Delia; Gilbert, Jeff; Randolph, Thomas; Kang’ethe, Erastus
    Zoonoses occur at the interface of human and animal disease and partly because their impact and management fall across two sectors they are often neglected. The Global Burden of Disease captures the impact of zoonoses on human health in terms of disability-adjusted life years (DALYs). Based on this, we estimate that in low income countries, zoonoses and diseases which recently emerged from animals make up 26 % of the DALYs lost to infectious disease and 10 % of the total DALYs lost. In contrast, in high income countries, zoonoses and diseases recently which emerged from animals represent less than 1 % of DALYs lost to infectious disease and only 0.02 % of the total disease burden. We present a framework that captures the costs of zoonoses and emerging disease to human, animal and ecosystem health in terms of cost of treatment, cost of prevention, health burden and intangible and opportunity costs. We also discuss how ecohealth concepts of transdisciplinarity, participation and equity can help in assessing the importance of zoonoses in developing countries and illustrate these with an example of assessing milk-borne disease.
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    Development and delivery of evidence-based messages to reduce the risk of zoonoses in Nairobi, Kenya
    (Springer, 2012-08) Kang’ethe, Erastus; Kimani, Violet; Grace, Delia; Mitoko, Grace; McDermott, Brigid
    This paper describes a trans-disciplinary process of co-generating and disseminating evidence-based messages for reducing the risk from cryptosporidiosis and other zoonoses in an urban community in Nairobi. Research findings about disease prevalence, risk factors and observed risky and risk-mitigating practices were analysed by a team comprising researchers, community members and local policy- and decision-makers. Using participatory planning, multiple strategies were developed for disseminating key information. We identified five vulnerable groups at higher risk of exposure to cryptosporidiosis and other cattle zoonoses with similar transmission pathways (women, children, elderly people, immunosuppressed people and male farm workers). For each group, targeted messages were developed. Good practices already in use, as were also practices as practices to improve environmental conditions. These messages were disseminated through printed material, in a workshop, through community campaigners and also an edutainment soap opera episode broadcast on Kenyan television. In conclusion, a participatory and trans-disciplinary process can help transform the findings of research into messages that are targeted, attractive and understandable.
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    Evaluating a group-based intervention to improve the safety of meat in Bodija Market, Ibadan, Nigeria
    (Springer, 2012-08) Grace, Delia; Dipeolu, Morenike; Olawoye, Janice; Ojo, Ernest; Odebode, Stella
    We evaluated a group-based, participatory training intervention to improve food safety among meat processors and retailers in Bodija Market, Ibadan, Nigeria. An interactive training workshop was held for Butchers Associations’ representatives who were selected to pass on information and training to their group. Meat hygiene knowledge, attitude and practice was assessed before attending the workshop and afterwards (n063). It was also assessed for those who did not attend the workshop (n068) but were intended recipients of training through their association. Microbiological quality of meat was assessed before and after the workshop (n0400 samples). After the workshop, participants significantly improved knowledge, attitude and practice in key food safety aspects; specifically, understanding sources of contamination and food-borne diseases, use of bleach and disinfectant and hand washing. Participants also shared information with an average of 18 other group members and improvements were seen in group members who did not attend the workshop but received training through their Butchers Association.
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    Cryptosporidium species detected in calves and cattle in Dagoretti, Nairobi, Kenya
    (Springer, 2012-07) Kang’ethe, Erastus K.; Mulinge, Erastus K.; Skilton, Robert A.; Njahira, Moses; Monda, Joseph G.
    A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twentyfive samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.
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    Influence of gender and group membership on food safety : the case of meat sellers in Bodija market, Ibadan, Nigeria
    (Springer, 2012-08) Grace, Delia; Olowoye, Janice; Dipeolu, Morenike; Odebode, Stella; Randolph, Thomas
    We describe a study to assess the bacteriological quality and safety of meat in Bodija market in Ibadan and to investigate the influence of gender and group membership on food safety. Mixed methods were used to gather information on meat safety and related socioeconomic factors. These methods included a participatory urban appraisal, focus group discussions with eight butchers’ associations, in depth discussions with six key informants, a questionnaire study of 269 meat sellers and a cross-sectional survey of meat quality (200 samples from ten associations). We found that slaughter, processing and sale of beef meat take place under unhygienic conditions. The activities involve both men and women, with some task differentiation by gender. Meat sold by association members is of unacceptable quality. However, some groups have consistently better quality meat and this is positively correlated with the proportion of women members. Women also have significantly better food safety practice than men, though there was no significant difference in their knowledge of and attitude towards food safety. Most meat sellers (85 %) reported being ill in the last 2 weeks and 47 % reported experiencing gastrointestinal illness. Eating beef, eating chicken, eating offal, consuming one’s own products and belonging to a group with poor quality of meat were all strong and significant predictors of self-reported gastrointestinal illness.We include that gender and group membership influence meat quality and self reported gastrointestinal illness and that butchers’ associations are promising entry points for interventions to improve food safety.
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    Participatory and integrative approaches to food safety in developing country cities
    (Springer, 2012-08) Grace, Delia; Kang’ethe, Erastus; Waltner-Toews, David
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    Participatory probabilistic assessment of the risk to human health associated with cryptosporidiosis from urban dairying in Dagoretti, Nairobi, Kenya
    (Springer, 2012-08) Grace, Delia; Monda, Joseph; Karanja, Nancy; Randolph, Thomas F.; Kang’ethe, Erastus K.
    We carried out a participatory risk assessment to estimate the risk (negative consequences and their likelihood) from zoonotic Cryptosporidium originating in dairy farms in urban Dagoretti, Nairobi to dairy farm households and their neighbours.We selected 20 households at high risk for Cryptosporidium from a larger sample of 300 dairy households in Dagoretti based on risk factors present. We then conducted a participatory mapping of the flow of the hazard from its origin (cattle) to human potential victims. This showed three main exposure pathways (food and water borne, occupational and recreational). This was used to develop a fault tree model which we parameterised using information from the study and literature. A stochastic simulation was used to estimate the probability of exposure to zoonotic cryptosporidiosis originating from urban dairying. Around 6 % of environmental samples were positive for Cryptosporidium. Probability of exposure to Cryptosporidium from dairy cattle ranged from 0.0055 for people with clinical acquired immunodeficiency syndrome in non-dairy households to 0.0102 for children under 5 years from dairy households. Most of the estimated health burden was born by children. Although dairy cattle are the source of Cryptosporidium, the model suggests consumption of vegetables is a greater source of risk than consumption of milk. In conclusion, by combining participatory methods with quantitative microbial risk assessment, we were able to rapidly, and with appropriate ‘imprecision’, investigate health risk to communities from Cryptosporidium and identify the most vulnerable groups and the most risky practices.
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    Identifying Research Questions and Framework for Sub-Saharan Africa Countries - Authors' Meeting Proceedings
    (2012) The African Institute for Health & Development (AIHD)
    The Ecohealth Program is collaborating with the African Institute for Health & Development (AIHD) to coordinate the production of thematic papers on women’s health in agro-ecosystems. This paper provides a review of a collaborative meeting between researchers commissioned for project publications. Ten proposals / current projects are presented and critiqued with recommendations for revision, along with plenary comments. Feedback from the authors and reviewers indicated that they had found the meeting fruitful, providing a good basis upon which the authors would review their papers.
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    An Agroecosystem Health Case Study in the Central Highlands of Kenya
    (2008) Gitau, Thomas; Waltner-Toews, David; McDermott, John
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    One assumption, two observations and some guiding questions for the practice of agro-ecosystem health
    (2000) Waltner-Toews, D; Murray, T; Kay, J; Gitau, T; Raez-Luna, E
    The paper describes the features of agro-ecosystem health as a paradigm or framework to study and develop sustainable agricultural systems. It is posited that agro-ecosystem health research is undertaken in order to help people make better decisions with regard to managing the ecosystems in which they live and grow food. Agro-ecosystems can be viewed and interpreted from a variety of non-equivalent perspectives, and within each perspective, agro-ecosystems can be viewed and understood at different spatial and temporal scales. Therefore, whose perspective is taken into account in identification of constraints and priorities, and designing solutions will determine whether research and development efforts will lead to sustainable agricultural systems.
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    Agro-ecosystem health: Principles and methods used in high-potential tropical agro-ecosystem
    (2000) Gitau, T; McDermott, J J; Waltner-Toews, D; Gathuma, J M; Kang, E K
    The paper briefly describes the application of agro-ecosystem health framework for characterisation of an agro-ecosystem in central Kenya, and identification of the indications of its health. The lessons learnt from the application are briefly discussed
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    African Highland Initiative: A framework for research and development on NRM in the highlands of East and Central Africa
    (2000) Stroud, A
    The African Highlands Initiative (AHI) is an ecoregional programme which seeks to develop and implement an integrated research and development agenda on natural resource management (NRM) at nine selected benchmark locations in five countries in the region: Kenya, Uganda, Tanzania, Ethiopia and Madagascar. AHI research programme, while emphasizing sustainability of the highland areas will: 1) focus on integrating solutions to NRM issues by adopting participatory and integrated systems approaches; 2) strengthen partnerships and greater collaboration of a wide range of institutions and organizations to achieve more effective and efficient research and development; 3) improve the integration of biophysical and social science research, thus marrying human and technical dimensions; and 4) link policy formulation to technology development. Phase I concentrated on characterization and diagnosis of the benchmark locations to give Phase 11 (starting in 1998) more specific direction. Research in Phase I concentrated on pest—disease complexes which are exacerbated by low soil fertility in intensively cultivated systems and on soil fertility maintenance and improvement. Phase II will build on these areas and give increased attention to integrated NRM research at the community level on one hand and to regional links on the other. The premise being a greater impact by concentrating expertise and resources as well as enhancing the transfer of technology and information across the region. National agricultural research systems (NARS), International Agricultural Research Centres (IARCs), farmers, local non- governmental organizations (NGOs) and extension agents are the major partners joining forces in this effort.
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    Perspective changes everything: managing ecosystems from the inside out
    (2003) Waltner-Toews, David; Kay, James J; Neudoerffer, Cynthia; Gitau, Thomas
    In the past, environmental managers could behave as if they were managing a "natural" system to which they were external; criteria for successful management could be derived from historical data or from current pristine systems elsewhere in the world. With a few localized exceptions, this approach is no longer viable. Most of the ecosystems for which critical and urgent decisions need to be made are best seen as complex ecosocial systems, with people firmly embedded as an integral element. We can no longer manage ecosystems per se, but rather we must learn to manage our interactions within our ecological context. This view, which incorporates notions of multiple, interacting, nested hierarchies, feedback loops across space and time, and radical uncertainty with regard to prediction of system behavior, requires rethinking. How should we now think about science and science-based management? Post-normal science, complex systems theories, and the creation of collective narratives offer the best hope for making progress in this field. We use several ecosystem management and community health programs in Peru, Kenya, and Nepal to demonstrate the characteristics necessary for this kind of "inside-out" approach.