Sero-epidemiological study on Maedi-Visna in selected areas of Ethiopia

The study was conducted to verify the existence of Maedi-Visna virus infection (Ovine Progressive Pneumonia- OPP) in exotic sheep breed in selected areas of Ethiopia. ELISA and Hematoxylin & Eosin (HE) staining techniques were employed to examine the serum and tissue samples respectively. ELISA test of serum samples showed 88%, 19%, 10%, 6%, and 0.8% infection rate for Debre Berhan sheep breeding center, and Arsi, Bale, North Omo and Gurage zones respectively. At necropsy 11% (4/36) of the sheep examined had characteristic gross pathological lung lesions of Maedi/OPP and 33% (12/36) indicated the presence of the disease through histopathological examinations. The major histopathological findings were peribronchial and interstitial lymphocytic infiltrations and/or follicle-like aggregations, interstitial connective tissue proliferation, hyperplasia of the smooth muscles in the ducts of terminal bronchioles and alveoli. The present findings provide a clear evidence for the dissemination of Maedi-Visna virus following the distribution of exotic rams from the breeding and multiplication center. Therefore, survey in other areas is also required to have broad picture of the disease in the country which will help to design a practical control strategy of the disease at the national level. Keywords: Ethiopia, exotic sheep breeds, maedi-visna, sero-epidemiolog

Utilization and Determinants of Postnatal Care Services in Ethiopia: A Systematic Review and Meta-Analysis

BACKGROUND: Postnatal care use is vital in saving mother and newborn lives which is a continuum of care for maternal, neonatal and child health. This reviewaimed to determine the utilization and determinants of postnatal care use in Ethiopia.METHODS: PubMed, Scopus, Web of Science, and Embase databases were searched on June 25, 2017. The study screening, data extraction and quality assessment were done independently by two reviewers. Effect sizes were pooled using a random-effectsmodel.RESULTS: Nine articles were included in the review. The pooled estimate for utilization of the service was 32% (95% CI: 21%, 43%). The pooled results of determinants of postnatal care use was statistically significant among those mothers who had ability to make decisions (1.89; 1.25, 2.54), had a history of antenatal care utilization (2.55; 1.42, 3.68), received more than two antenatal care visits (1.84; 1.28, 2.40), and received the service from skilled service provider (3.16; 1.62, 4.70). It was also found that mothers who gave birth in health faciliteis (2.13; 1.14, 3.12), had middle monthly income, richer, were from urban areas, and had knowledge of obstetric danger signs were significantly associated with increased odds of postnatal care use.CONCLUSION: Utilization of the services is low in Ethiopia. Antenatal care utilization, skilled service provider, being from urban area and delivery in health facility had a significant effect on postnatal care utilization. More rigorous studies are needed to identify determinant with the causal association to postnatal care utilization. The review was registered on PROSPEROCRD42017060266

Impact of Exchange Rate Regime on International Tourists’ Inflow in South Africa

Globally, research on exchange rate regimes have mainly centred on their influences on international trade flows, foreign direct investment, and economic growth while the empirical nexus between exchange rate regimes and international tourists’ inflow has been scarcely explored in South Africa. The country has consistently witnessed an increasing inflow of tourists since the 1990s to date, hence, the importance of international tourism inflow in South Africa cannot be overemphasised as it has implications on the economy, employment generation, and as a source of revenue. Also, the nexus between the exchange rate regime and international tourism inflow in South Africa has not garnered sufficient empirical attention. Therefore, this research investigates the impact of the exchange rate regime on international tourists’ inflow in South Africa over the period 1990 to 2020. Secondary data on the international tourists’ receipt, GDP income per capita, inflation rate, and exchange rate were derived from the World Bank Development Indicators while the binary variable is used as a measure of the exchange rate regime. The collected data was analysed using the ordinary least squares (OLS). Findings from the study reveal that the existing floating exchange rate regime supports the international tourists’ inflow, but its significant impact as a major driver of inflow is yet to be felt in South Africa. The study, however, established that per capita GDP and domestic exchange rate depreciation significantly promote international tourists’ inflow in the country

Mitochondrial phylogeography and population structure of the cattle tick Rhipicephalus appendiculatus in the African Great Lakes region

Abstract Background The ixodid tick Rhipicephalus appendiculatus is the main vector of Theileria parva, wich causes the highly fatal cattle disease East Coast fever (ECF) in sub-Saharan Africa. Rhipicephalus appendiculatus populations differ in their ecology, diapause behaviour and vector competence. Thus, their expansion in new areas may change the genetic structure and consequently affect the vector-pathogen system and disease outcomes. In this study we investigated the genetic distribution of R. appendiculatus across agro-ecological zones (AEZs) in the African Great Lakes region to better understand the epidemiology of ECF and elucidate R. appendiculatus evolutionary history and biogeographical colonization in Africa. Methods Sequencing was performed on two mitochondrial genes (cox1 and 12S rRNA) of 218 ticks collected from cattle across six AEZs along an altitudinal gradient in the Democratic Republic of Congo, Rwanda, Burundi and Tanzania. Phylogenetic relationships between tick populations were determined and evolutionary population dynamics models were assessed by mismach distribution. Results Population genetic analysis yielded 22 cox1 and 9 12S haplotypes in a total of 209 and 126 nucleotide sequences, respectively. Phylogenetic algorithms grouped these haplotypes for both genes into two major clades (lineages A and B). We observed significant genetic variation segregating the two lineages and low structure among populations with high degree of migration. The observed high gene flow indicates population admixture between AEZs. However, reduced number of migrants was observed between lowlands and highlands. Mismatch analysis detected a signature of rapid demographic and range expansion of lineage A. The star-like pattern of isolated and published haplotypes indicates that the two lineages evolve independently and have been subjected to expansion across Africa. Conclusions Two sympatric R. appendiculatus lineages occur in the Great Lakes region. Lineage A, the most diverse and ubiquitous, has experienced rapid population growth and range expansion in all AEZs probably through cattle movement, whereas lineage B, the less abundant, has probably established a founder population from recent colonization events and its occurrence decreases with altitude. These two lineages are sympatric in central and eastern Africa and allopatric in southern Africa. The observed colonization pattern may strongly affect the transmission system and may explain ECF endemic instability in the tick distribution fringes

Prevalence of long COVID-19 among healthcare workers: a systematic review and meta-analysis protocol

Introduction A proportion of those who survive the acute phase of COVID-19 experience prolonged symptoms, commonly known as long COVID-19. Given that healthcare workers (HCWs) face an elevated risk of acute COVID-19 compared with the general population, the global burden of long COVID-19 in HCWs is likely to be large; however, there is limited understanding of the prevalence of long COVID-19 in HCWs, or its symptoms and their clustering. This review will aim to estimate the pooled prevalence and the symptoms of long COVID-19 among HCWs infected with SARS-CoV-2 globally, and investigate differences by country, age, sex, ethnicity, vaccination status and occupation. Methods and analysis A systematic review and meta-analysis will be conducted. Medline (via Ovid), CINAHL (via EBSCO), Embase (via Ovid), PsycINFO (via EBSCO),OpenGrey(grey literature) andmedRxiv(preprint server) will be searched from the 31 December 2019 onward. All research studies and preprint articles reporting any primary data on the prevalence and/or the symptoms of long COVID-19 among adult HCWs will be included. Methodological quality will be assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Outcomes are anticipated to be the prevalence of long COVID-19 among HCWs around the world and trajectory of symptoms. Data synthesis will include random-effect meta-analysis for studies reporting prevalence data of long COVID-19 following SARS-CoV-2 infection among HCWs. The results will be presented with a 95% CI as an estimated effect across studies. Heterogeneity will be assessed using I² statistic. Where meta-analysis is inappropriate, a narrative synthesis of the evidence will be conducted. Ethics and dissemination Ethical approval is not needed as data will be obtained from published articles. We will publish our findings in a peer-reviewed journal and disseminate the results of our review at conferences. PROSPERO registration number CRD42022312781

Features of modeling fatty liver disease in rats of different ages based on a high-calorie diet

BACKGROUND: The problem of diagnosis, treatment and prevention of fat liver disease (FLD) is one of the actual problems of modern medicine. In this regard, the need for the creation of reliable experimental models of the FLD, which would be as close as possible to the pathogenetic patterns of the development of this disease in humans.AIM: To create an experimental model of FLD and compare the efficiency of its reproduction in rats of different ages.MATERIALS AND METHODS: The study was conducted on male Wistar rats, whose ages at the beginning of the experiment were 3 and 18 months. Control animals were fed a standard diet. The experimental rats were kept on a diet with excess fat (45 %) and carbohydrates (31 %) for 12 weeks. The liver tissue samples were taken for morphological studies of FLD. Histological preparations were made according to the standard technique. Morphometry on digital images of micropreparations was conducted using the computer program «IMAGE J». The concentration of lipids, cholesterol, and triglecerides in the liver tissue was determined, and the concentration of ALT in the blood serum was determined. To assess the biophysical properties of the liver tissue, the method of multifrequency bioimpedance measurement was used.RESULTS: The transfer of animals to a high-calorie diet developed by us led to the development of FLD. This was evidenced by an increase of the liver mass, its pale shade and soft consistency. Morphometric signs of FLD were also revealed. Hypertrophy of hepatocytes was observed with a simultaneous decrease in the nuclear-cytoplasmic ratio; accumulation of numerous lipid inclusions in the cytoplasm and the appearance of large lipid droplets replacing the voids of dead hepatocytes. The number of binuclear hepatocytes and nucleolus in the nucleus, the relative area of the sinusoid network were decreased. An increase in the concentration of lipids, cholesterol and triglecerides in the liver tissue of experimental rats, as well as the activity of ALT in the blood serum, was observed. Changes in the bioimpedance measurements of the liver tissue also indicated the  development of severe fatty degeneration of the liver in both young (to a greater extent) and old rats.CONCLUSION: The model of FLD we have advanced based on a combined (fat-carbohydrate) high-calorie diet. It leads to the development of pronounced morphological, biochemical and biophysical signs of this pathology in all experimental rats. The most pronounced manifestations of FLD are observed in young animals

Management\u27s Perspective on Critical Success Factors Affecting Mobile Learning in Higher Education Institutions - An Empirical Study

Mobile learning (m-Learning) is considered to be one of the fastest growing learning platforms. The immense interest in m-Learning is attributed to the incredible rate of growth of mobile technology and its proliferation into every aspect of modern life. Despite this, m-Learning has not experienced a similar adoption rate in the education sector, chiefly higher education. Researchers have attempted to explain this anomaly by conducting several studies in the area. However, mostly the research in m-Learning is examined from the perspective of the students and educators. In this research, it is contended that there is a third important stakeholder group whose opinion is equally important in determining the success of m-Learning: the university management. Although diversified by nature, heads of departments, deans, and information technology system administrators are nevertheless considered members of any university management. The results of the research show that university commitment to m-Learning, university learning practices, and change management practices were the factors critical to the success of m-Learning, from the university management perspective