128 research outputs found

    Molecular Markers for Genetic Diversity Studies in African Leafy Vegetables

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    African leafy vegetables are becoming important crops in tackling nutrition and food security in many parts of sub-Saharan Africa, since they provide important micronutrients and vitamins, and help resource-poor farm families bridge lean periods of food shortage. Genetic diversity studies are essential for crop improvement programmes as well as germplasm conservation efforts, and research on genetic diversity of these vegetables using molecular markers has been increasing over time. Diversity studies have evolved from the use of morphological and biochemical markers to molecular markers. Molecular markers provide valuable data, since they detect mostly selectively neutral variations at the DNA level. They are well established and their strengths and limitations have been described. New marker types are being developed from a combination of the strengths of the basic techniques to improve sensitivity, reproducibility, polymorphic information content, speed and cost. This review discusses the principles of some of the established molecular markers and their application to genetic diversity studies of African leafy vegetables with a main focus on the most common Solanum, Amaranthus, Cleome and Vigna species.BMBF/HORTINLEABM

    Intimate partner violence as seen in post-conflict eastern Uganda: prevalence, risk factors and mental health consequences.

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    BACKGROUND: Conflict and post-conflict communities in sub-Saharan Africa have a high under recognised problem of intimate partner violence (IPV). Part of the reason for this has been the limited data on IPV from conflict affected sub-Saharan Africa. This paper reports on the prevalence, risk factors and mental health consequences of IPV victimisation in both gender as seen in post-conflict eastern Uganda. METHODS: A cross-sectional survey was carried out in two districts of eastern Uganda. The primary outcome of IPV victimisation was assessed using a modified Intimate Partner Violence assessment questionnaire of the American Congress of Obstetricians and Gynaecologists. RESULTS: The prevalence of any form of IPV victimisation (physical and/or sexual and/or psychological IPV) in this study was 43.7 % [95 % CI, 40.1-47.4 %], with no statistically significant difference between the two gender. The factors significantly associated with IPV victimisation were: sub-county (representing ecological factors), poverty, use of alcohol, and physical and sexual war torture experiences. The mental health problems associated with IPV victimisation were probable problem alcohol drinking, attempted suicide and probable major depressive disorder. CONCLUSION: In post-conflict eastern Uganda, in both gender, war torture was a risk factor for IPV victimisation and IPV victimisation was associated with mental health problems

    Do topical repellents divert mosquitoes within a community? Health equity implications of topical repellents as a mosquito bite prevention tool.

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    OBJECTIVES: Repellents do not kill mosquitoes--they simply reduce human-vector contact. Thus it is possible that individuals who do not use repellents but dwell close to repellent users experience more bites than otherwise. The objective of this study was to measure if diversion occurs from households that use repellents to those that do not use repellents. METHODS: The study was performed in three Tanzanian villages using 15%-DEET and placebo lotions. All households were given LLINs. Three coverage scenarios were investigated: complete coverage (all households were given 15%-DEET), incomplete coverage (80% of households were given 15%-DEET and 20% placebo) and no coverage (all households were given placebo). A crossover study design was used and coverage scenarios were rotated weekly over a period of ten weeks. The placebo lotion was randomly allocated to households in the incomplete coverage scenario. The level of compliance was reported to be close to 100%. Mosquito densities were measured through aspiration of resting mosquitoes. Data were analysed using negative binomial regression models. FINDINGS: Repellent-users had consistently fewer mosquitoes in their dwellings. In villages where everybody had been given 15%-DEET, resting mosquito densities were fewer than half that of households in the no coverage scenario (Incidence Rate Ratio [IRR]=0.39 (95% confidence interval [CI]: 0.25-0.60); p<0.001). Placebo-users living in a village where 80% of the households used 15%-DEET were likely to have over four-times more mosquitoes (IRR=4.17; 95% CI: 3.08-5.65; p<0.001) resting in their dwellings in comparison to households in a village where nobody uses repellent. CONCLUSIONS: There is evidence that high coverage of repellent use could significantly reduce man-vector contact but with incomplete coverage evidence suggests that mosquitoes are diverted from households that use repellent to those that do not. Therefore, if repellents are to be considered for vector control, strategies to maximise coverage are required

    Use of a Semi-field System to Evaluate the Efficacy of Topical Repellents under user Conditions Provides a Disease Exposure free Technique Comparable with Field Data.

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    Before topical repellents can be employed as interventions against arthropod bites, their efficacy must be established. Currently, laboratory or field tests, using human volunteers, are the main methods used for assessing the efficacy of topical repellents. However, laboratory tests are not representative of real life conditions under which repellents are used and field-testing potentially exposes human volunteers to disease. There is, therefore, a need to develop methods to test efficacy of repellents under real life conditions while minimizing volunteer exposure to disease. A lotion-based, 15% N, N-Diethyl-3-methylbenzamide (DEET) repellent and 15% DEET in ethanol were compared to a placebo lotion in a 200 sq m (10 m x 20 m) semi-field system (SFS) against laboratory-reared Anopheles arabiensis mosquitoes and in full field settings against wild malaria vectors and nuisance-biting mosquitoes. The average percentage protection against biting mosquitoes over four hours in the SFS and field setting was determined. A Poisson regression model was then used to determine relative risk of being bitten when wearing either of these repellents compared to the placebo. Average percentage protection of the lotion-based 15% DEET repellent after four hours of mosquito collection was 82.13% (95% CI 75.94-88.82) in the semi-field experiments and 85.10% (95% CI 78.97-91.70) in the field experiments. Average percentage protection of 15% DEET in ethanol after four hours was 71.29% (CI 61.77-82.28) in the semi-field system and 88.24% (84.45-92.20) in the field. Semi-field evaluation results were comparable to full-field evaluations, indicating that such systems could be satisfactorily used in measuring efficacy of topically applied mosquito repellents, thereby avoiding risks of exposure to mosquito-borne pathogens, associated with field testing

    Provider Attitudes toward the Voluntary Medical Male Circumcision Scale-Up in Kenya, South Africa, Tanzania and Zimbabwe.

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    Countries participating in voluntary medical male circumcision (VMMC) scale-up have adopted most of six elements of surgical efficiency, depending on national policy. However, effective implementation of these elements largely depends on providers' attitudes and subsequent compliance. We explored the concordance between recommended practices and providers' perceptions toward the VMMC efficiency elements, in part to inform review of national policies. As part of Systematic Monitoring of the VMMC Scale-up (SYMMACS), we conducted a survey of VMMC providers in Kenya, South Africa, Tanzania, and Zimbabwe. SYMMACS assessed providers' attitudes and perceptions toward these elements in 2011 and 2012. A restricted analysis using 2012 data to calculate unadjusted odds ratios and 95% confidence intervals for the country effect on each attitudinal outcome was done using logistic regression. As only two countries allow more than one cadre to perform the surgical procedure, odds ratios looking at country effect were adjusted for cadre effect for these two countries. Qualitative data from open-ended responses were used to triangulate with quantitative analyses. This analysis showed concordance between each country's policies and provider attitudes toward the efficiency elements. One exception was task-shifting, which is not authorized in South Africa or Zimbabwe; providers across all countries approved this practice. The decision to adopt efficiency elements is often based on national policies. The concordance between the policies of each country and provider attitudes bodes well for compliance and effective implementation. However, study findings suggest that there may be need to consult providers when developing national policies.\u

    Effect of mother’s migration on under-two mortality in Kenya

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    This study examines the effect of mothers’ migration status controlling for other proximate factors (socio-economic, environmental and bio-demographic characteristics) on under two mortality in Kenya. Data used were drawn from 2003 Kenya Demographic Health Survey with focus on infants and children below two years in age. A total of 5949 infants and children born five years before the survey are used in the analysis. Cox proportional hazard model is used to assess the relative effect of the migration status (migrant or non-migrant) of the mother on survival rates controlling for other explanatory variables. The general results shows that children of migrant mothers especially those of urban-rural migrants face a higher mortality risk compared to those of non-migrant mothers. The results show that failure to account for migration may alter the estimation of urban-rural differentials in childhood mortality

    Community opinion leaders in Ghana speak out on adolescent sexuality: What are the issues?

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    This policy brief reports on a study that is a component of a larger study that assessed the sexual and reproductive health (SRH) needs of adolescents in four slums in two regions of Ghana. The study’s focus on this perspective stems from the fact that there is a lack of evidence surrounding the outlook of community opinion leaders on adolescent reproductive health in this setting. Understanding what adults think about major adolescent SRH issues in their communities (including the SRH rights of adolescents, adult–adolescent communication about SRH issues, and service-seeking and sexual behavior outcomes) provides insight into how adults perceive and influence the lives of young people, and therefore, how programs could be designed to better serve the sexual health needs of adolescents. The brief summarizes key findings that identify the issues facing these community opinion leaders

    Evaluation of personal protection afforded by repellent-treated sandals against mosquito bites in south-eastern Tanzania

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    Outdoor and early evening mosquito biting needs to be addressed if malaria elimination is to be achieved. While indoor-targeted interventions, such as insecticide-treated nets and indoor residual spraying, remain essential, complementary approaches that tackle persisting outdoor transmission are urgently required to maximize the impact. Major malaria vectors principally bite human hosts around the feet and ankles. Consequently, this study investigated whether sandals treated with efficacious spatial repellents can protect against outdoor biting mosquitoes. Sandals affixed with hessian bands measuring 48 cm treated with 0.06 g, 0.10 g and 0.15 g of transfluthrin were tested in large cage semi-field and full field experiments. Sandals affixed with hessian bands measuring 240 cm and treated with 0.10 g and 0.15 g of transfluthrin were also tested semi field experiments. Human landing catches (HLC) were used to assess reduction in biting exposure by comparing proportions of mosquitoes landing on volunteers wearing treated and untreated sandals. Sandals were tested against insectary reared Anopheles arabiensis mosquitoes in semi-field experiments and against wild mosquito species in rural Tanzania. In semi-field tests, sandals fitted with hessian bands measuring 48 cm and treated with 0.15 g, 0.10 g and 0.06 g transfluthrin reduced mosquito landings by 45.9%, (95% confidence interval (C.I.) 28-59%), 61.1% (48-71%), and 25.9% (9-40%), respectively compared to untreated sandals. Sandals fitted with hessian bands measuring 240 cm and treated with 0.15 g and 0.10 g transfluthrin reduced mosquito landings by 59% (43-71%) and 64% (48-74%), respectively. In field experiments, sandals fitted with hessian bands measuring 48 cm and treated with 0.15 g transfluthrin reduced mosquito landings by 70% (60-76%) against Anopheles gambiae sensu lato, and 66.0% (59-71%) against all mosquito species combined. Transfluthrin-treated sandals conferred significant protection against mosquito bites in semi-field and field settings. Further evaluation is recommended for this tool as a potential complementary intervention against malaria. This intervention could be particularly useful for protecting against outdoor exposure to mosquito bites. Additional studies are necessary to optimize treatment techniques and substrates, establish safety profiles and determine epidemiological impact in different settings

    Six decades of malaria vector control in southern Africa : a review of the entomological evidence-base

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    AVAILABILITY OF DATA AND MATERIALS : Information was searched and obtained from published data in the PubMed search engine. The datasets used and/or analysed during this study can be obtained from the corresponding author on reasonable request.BACKGROUND : Countries in the southern Africa region have set targets for malaria elimination between 2020 and 2030. Malaria vector control is among the key strategies being implemented to achieve this goal. This paper critically reviews published entomological research over the past six decades in three frontline malaria elimination countries namely, Botswana Eswatini and Namibia, and three second-line malaria elimination countries including Mozambique, Zambia, and Zimbabwe. The objective of the review is to assess the current knowledge and highlight gaps that need further research attention to strengthen evidence-based decision-making toward malaria elimination. METHODS : Publications were searched on the PubMed engine using search terms: “(malaria vector control OR vector control OR malaria vector*) AND (Botswana OR Swaziland OR Eswatini OR Zambia OR Zimbabwe OR Mozambique)”. Opinions, perspectives, reports, commentaries, retrospective analysis on secondary data protocols, policy briefs, and reviews were excluded. RESULTS : The search resulted in 718 publications with 145 eligible and included in this review for the six countries generated over six decades. The majority (139) were from three countries, namely Zambia (59) and Mozambique (48), and Zimbabwe (32) whilst scientific publications were relatively scanty from front-line malaria elimination countries, such as Namibia (2), Botswana (10) and Eswatini (4). Most of the research reported in the publications focused on vector bionomics generated mostly from Mozambique and Zambia, while information on insecticide resistance was mostly available from Mozambique. Extreme gaps were identified in reporting the impact of vector control interventions, both on vectors and disease outcomes. The literature is particularly scanty on important issues such as change of vector ecology over time and space, intervention costs, and uptake of control interventions as well as insecticide resistance. CONCLUSIONS : The review reveals a dearth of information about malaria vectors and their control, most noticeable among the frontline elimination countries: Namibia, Eswatini and Botswana. It is of paramount importance that malaria vector research capacity and routine entomological monitoring and evaluation are strengthened to enhance decision-making, considering changing vector bionomics and insecticide resistance, among other determinants of malaria vector control.The AFRO-II Project under the auspices of the Global Environment Facility/United Nations Environment Programme (GEF/UNEP) through the World Health Organization Regional Office for Africa (WHO-AFRO); icipe’s core donors, the Foreign, Commonwealth & Development Office (FCDO) of the UK Government; Swedish International Development Cooperation Agency (Sida); the Swiss Agency for Development and Cooperation (SDC); Federal Democratic Republic of Ethiopia; and the Kenyan Government.https://malariajournal.biomedcentral.comhj2023School of Health Systems and Public Health (SHSPH

    Are parents talking to adolescents about sexuality? Evidence from four slums in Ghana

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    This evidence brief summarizes the essential information from a part of a larger study that assessed the sexual and reproductive health (SRH) needs of adolescents in four slums in two regions of Ghana. The objective of this brief is to provide evidence to support and facilitate the improvement of parent–adolescent communication on sexuality. This study echoes several other studies by providing evidence that a majority of parents are not opposed to in-school sex education for their children and welcome the idea of empowering themselves (parents) to have productive discussions with their children. Nevertheless, there is a mismatch between the proportion of parents who believe they have discussed sexuality with their adolescents, and the number of adolescents who report they have had these discussions. Among several conclusions, the report identifies the need to better educate parents and guardians about adolescent sexual and reproductive health, as well as provide guidance on how they can effectively have these conversations
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