59 research outputs found

    MWCNTs/Ag-ZnO nanocomposite for efficient photocatalytic degradation of congo red

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    Three nanomaterials namely, zinc oxide (ZC), silver-doped zinc oxide (AZ) and multi-walled carbon nanotubes coupled with silver doped zinc oxide nanocomposite (MWAZ) were synthesized, characterized and employed for photo degradation of an organic pollutant, congo red (CR). The photocatalytic activity study showed efficient degradation of CR upon irradiation with UV and visible light in the order of MWAZ > AZ > ZC > Commercial ZnO (ZCO). Percentage photodegradation of 99% and a pseudo 1st order rate constant of 2.3 x 10-2 min-1 were achieved by MWAZ as a catalyst under visible light irradiation, implying photo- sensitizing ability of MWCNTs and the capability of MWCNTs to hinder recombination of photogenerated holes and electrons. The control experiment in the dark condition gave only 7.9% of degradation efficiency and 5.56 x 10-4 min-1 rate constant, implying the significant role of light source for catalytic degradation of CR.   Bull. Chem. Soc. Ethiop. 2020, 34(1), 55-66. DOI: https://dx.doi.org/10.4314/bcse.v34i1.

    A nonstandard Volterra difference equation for the SIS epidemiological model

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    By considering the contact rate as a function of infective individuals and by using a general distribution of the infective period, the SIS-model extends to a Volterra integral equation that exhibits complex behaviour such as the backward bifurcation phenomenon.We design a nonstandard finite difference (NSFD) scheme, which is reliable in replicating this complex dynamics. It is shown that the NSFD scheme has no spurious fixed-points compared to the equilibria of the continuous model. Furthermore, there exist two threshold parameters Rc 0 andRm0 , Rc 0 ≤ 1 ≤ Rm0 , such that the disease-free fixed-point is globally asymptotically stable (GAS) for R0, the basic reproduction number, less than Rc 0 and unstable for R0 > 1, while it is locally asymptotically stable (LAS) and coexists with a LAS endemic fixed-point forRc 0 Rm0 andRm0 < ∞. Numerical experiments that support the theory are provided.DST/NRF SARChI Chair in Mathematical Models and Methods in Bioengineering and Biosciences.http://www.thelancet.com/2016-09-30hb201

    Analysis and dynamically consistent nonstandard discretization for a rabies model in humans and dogs

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    Rabies is a fatal disease in dogs as well as in humans. A possible model to represent rabies transmission dynamics in human and dog populations is presented. The next generation matrix operator is used to determine the threshold parameter R0, that is the average number of new infective individuals produced by one infective individual intro- duced into a completely susceptible population. If R0 < 1, the disease-free equilibrium is globally asymptotically stable, while it is unstable and there exists a locally asymptot- ically stable endemic equilibrium when R0 > 1. A nonstandard nite di erence scheme that replicates the dynamics of the continuous model is proposed. Numerical tests to support the theoretical analysis are provided.DST/NRF SARChI Chair in Mathematics Models and Methods in Bioengineering and Biosciences.http://link.springer.com/journal/133982017-09-30hb2016Mathematics and Applied Mathematic

    Magnitude of Antiretroviral Drug toxicity in adult HIV patients in Ethiopia: A cohort study at seven teaching hospitals

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    Background: The introduction of antiretroviral therapy (ART) has resulted in significant mortality reduction and improvement in the quality of life. However, this has come at a cost of increased drug toxicity. The objective of this study was to assess the patterns and predictors of ART toxicity in adult HIV patients in Ethiopia.Methods: This is a prospective cohort study conducted at seven teaching hospitals between September 2009 and December 2013 involving 3921 HIV patients on ART. Adverse drug reactions (ADR) due to ART were identified based on clinical assessment and/or laboratory parameters. Multivariable random effects Poisson regression analysis was used to identify factors independently associated with toxicity.Result: ADR due to ART drugs was reported in 867 (22.1 %) of the participants; 374 (9.5%) had severe forms. About 87% of reported toxicities were limited to three organ systems – the skin, nervous system and blood. The overall incidence of ADR was 9 per 100 person years. About a third of toxicities occurred during the first six months after ART initiation with the incidence rate of 22.4 per 100 person years. Concomitant anti-tuberculosis treatment was the strongest independent predictor of toxicity.Conclusion: ADR was found to be highly prevalent in HIV patients on ART at tertiary hospitals in Ethiopia. Most of these conditions occurred early after ART initiation and in those with concomitant anti-tuberculosis treatment. Thus, routine monitoring of patients on ART should be strengthened with particular emphasis in the first 6 months. Strategies should also be devised to replace older and more toxic agents with newer and safer drugs available.Key words: HIV, ART, adverse drug reaction, incidence rate, ACM, Ethiopi

    Economic evaluation of Health Extension Program packages in Ethiopia

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    Background Ethiopia launched the Health Extension Program (HEP) in 2004, aimed at ensuring equitable community-level healthcare services through Health Extension Workers. Despite the program’s being a flagship initiative, there is limited evidence on whether investment in the program represents good value for money. This study assessed the cost and cost-effectiveness of HEP interventions to inform policy decisions for resource allocation and priority setting in Ethiopia. Methods Twenty-one health care interventions were selected under the hygiene and sanitation, family health services, and disease prevention and control sub-domains. The ingredient bottom-up and top-down costing method was employed. Cost and cost-effectiveness were assessed from the provider perspective. Health outcomes were measured using life years gained (LYG). Incremental cost per LYG in relation to the gross domestic product (GDP) per capita of Ethiopia (US852.80)wasusedtoascertainthecosteffectiveness.AllcostswerecollectedinEthiopianbirrandconvertedtoUnitedStatesdollars(US852.80) was used to ascertain the cost-effectiveness. All costs were collected in Ethiopian birr and converted to United States dollars (US) using the average exchange rate for 2018 (US1=27.67birr).Bothcostsandhealthoutcomeswerediscountedby3ResultTheaverageunitcostofprovidingselectedhygieneandsanitation,familyhealth,anddiseasepreventionandcontrolserviceswiththeHEPwasUS1 = 27.67 birr). Both costs and health outcomes were discounted by 3%. Result The average unit cost of providing selected hygiene and sanitation, family health, and disease prevention and control services with the HEP was US0.70, US4.90,andUS4.90, and US7.40, respectively. The major cost driver was drugs and supplies, accounting for 53% and 68%, respectively, of the total cost. The average annual cost of delivering all the selected interventions was US9,897.Allinterventionsfallwithin1timesGDPpercapitaperLYG,indicatingthattheyareverycosteffective(ranges:US9,897. All interventions fall within 1 times GDP per capita per LYG, indicating that they are very cost-effective (ranges: US22–295perLYG).Overall,theHEPiscosteffectivebyinvestingUS295 per LYG). Overall, the HEP is cost-effective by investing US77.40 for every LYG. Conclusion The unit cost estimates of HEP interventions are crucial for priority-setting, resource mobilization, and program planning. This study found that the program is very cost-effective in delivering community health services.publishedVersio

    Predictors of survival among adult Ethiopian patients in the national ART program at Seven University Teaching Hospitals: A prospective cohort study

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    Background: In Ethiopia, the publicly funded antiretroviral treatment (ART) program was started in 2005. Two hundred seventy-five thousand patients were enrolled in the national ART program by 2012. However, there is limited data on mortality and predictors of death among adult patients in the ART program. The study aimed to estimate mortality and risk factors for death among adult, ART-naïve patients,  started in the national ART program from January 2009 to July 2013.Methods: Multi-site, prospective, observational cohort study of adult, age &gt; 18 years, ART-naïve patients, started in the national ART program at seven university-affiliated hospitals from January 2009 - July 2013. Kaplan-Meier and Cox  regression analyses were used to estimate survival and determine risk factors for death.Results: A total of 976 patients, 594 females (60.9 %), were enrolled into the study. Median age of the cohort was 33years. The median CD4 count at start of ART was 144 cells/μl (interquartile range (IQR) 78-205), and 34.2% (330/965) had CD4 &lt; 100. Sixty-three percent (536/851) had viral load greater than 5 log copies/ml (IQR 4.7-5.7) at base line. One hundred and one deaths were recorded during  follow-up period, all-cause mortality rate 10.3%; 5.4 deaths/100 person years of observation, 95% confidence interval 4.4-6.5. Seventy percent of the deaths occurred within six months of starting ART. Cox regression analyses showed that the following measures independently predicted mortality: age &gt;51 years, (Adjusted Hazard Ratio (AHR) 4.01, P=0.003), WHO stages III&amp;IV, (AHR 1.76, p = 0.025), CD4 count, &lt;100, (AHR 2.36, p =0.006), and viral load &gt;5 log copies /ml (CHR 1.71, p = 0.037).Conclusion: There is high early on- ART mortality in patients presenting with advanced immunodeficiency. Detecting cases and initiating ART before onset of advanced immunodeficiency might improve survival.Key Words: Ethiopia, HIV clinical cohort, Antiretroviral therapy, Surviva

    Soil carbon stocks in Ethiopian forests and estimations of their future development under different forest use scenarios

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    Contributions from all land‐uses are needed if Ethiopia is to fulfil its Paris Agreement targets. The magnitude of soil carbon stock and the role of Ethiopian forest soils in climate change mitigation has not yet been clarified. In this study, soil carbon inventory in forests was carried out as a part of the Ethiopia REDD+ Programme. The performance of soil carbon models Yasso07 and CENTURY was tested by comparing the model predictions with the empirical soil organic carbon (SOC) data provided by the field inventory. In addition to that, Global Soil Organic Carbon (GSOC) map estimates by the Food and Agriculture Organization for Ethiopia were included in the comparison. The soil inventory was carried out in 2017–2018 at a subset of permanent sampling units of the National Forest Inventory conducted in 2014–2017. A combination of soil inventory data, soil carbon models and satellite images enabled to quantify the impact of forest use intensity to future SOC sinks in Ethiopian forests in a novel way. The Yasso07 and CENTURY models provided similar SOC estimates to the measured data for all biomes, and the GSOC map overestimated in biomes with larger SOC stocks. Results showed that Moist Afromontane forest biome contains twice as much SOC per unit area compared to Combretum‐Terminalia forest biome and three‐times more SOC compared to Acacia‐Commiphora. Results underlined that sustainable forest management has a high potential for soil carbon development in Ethiopian forests in near future, impacting the ability of the Country to achieve its Paris Agreement targets.202

    Establishing a multicenter longitudinal clinical cohort Study in Ethiopia: Advanced Clinical Monitoring of Antiretroviral Treatment Project

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    Background: The purpose of this paper is to describe the establishment of the  Advanced Clinical Monitoring of ART Project in Ethiopia for monitoring and  evaluation of the longitudinal effectiveness of the ART program and to show the opportunities it presents. This cohort was established in response to the 2005 call by WHO for establishing additional mechanisms for stronger monitoring of ART and the need for creating the platform to generate evidence to guide the care given for the ever increasing number of patients on ART in Ethiopia.Method: A participatory and multi-stage process which started from a consensus building workshop and steered by a mother protocol as well as guiding documents which dictated the degree of engagement and expectations was followed. The primary and secondary aims of the study were agreed upon. A multi-site longitudinal observational clinical cohort was established by a consortium of stakeholders including seven Ethiopian medical schools and their affiliated referral hospitals, John Hopkins University, Ethiopian Public Health Institute, Ministry of Science and Technology, US Centers for Disease Prevention and Control - CDC-Ethiopia, and the Federal Ministry of Health. Adult and adolescent cohorts covering the age range of 14+ years) and pediatric cohorts covering those below age 14 years were the two main cohorts. During the initial recruitment of these cohorts information was extracted from existing documents for a total of 2,100 adult participants. In parallel, a prospective cohort of 1,400 adult and adolescent patients were enrolled for ART initiation and follow-up. Using similar recruitment procedures, a total of 120 children were enrolled in each of retrospective and prospective cohorts. Replacement of participants were made in subsequent years based on lost follow up and death rates to maintain adequacy of the sample to be followed-up.Achievements: Between January 2005 and August 2013 a total of 4,339 patients were followed for a median of 41.6 months and data on demographic characteristics, baseline and ongoing clinical features, hospitalization history, medication and laboratory information were collected. 39,762 aliquots and 25,515 specimens of plasma and dry-blood-spots respectively were obtained and stored longitudinally from October 2009 to August 2013. The project created a research platform for researchers, policy and decision makers. Moreover, it encouraged local and international investigators to identify and answer clinically and programmatically relevant research questions using the available data and specimens. Calls for concept notes paired with multiple trainings to stimulate investigators to conduct analyses further boosted the potential for doing research.Conclusions: A comprehensive and resourceful mechanism for scientific inquiry was established to support the national HIV/ART program. With meaningful involvement and defined roles, establishment of a study, which involved multiple institutions and investigators, was possible. Since ACM is the largest multi-site clinical cohort of patients on antiretroviral treatment in Ethiopia---which can be used for research and for improving clinical management---considering options to sustain the project is crucial. Key Words: Ethiopia, HIV clinical cohort, Antiretroviral therapy, Establishing Longitudinal Cohort Study, ART Monitoring and Evaluatio

    Understanding the factors affecting attrition and intention to leave of health extension workers: a mixed methods study in Ethiopia.

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    BACKGROUND: The Health Extension Program (HEP) is Ethiopia's flagship community health program, launched in 2003. Health Extension Workers (HEWs) are key vehicles for the delivery of the HEP. While it is believed that there is high attrition among HEWs, the magnitude of or reasons for attrition is unknown. Their intention to leave their jobs in the next 5 years has also never been investigated on a national scale. This study aimed to assess the magnitude of, and factors affecting HEWs' attrition and intention to leave in Ethiopia. METHODS: The study used mixed methods to address the research objectives. Using stratified random sampling and regions as strata, 85 districts from nine regions were randomly selected in Ethiopia. Within each study district, six kebeles (village clusters) were randomly selected, and all HEWs working in these kebeles were interviewed to capture their 5-year intention to leave. The study team developed a data-extraction tool for a rapid review of district-level documents covering the period June 30, 2004 through June 30, 2019 to gather their attrition figures. We used survival analysis to model attrition data and checked model goodness-of-fit using the Cox-Snell residual test. We additionally collected qualitative data from HEWs who had left their positions. RESULTS: The attrition of HEWS over the lifespan of the HEP was 21.1% (95% CI 17.5-25.3%), and the median time to exit from HEWs workforce was 5.8 years. The incidence rate was 3.1% [95% CI 2.8-3.4]. The risk of attrition was lower amongst HEWs with level four certifications, with children, and among those working in urban settings. By contrast, HEWs who were not certified with a certificate of competency (COC), who were deployed after 2008, and those who were diploma/degree holders were more likely to exit the HEWs workforce. The magnitude of intention to leave was 39.5% (95% CI 32.5-47%) and the primary reasons to leave were low incentives, dearth of career development opportunities (50.8%), high workload (24.2%), and other psychosocial factors (25%). CONCLUSION: Although the magnitude of attrition is not worryingly high, we see high magnitude in HEWs' intention to leave, indicating a dissatisfied workforce. Multiple factors have contributed to attrition and intention to leave, the prevalence of many of which can be reduced to fit the needs of this workforce and to retain them for the sustained delivery of primary healthcare in the country. Ensuring HEWs' job satisfaction is important and linked with their career development and potentially higher rates of retention

    The COVID-19 pandemic and healthcare systems in Africa:A scoping review of preparedness, impact and response

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    BACKGROUND: The COVID-19 pandemic has overwhelmed health systems in both developed and developing nations alike. Africa has one of the weakest health systems globally, but there is limited evidence on how the region is prepared for, impacted by and responded to the pandemic. METHODS: We conducted a scoping review of PubMed, Scopus, CINAHL to search peer-reviewed articles and Google, Google Scholar and preprint sites for grey literature. The scoping review captured studies on either preparedness or impacts or responses associated with COVID-19 or covering one or more of the three topics and guided by Arksey and O’Malley’s methodological framework. The extracted information was documented following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension checklist for scoping reviews. Finally, the resulting data were thematically analysed. RESULTS: Twenty-two eligible studies, of which 6 reported on health system preparedness, 19 described the impacts of COVID-19 on access to general and essential health services and 7 focused on responses taken by the healthcare systems were included. The main setbacks in health system preparation included lack of available health services needed for the pandemic, inadequate resources and equipment, and limited testing ability and surge capacity for COVID-19. Reduced flow of patients and missing scheduled appointments were among the most common impacts of the COVID-19 pandemic. Health system responses identified in this review included the availability of telephone consultations, re-purposing of available services and establishment of isolation centres, and provisions of COVID-19 guidelines in some settings. CONCLUSIONS: The health systems in Africa were inadequately prepared for the pandemic, and its impact was substantial. Responses were slow and did not match the magnitude of the problem. Interventions that will improve and strengthen health system resilience and financing through local, national and global engagement should be prioritised
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