8 research outputs found

    Comparing four service delivery models for adolescent girls and young women through the Girl Power' study: Protocol for a multisite quasi-experimental cohort study

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    In sub-Saharan Africa, adolescent girls and young women (AGYW) face a range of sexual and reproductive health (SRH) challenges. Clinical, behavioural and structural interventions have each reduced these risks and improved health outcomes. However, combinations of these interventions have not been compared with each other or with no intervention at all. The Girl Power' study is designed to systematically make these comparisons. Methods and analysis Four comparable health facilities in Malawi and South Africa (n=8) were selected and assigned to one of the following models of care: (1) Standard of care: AGYW can receive family planning, HIV testing and counselling (HTC), and sexually transmitted infection (STI) syndromic management in three separate locations with three separate queues with the general population. No youth-friendly spaces, clinical modifications or trainings are offered, (2) Youth-Friendly Health Services (YFHS): AGYW are meant to receive integrated family planning, HTC and STI services in dedicated youth spaces with youth-friendly modifications and providers trained in YFHS, (3) YFHS+behavioural intervention (BI): In addition to YFHS, AGYW can attend 12 monthly theory-driven, facilitator-led, interactive sessions on health, finance and relationships, (4) YFHS+BI+conditional cash transfer (CCT): in addition to YFHS and BI, AGYW receive up to 12 CCTs conditional on monthly BI session attendance. At each clinic, 250 AGYW 15-24 years old (n=2000 total) will be consented, enrolled and followed for 1 year. Each participant will complete a behavioural survey at enrolment, 6 months and 12 months. All clinical, behavioural and CCT services will be captured. Outcomes of interest include uptake of each package element and reduction in HIV risk behaviours. A qualitative substudy will be conducted. Ethics/dissemination This study has received ethical approval from the University of North Carolina Institutional Review Board, the University of Cape Town Human Research Ethics Committee and Malawi's National Health Sciences Research Committee. Study plans, processes and findings will be disseminated to stakeholders, in peer-reviewed journals and at conferences

    Comparing youth-friendly health services to the standard of care through "girl Power-Malawi": A quasi-experimental cohort study

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    Background: Adolescent girls and young women (AGYW) face challenges to seeking HIV and sexual and reproductive health services in sub-Saharan Africa. Integrated approaches designed for AGYW may facilitate service uptake, but rigorous evaluation is needed. Methods: Four comparable public-sector health centers were selected in Malawi and randomly assigned to a service delivery model. One offered "standard of care" (SOC), consisting of vertical HIV testing, family planning, and sexually transmitted infection management in adult-oriented spaces, by providers without extra training. Three offered youth-friendly health services (YFHS), consisting of the same SOC services in integrated youth-dedicated spaces and staffed by youth-friendly peers and providers. In each health center, AGYW aged 15-24 years were enrolled and followed over 12 months to determine use of HIV testing, condoms, and hormonal contraception. The SOC and YFHS models were compared using adjusted risk differences and incidence rate ratios. Findings: In 2016, 1000 AGYW enrolled (N = 250/health center). Median age was 19 years (interquartile range = 17-21 years). Compared with AGYW in the SOC, those in the YFHS models were 23% [confidence interval (CI): 16% to 29%)] more likely to receive HIV testing, 57% (CI: 51% to 63%) more likely to receive condoms, and 39% (CI: 34% to 45%) more likely to receive hormonal contraception. Compared with AGYW in the SOC, AGYW in the YFHS models accessed HIV testing 2.4 (CI: 1.9 to 2.9) times more, condoms 7.9 (CI: 6.0 to 10.5) times more, and hormonal contraception 6.0 (CI: 4.2 to 8.7) times more. Conclusions: A YFHS model led to higher health service use. Implementation science is needed to guide scale-up

    The distribution of covert microbial natural enemies of a globally invasive crop pest, fall armyworm, in Africa: enemy-release and spillover events

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    1. Invasive species pose a significant threat to biodiversity and agriculture worldwide. Natural enemies play an important part in controlling pest populations, yet we understand very little about the presence and prevalence of natural enemies during the early invasion stages. 2. Microbial natural enemies of fall armyworm (Spodoptera frugiperda) are known in its native region, however, they have not yet been identified in Africa where fall armyworm has been an invasive crop pest since 2016. Larval samples were screened from Malawi, Rwanda, Kenya, Zambia, Sudan, and Ghana for the presence of four different microbial natural enemies; two nucleopolyhedroviruses, Spodoptera frugiperda NPV (SfMNPV) and Spodoptera exempta NPV (SpexNPV); the fungal pathogen Metarhizium rileyi; and the bacterium Wolbachia. This study aimed to identify which microbial pathogens are present in invasive fall armyworm, and determine the geographical, meteorological, and temporal variables that influence prevalence. 3. Within three years of arrival, fall armyworm was exposed to all four microbial natural enemies. SfMNPV probably arrived with fall armyworm from the Americas, but this is the first putative evidence of host spillover from Spodoptera exempta (African armyworm) to fall armyworm for the endemic pathogen SpexNPV and for Wolbachia. It is also the first confirmed incidence of M. rileyi infecting fall armyworm in Africa. 4. Natural enemies were localised, with variation being observed both nationally and temporally. The prevalence of SfMNPV (the most common natural enemy) was predominantly explained by variables associated with the weather; declining with increasing rainfall and increasing with temperature. However, virus prevalence also increased as the growing season progressed. 5. The infection of an invasive species with a natural enemy from its native range and novel pathogens specific to its new range has important consequences for understanding the population ecology of invasive species and insect-pathogen interactions. Additionally, whilst it is widely known that temporal and geographic factors affect insect populations, this study reveals that these are important in understanding the distribution of microbial natural enemies associated with invasive pests during the early stages of invasion, and provide baseline data for future studies

    Identification of the Ubiquitous Antioxidant Tripeptide Glutathione as a Fruit Fly Semiochemical

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    Many insects mark their oviposition sites with a host marking pheromone (HMP) to deter other females from overexploiting these sites. Previous studies have identified and used HMPs to manage certain fruit fly species; however, few are known for African indigenous fruit flies. The HMP of the African fruit fly, Ceratitis cosyra, was identified as the ubiquitous plant and animal antioxidant tripeptide, glutathione (GSH). GSH was isolated from the aqueous extract of adult female fecal matter and characterized by LC-QTOF-MS. GSH level increased with increasing age of female fecal matter, with highest concentration detected from 2-week-old adult females. Additionally, GSH levels were 5−10-times higher in fecal matter than in the ovipositor or hemolymph extracts of females. In bioassays, synthetic GSH reduced oviposition responses in conspecifics of C. cosyra and the heterospecific species C. rosa, C. fasciventris, C. capitata, and Zeugodacus cucurbitae. These results represent the first report of a ubiquitous antioxidant as a semiochemical in insects and its potential use in fruit fly management

    Global genomic signature reveals the evolution of fall armyworm in the Eastern hemisphere

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    The major plant pest fall armyworm (FAW), Spodoptera frugiperda, is native to the Americas and has colonized Africa and Asia within the Eastern hemisphere since 2016, causing severe damage to multiple agricultural crop species. However, the genetic origin of these invasive populations requires more in‐depth exploration. We analysed genetic variation across the genomes of 280 FAW individuals from both the Eastern hemisphere and the Americas. The global range‐wide genetic structure of FAW shows that the FAW in America has experienced deep differentiation, largely consistent with the Z‐chromosomal Tpi haplotypes commonly used to differentiate ‘corn‐strain’ and ‘rice‐strain’ populations. The invasive populations from Africa and Asia are different from the American ones and have a relatively homogeneous population structure, consistent with the common origin and recent spreading from Africa to Asia. Our analyses suggest that north‐ and central American ‘corn‐strain’ FAW are the most likely sources of the invasion into the Eastern hemisphere. Furthermore, evidence based on genomic, transcriptomic and mitochondrial haplotype network analyses indicates an earlier, independent introduction of FAW into Africa, with subsequent migration into the recent invasive population

    The effectiveness of consistent roguing in managing banana bunchy top disease in smallholder production in Africa

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    The removal of infected individuals is a common practice in the management of plant disease outbreaks. It minimizes the contact between healthy individuals and inoculum sources by reducing the infectious window of contaminated individuals. This requires early detection and consistent removal at landscape scale. Roguing of mats with symptoms of banana bunchy top disease (BBTD) in Cavendish banana production systems has been tested in Australia, using trained personnel, but has never been tested in smallholder systems. We studied the effectiveness of long-term consistent roguing in prolonging the productivity of banana orchards under smallholder farming systems in highland banana and plantain dominated production systems in Africa. We assessed the possibility of low-risk seed sourcing from the managed plots. Roguing reduced BBTD incidence to 2% in managed farmer fields and to 10% in experimental field plots, while a nonmanaged field eventually collapsed in the same period. With roguing, new infections decreased monthly compared to an exponential increase in a non managed field. The emergence of new infections in both managed and non managed farms followed a seasonal cycle. BBTD managed plots were a source of low-risk seed for replacing the rogued mats in the same fields, but perhaps not safe for use in nonendemic areas. We conclude that it is possible for smallholder farmers to recover and maintain banana productivity with rigorous roguing, which would entail early identification of symptoms and early removal of diseased mats. Studies are needed on the intensity of roguing under different disease and production conditions

    The distribution of covert microbial natural enemies of a globally invasive crop pest, fall armyworm, in Africa: enemy-release and spillover events.

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    Invasive species pose a significant threat to biodiversity and agriculture world-wide. Natural enemies play an important part in controlling pest populations, yet we understand very little about the presence and prevalence of natural enemies during the early invasion stages. Microbial natural enemies of fall armyworm Spodoptera frugiperda are known in its native region, however, they have not yet been identified in Africa where fall armyworm has been an invasive crop pest since 2016. Larval samples were screened from Malawi, Rwanda, Kenya, Zambia, Sudan and Ghana for the presence of four different microbial natural enemies; two nucleopolyhedroviruses, Spodoptera frugiperda NPV (SfMNPV) and Spodoptera exempta NPV (SpexNPV); the fungal pathogen Metarhizium rileyi; and the bacterium Wolbachia. This study aimed to identify which microbial pathogens are present in invasive fall armyworm, and determine the geographical, meteorological and temporal variables that influence prevalence. Within 3 years of arrival, fall armyworm was exposed to all four microbial natural enemies. SfMNPV probably arrived with fall armyworm from the Americas, but this is the first putative evidence of host spillover from Spodoptera exempta (African armyworm) to fall armyworm for the endemic pathogen SpexNPV and for Wolbachia. It is also the first confirmed incidence of M. rileyi infecting fall armyworm in Africa. Natural enemies were localised, with variation being observed both nationally and temporally. The prevalence of SfMNPV (the most common natural enemy) was predominantly explained by variables associated with the weather; declining with increasing rainfall and increasing with temperature. However, virus prevalence also increased as the growing season progressed. The infection of an invasive species with a natural enemy from its native range and novel pathogens specific to its new range has important consequences for understanding the population ecology of invasive species and insect–pathogen interactions. Additionally, while it is widely known that temporal and geographic factors affect insect populations, this study reveals that these are important in understanding the distribution of microbial natural enemies associated with invasive pests during the early stages of invasion, and provide baseline data for future studies
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