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BACKGROUND: Shortage of skilled workforce is a global concern but represents a critical bottleneck to Africa's development. While global academic partnerships have the potential to help tackle this development bottleneck, they are criticised for inadequate attention to equity, impact, and sustainability. We propose a new values-driven partnership model for sustainable and equitable global partnerships that achieve impact. METHOD: The model was based on the authors' experiences of participation in over 30 partnerships and used insights from the Capability Approach. RESULTS: We developed an Academic Partnership Maturity Model, with five levels of maturity, extending from pre-contemplative to mature partnerships. The level of maturity increases depending on the level of freedom, equity, diversity, and agency afforded to the partners. The approach offers a framework for establishing a forward-looking partnership anchored in mutual learning, empowerment, and autonomy. CONCLUSION: This is a pragmatic model limited by the biases of experiential knowledge. Further development of the concept, including metrics and an evaluation tool kit are needed to assist partners and funders.
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Organizaciones , HumanosRESUMEN
BACKGROUND: The suitability of using clinical assessment to identify patients with podoconiosis in endemic communities has previously been demonstrated. In this study, we explored the feasibility and accuracy of using Community Health Implementers (CHIs) for the large scale clinical screening of the population for podoconiosis in North-west Cameroon. METHODS: Before a regional podoconiosis mapping, 193 CHIs and 50 health personnel selected from 6 health districts were trained in the clinical diagnosis of the disease. After training, CHIs undertook community screening for podoconiosis patients under health personnel supervision. Identified cases were later re-examined by a research team with experience in the clinical identification of podoconiosis. RESULTS: Cases were identified by CHIs with an overall positive predictive value (PPV) of 48.5% [34.1-70%]. They were more accurate in detecting advanced stages of the disease compared to early stages; OR 2.07, 95% CI = 1.15-3.73, p = 0.015 for all advanced stages). Accuracy of detecting cases showed statistically significant differences among health districts (χ2 = 25.30, p = 0.0001). CONCLUSION: Podoconiosis being a stigmatized disease, the use of CHIs who are familiar to the community appears appropriate for identifying cases through clinical diagnosis. However, to improve their effectiveness and accuracy, more training, supervision and support are required. More emphasis must be given in identifying early clinical stages and in health districts with relatively lower PPVs.
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Agentes Comunitarios de Salud , Elefantiasis/diagnóstico , Accesibilidad a los Servicios de Salud , Área sin Atención Médica , Investigadores , Adulto , Camerún/epidemiología , Elefantiasis/epidemiología , Elefantiasis/patología , Elefantiasis/prevención & control , Estudios de Factibilidad , Femenino , Humanos , Masculino , Tamizaje Masivo/métodos , Población Rural , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Podoconiosis is a tropical lymphedema resulting from long-term barefoot exposure to red-clay soil derived from volcanic rock. The World Health Organization recently designated it as a neglected tropical disease. Podoconiosis develops in only a subgroup of exposed people, and studies have shown familial clustering with high heritability (63%). METHODS: We conducted a genomewide association study of 194 case patients and 203 controls from southern Ethiopia. Findings were validated by means of family-based association testing in 202 family trios and HLA typing in 94 case patients and 94 controls. RESULTS: We found a genomewide significant association of podoconiosis with the single-nucleotide polymorphism (SNP) rs17612858, located 5.8 kb from the HLA-DQA1 locus (in the allelic model: odds ratio, 2.44; 95% confidence interval [CI], 1.82 to 3.26; P=1.42×10(-9); and in the additive model: odds ratio, 2.19; 95% CI, 1.66 to 2.90; P=3.44×10(-8)), and suggestive associations (P<1.0×10(-5)) with seven other SNPs in or near HLA-DQB1, HLA-DQA1, and HLA-DRB1. We confirmed these associations using family-based association testing. HLA typing showed the alleles HLA-DRB1*0701 (odds ratio, 2.00), DQA1*0201 (odds ratio, 1.91), and DQB1*0202 (odds ratio, 1.79) and the HLA-DRB1*0701-DQB1*0202 haplotype (odds ratio, 1.92) were risk variants for podoconiosis. CONCLUSIONS: Association between variants in HLA class II loci with podoconiosis (a noncommunicable disease) suggests that the condition may be a T-cell-mediated inflammatory disease and is a model for gene-environment interactions that may be relevant to other complex genetic disorders. (Funded by the Wellcome Trust and others.).
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Elefantiasis/genética , Enfermedades Endémicas , Genes MHC Clase II , Predisposición Genética a la Enfermedad , Cadenas alfa de HLA-DQ/genética , Adulto , Alelos , Estudios de Casos y Controles , Elefantiasis/epidemiología , Etiopía , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido SimpleRESUMEN
Africa is home to genetically diverse human populations. We compared the genetic structure of the Wolaita ethnic population from Southern Ethiopia (WETH, n=120) with HapMap populations using genome-wide variants. We investigated allele frequencies of 443 clinically and pharmacogenomically relevant genetic variants in WETH compared with HapMap populations. We found that WETH were genetically most similar to the Kenya Maasai and least similar to the Japanese in HapMap. Variant alleles associated with increased risk of adverse reactions to drugs used for treating tuberculosis (rs1799929 and rs1495741 in NAT2), thromboembolism (rs7294, rs9923231 and rs9934438 in VKORC1), and HIV/AIDS and solid tumors (rs2242046 in SLC28A1) had significantly higher frequencies in WETH compared with African ancestry HapMap populations. Our results illustrate that clinically relevant pharmacogenomic loci display allele frequency differences among African populations. We conclude that drug dosage guidelines for important global health diseases should be validated in genetically diverse African populations.
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Población Negra/etnología , Población Negra/genética , Variación Genética/genética , Farmacogenética/métodos , Vigilancia de la Población , Estudios de Cohortes , Etiopía/etnología , Humanos , Polimorfismo de Nucleótido Simple/genética , Vigilancia de la Población/métodosRESUMEN
INTRODUCTION: The precise trigger of podoconiosis - endemic non-filarial elephantiasis of the lower legs - is unknown. Epidemiological and ecological studies have linked the disease with barefoot exposure to red clay soils of volcanic origin. Histopathology investigations have demonstrated that silicon, aluminium, magnesium and iron are present in the lower limb lymph node macrophages of both patients and non-patients living barefoot on these clays. We studied the spatial variation (variations across an area) in podoconiosis prevalence and the associated environmental factors with a goal to better understanding the pathogenesis of podoconiosis. METHODS: Fieldwork was conducted from June 2011 to February 2013 in 12 kebeles (administrative units) in northern Ethiopia. Geo-located prevalence data and soil samples were collected and analysed along with secondary geological, topographic, meteorological and elevation data. Soil data were analysed for chemical composition, mineralogy and particle size, and were interpolated to provide spatially continuous information. Exploratory, spatial, univariate and multivariate regression analyses of podoconiosis prevalence were conducted in relation to primary (soil) and secondary (elevation, precipitation, and geology) covariates. RESULTS: Podoconiosis distribution showed spatial correlation with variation in elevation and precipitation. Exploratory analysis identified that phyllosilicate minerals, particularly clay (smectite and kaolinite) and mica groups, quartz (crystalline silica), iron oxide, and zirconium were associated with podoconiosis prevalence. The final multivariate model showed that the quantities of smectite (RR = 2.76, 95% CI: 1.35, 5.73; p = 0.007), quartz (RR = 1.16, 95% CI: 1.06, 1.26; p = 0.001) and mica (RR = 1.09, 95% CI: 1.05, 1.13; p < 0.001) in the soil had positive associations with podoconiosis prevalence. CONCLUSIONS: More quantities of smectite, mica and quartz within the soil were associated with podoconiosis prevalence. Together with previous work indicating that these minerals may influence water absorption, potentiate infection and be toxic to human cells, the present findings suggest that these particles may play a role in the pathogenesis of podoconiosis and acute adenolymphangitis, a common cause of morbidity in podoconiosis patients.
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Elefantiasis/epidemiología , Monitoreo del Ambiente/métodos , Mapeo Geográfico , Contaminantes del Suelo/análisis , Elefantiasis/diagnóstico , Etiopía/epidemiología , Humanos , Factores de RiesgoRESUMEN
BACKGROUND: Understanding local contextual factors is important when conducting international collaborative studies in low-income country settings. Rapid ethical assessment (a brief qualitative intervention designed to map the ethical terrain of a research setting prior to recruitment of participants), has been used in a range of research-naïve settings. We used rapid ethical assessment to explore ethical issues and challenges associated with approaching communities and gaining informed consent in North West Cameroon. METHODS: This qualitative study was carried out in two health districts in the North West Region of Cameroon between February and April 2012. Eleven focus group discussions (with a total of 107 participants) were carried out among adult community members, while 72 in-depth interviews included health workers, non-government organisation staff and local community leaders. Data were collected in English and pidgin, translated where necessary into English, transcribed and coded following themes. RESULTS: Many community members had some understanding of informed consent, probably through exposure to agricultural research in the past. Participants described a centralised permission-giving structure in their communities, though there was evidence of some subversion of these structures by the educated young and by women. Several acceptable routes for approaching the communities were outlined, all including the health centre and the Fon (traditional leader). The importance of time spent in sensitizing the community and explaining information was stressed. CONCLUSIONS: Respondents held relatively sophisticated understanding of consent and were able to outline the structures of permission-giving in the community. Although the structures are unique to these communities, the role of certain trusted groups is common to several other communities in Kenya and Ethiopia explored using similar techniques. The information gained through Rapid Ethical Assessment will form an important guide for future studies in North West Cameroon.
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Conocimientos, Actitudes y Práctica en Salud , Consentimiento Informado/ética , Características de la Residencia , Adolescente , Adulto , Anciano , Camerún , Comprensión , Femenino , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad , Pobreza , Investigación Cualitativa , Adulto JovenRESUMEN
BACKGROUND: Rapid Ethical Assessment (REA) is a form of rapid ethnographic assessment conducted at the beginning of research project to guide the consent process with the objective of reconciling universal ethical guidance with specific research contexts. The current study is conducted to assess the perceived relevance of introducing REA as a mainstream tool in Ethiopia. METHODS: Mixed methods research using a sequential explanatory approach was conducted from July to September 2012, including 241 cross-sectional, self-administered and 19 qualitative, in-depth interviews among health researchers and regulators including ethics committee members in Ethiopian health research institutions and universities. RESULTS: In their evaluation of the consent process, only 40.2% thought that the consent process and information given were adequately understood by study participants; 84.6% claimed they were not satisfied with the current consent process and 85.5% thought the best interests of study participants were not adequately considered. Commonly mentioned consent-related problems included lack of clarity (48.1%), inadequate information (34%), language barriers (28.2%), cultural differences (27.4%), undue expectations (26.6%) and power imbalances (20.7%). About 95.4% believed that consent should be contextualized to the study setting and 39.4% thought REA would be an appropriate approach to improve the perceived problems. Qualitative findings helped to further explore the gaps identified in the quantitative findings and to map-out concerns related to the current research consent process in Ethiopia. Suggestions included, conducting REA during the pre-test (pilot) phase of studies when applicable. The need for clear guidance for researchers on issues such as when and how to apply the REA tools was stressed. CONCLUSION: The study findings clearly indicated that there are perceived to be correctable gaps in the consent process of medical research in Ethiopia. REA is considered relevant by researchers and stakeholders to address these gaps. Exploring further the feasibility and applicability of REA is recommended.
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Investigación sobre Servicios de Salud/ética , Consentimiento Informado , Investigadores/ética , Adulto , Estudios Transversales , Comités de Ética , Etiopía , Conocimientos, Actitudes y Práctica en Salud , Humanos , Consentimiento Informado/ética , Masculino , Persona de Mediana Edad , Prohibitinas , Investigación Cualitativa , Sujetos de Investigación , Encuestas y CuestionariosRESUMEN
Available evidences suggest that podoconiosis is triggered by long term exposure of bare feet to volcanic red clay soil particles. Previous genome-wide studies in Ethiopia showed association between the HLA class II region and disease susceptibility. However, functional relationships between the soil trigger, immunogenetic risk factors and the immunological basis of the disease are uncharted. Therefore, we aimed to characterise the immune profile and gene expression of podoconiosis patients relative to endemic healthy controls. Peripheral blood immunophenotyping of T cells indicated podoconiosis patients had significantly higher CD4 and CD8 T cell surface HLA-DR expression compared to healthy controls while CD62L expression was significantly lower. The levels of the activation markers CD40 and CD86 were significantly higher on monocytes and dendritic cell subsets in patients compared to the controls. RNA sequencing gene expression data indicated higher transcript levels for activation, scavenger receptors, and apoptosis markers while levels were lower for histones, T cell receptors, variable, and constant immunoglobulin chain in podoconiosis patients compared to healthy controls. Our finding provides evidence that podoconiosis is associated with high levels of immune activation and inflammation with over-expression of genes within the pro-inflammatory axis. This offers further support to a working hypothesis of podoconiosis as soil particle-driven, HLA-associated disease of immunopathogenic aetiology.
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Elefantiasis , Humanos , Elefantiasis/genética , Histonas , Antígenos CD40 , Linfocitos T CD8-positivos , ArcillaRESUMEN
BACKGROUND: The two major class A scavenger receptors are scavenger receptor A (SRA), which is constitutively expressed on most macrophage populations, and macrophage receptor with collagenous structure (MARCO), which is constitutively expressed on a more restricted subset of macrophages, (e.g. alveolar macrophages) but whose expression increases on most macrophages during the course of infection. Although the primary role of SRA appears to be clearance of modified host proteins and lipids, mice defective in expression of either MARCO or SRA are immunocompromised in multiple models of infection and in vitro assays, the scavenger receptors have been demonstrated to bind bacteria and to enhance pro-inflammatory signalling to many bacterial lung pathogens; however their importance in Mycobacterium tuberculosis infection, is less clear. METHODS: To determine whether polymorphisms in either SRA or MARCO were associated with tuberculosis, a case-control study of was performed. DNA samples from newly-detected, smear-positive, pulmonary tuberculosis cases were collected from The Gambia. Controls for this study consisted of DNA from cord bloods obtained from routine births at local Gambian health clinics. Informed written consent was obtained from patients or their parents or guardians. Ethical approval was provided by the joint The Gambian Government/MRC Joint Ethics Committee. RESULTS: We studied the frequencies of 25 polymorphisms of MSR1 (SRA) and 22 in MARCO in individuals with tuberculosis (n=1284) and matched controls (n=1349). No SNPs within the gene encoding or within 1 kb of the promoter sequence of MSR1 were associated with either susceptibility or resistance to tuberculosis. Three SNPs in MARCO (rs4491733, Mantel-Haenszel 2x2 χ2 = 6.5, p = 0.001, rs12998782, Mantel-Haenszel 2x2 χ2 = 6.59, p = 0.001, rs13389814 Mantel-Haenszel 2x2 χ2 = 6.9, p = 0.0009) were associated with susceptibility to tuberculosis and one (rs7559955, Mantel-Haenszel 2x2 χ2 = 6.9, p = 0.0009) was associated with resistance to tuberculosis. CONCLUSIONS: These findings identify MARCO as a potentially important receptor in the host response to tuberculosis.
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Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Receptores Inmunológicos/genética , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/genética , Estudios de Casos y Controles , Biología Computacional , ADN/genética , ADN/aislamiento & purificación , Femenino , Gambia/epidemiología , Frecuencia de los Genes , Heterocigoto , Humanos , Intrones , Modelos Logísticos , Macrófagos/metabolismo , Masculino , Regiones Promotoras Genéticas , Receptores Depuradores de Clase A/genética , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Understanding and accurately predicting the environmental limits, population at risk and burden of podoconiosis are critical for delivering targeted and equitable prevention and treatment services, planning control and elimination programs and implementing tailored case finding and surveillance activities. METHODS: This is secondary analysis of a nationwide podoconiosis mapping survey in Kenya. We combined national representative prevalence survey data of podoconiosis with climate and environmental data, overlayed with population figures in a geostatistical modelling framework, to predict the environmental suitability, population living in at-risk areas and number of cases of podoconiosis in Kenya. RESULTS: In 2020, the number of people living with podoconiosis in Kenya was estimated to be 9344 (95% uncertainty interval 4222 to 17 962). The distribution of podoconiosis varies by geography and three regions (Eastern, Nyanza and Western) represent >90% of the absolute number of cases. High environmental suitability for podoconiosis was predicted in four regions of Kenya (Coastal, Eastern, Nyanza and Western). In total, 2.2 million people live in at-risk areas and 4.2% of the total landmass of Kenya is environmentally predisposed for podoconiosis. CONCLUSIONS: The burden of podoconiosis is relatively low in Kenya and is mostly restricted to certain small geographical areas. Our results will help guide targeted prevention and treatment approaches through local planning, spatial targeting and tailored surveillance activities.
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Elefantiasis , Humanos , Elefantiasis/epidemiología , Elefantiasis/prevención & control , Kenia/epidemiología , Prevalencia , Geografía , AmbienteRESUMEN
BACKGROUND: BCG vaccination of infants is thought to provide good protection in all settings. This study investigated whether Malawian infants made weaker responses across a cytokine panel after BCG vaccination, compared with UK infants. METHODS: Diluted whole-blood samples were cultured with Mycobacterium tuberculosis purified protein derivative for 6 days from BCG-vaccinated infants 3 months (n = 40 Malawi, 28 UK) and 12 months (n = 34 Malawi, 26 UK) after vaccination, and also from UK unvaccinated infants (n = 9 at 3 months, n = 10 at 12 months). Forty-two cytokines were measured in supernatants using a multiplex bead array assay. Principal component analysis was used to summarize the overall patterns in cytokine responses. RESULTS: We found differences in median responses in 27 of the 42 cytokines: 7 higher in the UK and 20 higher in Malawi. The cytokines with higher responses in the UK were all T helper 1 related. The cytokines with higher responses in Malawi included innate proinflammatory cytokines, regulatory cytokines, interleukin 17, T helper 2 cytokines, chemokines, and growth factors. Principal component analysis separated the BCG-vaccinated infants from Malawi from the UK vaccinated infants and from the unvaccinated infants. CONCLUSIONS: Malawian infants make cytokine responses following BCG vaccination, but the cytokine profile is different from that in the UK. The different biosignatures following BCG vaccination in the 2 settings may indicate variability in the protective efficacy of infant BCG vaccination.
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Inmunidad Adaptativa/inmunología , Vacuna BCG/inmunología , Citocinas/sangre , Tuberculosis/prevención & control , Biomarcadores/sangre , Células Cultivadas , Humanos , Lactante , Recién Nacido , Malaui , Análisis de Componente Principal , Células TH1/metabolismo , Factores de Tiempo , Tuberculina/inmunología , Tuberculosis/inmunología , Reino Unido , VacunaciónRESUMEN
The declared aim of "personalized", "stratified" or "precision" approaches is to place individual variation, as ascertained through genomic and various other biomarkers, at the heart of Scientific Medicine using it to predict risk of disease or response to therapy and to tailor interventions and target therapies so as to maximize benefit and minimize risk for individual patients and efficiency for the health care system overall. It is often contrasted to current practices for which the scientific base is rooted in concepts of a "universal biology" and a "typical" or "average patient" and in which variation is ignored. Yet both approaches equally overlook the hierarchical nature of human variation and the critical importance of differences between populations. Impact of genetic heterogeneity has to be seen within that context to be meaningful and subsequently useful. In Africa such complexity is compounded by the high effective size of its populations, their diverse histories and the diversity of the environmental terrains they occupy, rendering analysis of gene environment interactions including the establishment of phenotype genotype correlations even more cumbersome. Henceforth "Individualized" methods and approaches can only magnify the shortcomings of universal approaches if adopted without due regard to these complexities. In the current perspective we review examples of potential hurdles that may confront biomedical scientists and analysts in genomic medicine in clinical and public health genomics in Africa citing specific examples from the current SARS-COV2 pandemic and the challenges of establishing reference biobanks and pharmacogenomics reference values.
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BACKGROUND: Mycetoma is a chronic, progressively destructive disease of subcutaneous tissues and bones caused by certain species of bacteria or fungi. We conducted a cross-sectional community-based study alongside mapping of mycetoma in five administrative units with high mycetoma endemicity in the Eastern Sennar Locality, Sennar State, Sudan. METHODS: A household survey was administered which included questions about the household members, household characteristics, economic activity and history of mycetoma. A clinical examination was conducted on all members of the household. If mycetoma was suspected, an individual questionnaire was completed collecting demographic, clinical and epidemiological data as well as information on the use of health care and associated costs. Geographical coordinates and photos of the lesions were taken, and the affected persons were referred to the medical centre for confirmation of the diagnosis and treatment. We compared the characteristics of households with confirmed cases of mycetoma with those without confirmed cases, and individuals with confirmed mycetoma with those in whom mycetoma was not confirmed. RESULTS: In total 7,798 households in 60 villages were surveyed; 515 suspected cases were identified and 359 cases of mycetoma were confirmed. Approximately 15% of households with mycetoma had more than one household member affected by this disease. Households with mycetoma were worse off with respect to water supply, toilet facilities, electricity and electrical appliances compared to the survey households. Only 23% of study participants with mycetoma had sought professional help. Of these, 77% of patients travelled an average of six hours to visit a medical facility. More than half of patients had to pay towards their treatment. The estimated average cost of treatment was 26,957 Sudanese pounds per year (566 US dollars, exchange rate 2018). CONCLUSIONS: Results of this survey suggest that agricultural practices and reduced access to sanitation and clean water can be risk factors in developing mycetoma. Poor access to health care and substantial financial costs were barriers to seeking treatment for mycetoma.
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Micetoma , Humanos , Estudios Transversales , Sudán , Factores Socioeconómicos , Micetoma/terapia , Composición FamiliarRESUMEN
Background: Staphylococcus aureus is a major human pathogen and causes healthcare and community-acquired infection. Data on the extent of MRSA colonization among health-care workers (HCWs) in sub-Saharan Africa are limited. Hence, we determined the burden of MRSA colonisation among HCWs and administrative staff in Tikur Anbessa Specialised Hospital (TASH), College of Health Sciences (CHS), Addis Ababa University, Ethiopia. Methods: Using a cross-sectional study design, participants were screened for MRSA colonisation between June 2018 and August 2019 using nasal swabs. The swabs were analysed using standard laboratory methods including antibiotic resistance gene, mecA. Anonymised sociodemographic data were collected by pretested questionnaires to evaluate HCWs factors associated with MRSA carriage. Results: A total of 588 HCWs and 468 administrative staff were screened for MRSA. Women were over-represented. Overall, 49.1% (289/588) of HCWs were nurses and 25% (117/468) of the administrative staff were cleaners or laundry workers. Overall, 138 S. aureus isolates were retrieved from the nasal swabs of both groups (16.3%, 96/588 from HCWs). The burden of MRSA colonisation was 4.8% (28/580, 95% CI: 3.1-6.5%) among HCWs compared to 0.2% (1/468, 95% CI: 0.18-0.6%) of administrative staff (p value <0.05). The majority of S. aureus and all MRSA isolates were resistant to penicillin. Isolates from HCWs were more resistant to tested antibiotics than administrative staff (P-value <0.05). Conclusion: This is the first report in Ethiopia on MRSA colonization using mecA and revealed that; (i) overall carriage rates of MRSA in HCWs are comparable with observations reported in some other countries and (ii) HCWs exhibit a higher burden of MRSA carriage than administrative staff. Our data support strategic screening of MRSA and antimicrobial stewardship for better intervention measures.
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Mycobacteria naturally grow as corded biofilms in liquid media without detergent. Such detergent-free biofilm phenotypes may reflect the growth pattern of bacilli in tuberculous lung lesions. New strategies are required to treat tuberculosis, which is responsible for more deaths each year than any other bacterial disease. The lengthy 6-month regimen for drug-sensitive tuberculosis is necessary to remove antimicrobial drug tolerant populations of bacilli that persist through drug therapy. The role of biofilm-like growth in the generation of these sub-populations remains poorly understood despite the hypothesised clinical significance and mounting evidence of biofilms in pathogenesis. We adapt a three-dimensional Rotary Cell Culture System to model M. bovis BCG biofilm growth in low-shear detergent-free liquid suspension. Importantly, biofilms form without attachment to artificial surfaces and without severe nutrient starvation or environmental stress. Biofilm-derived planktonic bacilli are tolerant to isoniazid and streptomycin, but not rifampicin. This phenotypic drug tolerance is lost after passage in drug-free media. Transcriptional profiling reveals induction of cell surface regulators, sigE and BCG_0559c alongside the ESX-5 secretion apparatus in these low-shear liquid-suspension biofilms. This study engineers and characterises mycobacteria grown as a suspended biofilm, illuminating new drug discovery pathways for this deadly disease.
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Antituberculosos/farmacología , Técnicas Bacteriológicas/métodos , Biopelículas/crecimiento & desarrollo , Mycobacterium bovis/fisiología , Proteínas Bacterianas/genética , Medios de Cultivo/química , Farmacorresistencia Bacteriana , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Isoniazida/farmacología , Mycobacterium bovis/genética , Fenotipo , Rifampin/farmacología , Factor sigma/genética , Estreptomicina/farmacología , Factores de Virulencia/genéticaRESUMEN
BACKGROUND: Mycetoma is a neglected tropical disease that is reported worldwide and Sudan has the highest reported number of mycetoma infections across the globe. The incidence, prevalence and burden of mycetoma globally are not precisely known and its risk factors remain largely unelucidated. METHODS: This study aimed to identify the environmental predictors of fungal and bacterial mycetoma in Sudan and to identify areas of the country where these niche predictors are met. Demographic and clinical data from confirmed mycetoma patients seen at the Mycetoma Research Centre from 1991 to 2018 were included in this study. Regression and machine learning techniques were used to model the relationships between mycetoma occurrence in Sudan and environmental predictors. RESULTS: The strongest predictors of mycetoma occurrence were aridity, proximity to water, low soil calcium and sodium concentrations and the distribution of various species of thorny trees. The models predicted the occurrence of eumycetoma and actinomycetoma in the central and southeastern states of Sudan and along the Nile river valley and its tributaries. CONCLUSION: Our results showed that the risk of mycetoma in Sudan varies geographically and is linked to identifiable environmental risk factors. Suitability maps are intended to guide health authorities, academic institutes and organisations involved in planning national scale surveys for early case detection and management, leading to better patient treatment, prevention and control of mycetoma.
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Micetoma , Ambiente , Humanos , Micetoma/epidemiología , Enfermedades Desatendidas , Suelo , Sudán/epidemiologíaRESUMEN
BACKGROUND: Undertaking research and attaining informed consent can be challenging when there is political unrest and community mistrust. Rapid ethical appraisal (REA) is a tool that uses qualitative methods to explore sociocultural issues that may affect the ethical conduct of research. METHODS: We used REA in northeast Ethiopia shortly following a period of unrest, during which violence against researchers occurred, to assess stakeholder perceptions of research, researchers and the informed consent process. We held 32 in-depth interviews and 2 focus group discussions. RESULTS: Most community members had little awareness about podoconiosis or healthcare research. Convincing the community to donate blood for research is challenging due to association with HIV testing. The attack on researchers was mainly motivated by the community's mistrust of their intentions against the background of a volatile political situation. Social media contributed to the spread of misinformation. Lack of community engagement was also a key contributing factor. CONCLUSIONS: Using REA, we identified potential barriers to the informed consent process, participant recruitment for data and specimen collection and the smooth conduct of research. Researchers should assess existing conditions in the study area and engage with the community to increase awareness prior to commencing their research activities.
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Elefantiasis , Etiopía , Grupos Focales , Humanos , Consentimiento Informado , Prohibitinas , Investigación Cualitativa , InvestigadoresRESUMEN
Podoconiosis is a type of tropical lymphedema that is clinically distinguished from lymphatic filariasis (LF) because it is ascending and commonly bilateral but asymmetric. The disease is a result of a genetically determined inflammatory reaction to long-term exposure to mineral particles in irritant red clay soils derived mainly from volcanic soils. We conducted the first nationwide mapping of the prevalence and risk factors of podoconiosis in Kenya. We performed a population-based cross-sectional survey to determine the national prevalence of podoconiosis and included 6,228 individuals from 48 villages in 24 sub-counties across 15 counties. Participants answered a questionnaire about the history of symptoms compatible with podoconiosis, received a point-of-care antigen test, and underwent a physical examination if they had lymphedema. A confirmed case of podoconiosis was defined as a case in a resident of the study village who had lower limb bilateral and asymmetric lymphedema lasting more than 1 year, negative test results for Wuchereria bancrofti antigen, and other causes of lymphedema ruled out. Of all the individuals surveyed, 89 had lymphedema; of those, 16 of 6228 (0.3%; 95% confidence interval [CI], 0.1-0.5) were confirmed to have podoconiosis. A high prevalence of podoconiosis was found in western (Siaya, 3.1%; Busia, 0.9%) and central (Meru, 1.1%) regions, and a low prevalence was observed in northern (Marsabit, 0.2%), eastern (Makueni, 0.2%), and coastal (Tana River, 0.1%) regions. The identified risk factors were age 56 years or older (adjusted odds ratio [aOR], 5.66; 95% CI, 2.32-13.83; P < 0.001) and rarely wearing shoes (aOR, 18.92; 95% CI, 4.55-78.71; P < 0.001). These results indicated that the podoconiosis prevalence is low and localized in Kenya; therefore, elimination is achievable if appropriate disease prevention, management, and behavioral strategies are promoted.
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Elefantiasis/epidemiología , Geografía , Prevalencia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios Transversales , Monitoreo Epidemiológico , Femenino , Humanos , Kenia/epidemiología , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Podoconiosis, a debilitating lymphoedema of the leg, results from barefoot exposure to volcanic clay soil in genetically susceptible individuals. A previous genome-wide association study (GWAS) conducted in the Wolaita ethnic group from Ethiopia showed association between single nucleotide polymorphisms (SNPs) in the HLA class II region and podoconiosis. We aimed to conduct a second GWAS in a new sample (N = 1892) collected from the Wolaita and two other Ethiopian populations, the Amhara and the Oromo, also affected by podoconiosis. Fourteen SNPs in the HLA class II region showed significant genome-wide association (P < 5.0 × 10-8) with podoconiosis. The lead SNP was rs9270911 (P = 5.51 × 10-10; OR 1.53; 95% CI 1.34-1.74), located near HLA-DRB1. Inclusion of data from the first GWAS (combined N = 2289) identified 47 SNPs in the class II HLA region that were significantly associated with podoconiosis (lead SNP also rs9270911 (P = 2.25 × 10-12). No new loci outside of the HLA class II region were identified in this more highly-powered second GWAS. Our findings confirm the HLA class II association with podoconiosis suggesting HLA-mediated abnormal induction and regulation of immune responses may have a direct role in its pathogenesis.
Asunto(s)
Elefantiasis , Etnicidad/genética , Predisposición Genética a la Enfermedad/etnología , Cadenas HLA-DRB1/genética , Polimorfismo de Nucleótido Simple , Elefantiasis/etnología , Elefantiasis/genética , Etiopía/etnología , Femenino , Estudio de Asociación del Genoma Completo , Humanos , MasculinoRESUMEN
BACKGROUND: Podoconiosis is one of the leading causes of lymphoedema-related morbidity in low-income settings, but little is known about the scale of its health and economic impact. This information is required to inform control programme planning and policy. In this study, we estimated the health and economic burden of podoconiosis in Ethiopia. METHODS: We developed a model to estimate the health burden attributed to podoconiosis in terms of the number of disability-adjusted life years (DALYs) and the economic burden. We estimated the economic burden by quantifying the treatment and morbidity-management costs incurred by the healthcare system in managing clinical cases, patients' out-of-pocket costs and their productivity costs. RESULTS: In 2017, there were 1.5 million cases of podoconiosis in Ethiopia, which corresponds to 172 073 DALYs or 182 per 100 000 people. The total economic burden of podoconiosis in Ethiopia is estimated to be US$213.2 million annually and 91.1% of this resulted from productivity costs. The average economic burden per podoconiosis case was US$136.9. CONCLUSIONS: The national cost of podoconiosis is formidable. If control measures are scaled up and the morbidity burden reduced, this will lead to Ethiopia saving millions of dollars. Our estimates provide important benchmark economic costs to programme planners, policymakers and donors for resource allocation and priority setting.