32 research outputs found

    Cystic echinococcosis in humans and domestic animals in central Sudan:Epidemiology and molecular characterization studies

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    Cystic echinococcosis (CE) is a significant public health problem with high endemicity in east and central Africa including Sudan. Worldwide, pulmonary (pu) echinococcosis (EC) is the second to liver affection, where as in Sudan is vice versa. Ten genetic variants, or genotypes designated as (G1-G10), are distributed worldwide based on genetic diversity. (in Chapter7), we investigated molecular diversity of Echinococcus granulosus isolates collected from human clinical samples removed surgically from lung using mitochondrial gene nad1 in Sudan. It can be concluded that the pul echinococcosis in Sudan are caused by genotype 6 (G6) camel strain of E. granulosus. To improve management knowledge, attitudes and practices in human population has been conducted in quest, section III (Chapter 8). Since the level of knowledge has been found to be poor, hence is the need for the One Health approach to prevent EC. In Section IV, a cross sectional study was conducted among residents of Khartoum State in Central Sudan to determine the prevalence of CE (Chapter 9).The present investigations was conducted to improve the diagnostic potential including sequencing and phylogenetic analysis as well as LAMP and Realtime PCR .We gave an overview on the prevalent species or strains of Echinococcus granulosus in sub-Saharan Africa, treatment and preventive strategies.(Chapter 2).Part of our research was conducted in Tamboul, Central Sudan to determine the prevalence of CE genotypes and the result indicates that for the first time circulation of E. ortleppi, the cattle genotype (G5) in camel (Chapter 3) as well as G1 in Cattles (Chapter 6)

    Comparison between the BACTEC MGIT 960 system and the agar proportion method for susceptibility testing of multidrug resistant tuberculosis strains in a high burden setting of South Africa

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    BACKGROUND: The increasing problem of multi-drug-resistant (MDR) tuberculosis (TB) [ie resistant to at least isoniazid (INH) and rifampicin (RIF)] is becoming a global problem. Successful treatment outcome for MDR-TB depends on reliable and accurate drug susceptibility testing of first-line and second-line anti-TB drugs. METHOD: Consecutive M. tuberculosis isolates identified as MDR-TB during August 2007 to January 2008 using the BACTEC MGIT 960 systems and the agar proportion method were included in this study. Susceptibility testing of MDR-TB isolates against ethambutol (EMB) and streptomycin (STR) as well as two second-line anti-TB drugs, kanamycin (KAN) and ofloxacin (OFX) was performed using the BACTEC MGIT 960 systems at a routine diagnostic laboratory. The results were compared to those obtained by the agar proportion method. RESULT: The agreement between the BACTEC MGIT 960 system and the agar proportion method was 44% for EMB, 61% for STR and 89% for both KAN and OFX. The sensitivity and specificity of the BACTEC MGIT 960 system using the agar proportion method as a gold standard was 92% and 37% for EMB, 95% and 37% for STR, 27% and 97% for KAN and 84% and 90% for OFX, respectively. CONCLUSIONS: The BACTEC MGIT 960 system showed acceptable sensitivity for EMB, STR, and OFX; however, the BACTEC MGIT 960 system was less specific for EMB and STR and demonstrated a low sensitivity for KAN. The lower agreement found between the two methods suggests the unreliability of the BACTEC MGIT 960 system for the drugs tested. The reasons for the lower agreement between the two methods need to be investigated and further studies are needed in this setting to confirm the study finding.The project was supported by a grant from the NHLS.http://www.biomedcentral.com/1471-2334/12/369am2013ay201

    Molecular characterization and second-line antituberculosis drug resistance patterns of multidrug-resistant mycobacterium tuberculosis isolates from the Northern Region of South Africa

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    Despite South Africa being one of the high-burden multidrug-resistant tuberculosis (MDR-TB) countries, information regarding the population structure of drug-resistant Mycobacterium tuberculosis strains is limited from many regions of South Africa. This study investigated the population structure and transmission patterns of drug-resistant M. tuberculosis isolates in a highburden setting of South Africa as well as the possible association of genotypes with drug resistance and demographic characteristics. A total of 336 consecutive MDR-TB isolates from four provinces of South Africa were genotyped using spoligotyping and mycobacterial interspersed repetitive-unit–variable number tandem repeat (MIRU-VNTR) typing. Drug susceptibility testing for ofloxacin, kanamycin, and capreomycin was performed using the agar proportion method. The results showed that 4.8% of MDR-TB isolates were resistant to ofloxacin, 2.7% were resistant to kanamycin, and 4.5% were resistant to capreomycin, while 7.1% were extensively drug resistant (XDR), and the remaining 83.6% were susceptible to all of the second-line drugs tested. Spoligotyping grouped 90.8% of the isolates into 25 clusters, while 9.2% isolates were unclustered. Ninety-one percent of the 336 isolates were assigned to 21 previously described shared types, with the Beijing family being the predominant genotype in the North-West and Limpopo Provinces, while the EAI1_SOM family was the predominant genotype in the Gauteng and Mpumalanga Provinces. No association was found between genotypes and specific drug resistance patterns or demographic information. The high level of diversity and the geographical distribution of the drug-resistant M. tuberculosis isolates in this study suggest that the transmission of TB in the study settings is not caused by the clonal spread of a specific M. tuberculosis strain.http://jcm.asm.org/am2013ay201

    Multivariable regression analysis in Schistosoma mansoni-infected individuals in the Sudan reveals unique immunoepidemiological profiles in uninfected, egg+ and non-egg+ infected individuals

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    Background: In the Sudan, Schistosoma mansoni infections are a major cause of morbidity in schoolaged children and infection rates are associated with available clean water sources. During infection, immune responses pass through a Th1 followed by Th2 and Treg phases and patterns can relate to different stages of infection or immunity. Methodology: This retrospective study evaluated immunoepidemiological aspects in 234 individuals(range 4–85 years old) from Kassala and Khartoum states in 2011. Systemic immune profiles(cytokines and immunoglobulins) and epidemiological parameters were surveyed in n = 110 persons presenting patent S. mansoni infections (egg+), n = 63 individuals positive for S. mansoni via PCR in sera but egg negative (SmPCR+) and n = 61 people who were infection-free (Sm uninf). Immunoepidemiological findings were further investigated using two binary multivariable regression analysis. Principal Findings: Nearly all egg+ individuals had no access to latrines and over 90% obtained water via the canal stemming from the Atbara River. With regards to age, infection and an egg+ status was linked to young and adolescent groups. In terms of immunology, S. mansoni infection per se was strongly associated with increased SEA-specific IgG4 but not IgE levels. IL-6, IL-13 and IL-10 were significantly elevated in patently-infected individuals and positively correlated with egg load. In contrast, IL-2 and IL-1β were significantly lower in SmPCR+ individuals when compared to Sm uninf and egg+ groups which was further confirmed during multivariate regression analysis. Conclusions/Significance: Schistosomiasis remains an important public health problem in the Sudan with a high number of patent individuals. In addition, SmPCR diagnostics revealed another cohort of infected individuals with a unique immunological profile and provides an avenue for future studies on non-patent infection states. Future studies should investigate the downstream signalling pathways/mechanisms of IL-2 and IL-1β as potential diagnostic markers in order to distinguish patent from non-patent individuals

    Burden of disease scenarios for 204 countries and territories, 2022–2050: a forecasting analysis for the Global Burden of Disease Study 2021

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    Background: Future trends in disease burden and drivers of health are of great interest to policy makers and the public at large. This information can be used for policy and long-term health investment, planning, and prioritisation. We have expanded and improved upon previous forecasts produced as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) and provide a reference forecast (the most likely future), and alternative scenarios assessing disease burden trajectories if selected sets of risk factors were eliminated from current levels by 2050. Methods: Using forecasts of major drivers of health such as the Socio-demographic Index (SDI; a composite measure of lag-distributed income per capita, mean years of education, and total fertility under 25 years of age) and the full set of risk factor exposures captured by GBD, we provide cause-specific forecasts of mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) by age and sex from 2022 to 2050 for 204 countries and territories, 21 GBD regions, seven super-regions, and the world. All analyses were done at the cause-specific level so that only risk factors deemed causal by the GBD comparative risk assessment influenced future trajectories of mortality for each disease. Cause-specific mortality was modelled using mixed-effects models with SDI and time as the main covariates, and the combined impact of causal risk factors as an offset in the model. At the all-cause mortality level, we captured unexplained variation by modelling residuals with an autoregressive integrated moving average model with drift attenuation. These all-cause forecasts constrained the cause-specific forecasts at successively deeper levels of the GBD cause hierarchy using cascading mortality models, thus ensuring a robust estimate of cause-specific mortality. For non-fatal measures (eg, low back pain), incidence and prevalence were forecasted from mixed-effects models with SDI as the main covariate, and YLDs were computed from the resulting prevalence forecasts and average disability weights from GBD. Alternative future scenarios were constructed by replacing appropriate reference trajectories for risk factors with hypothetical trajectories of gradual elimination of risk factor exposure from current levels to 2050. The scenarios were constructed from various sets of risk factors: environmental risks (Safer Environment scenario), risks associated with communicable, maternal, neonatal, and nutritional diseases (CMNNs; Improved Childhood Nutrition and Vaccination scenario), risks associated with major non-communicable diseases (NCDs; Improved Behavioural and Metabolic Risks scenario), and the combined effects of these three scenarios. Using the Shared Socioeconomic Pathways climate scenarios SSP2-4.5 as reference and SSP1-1.9 as an optimistic alternative in the Safer Environment scenario, we accounted for climate change impact on health by using the most recent Intergovernmental Panel on Climate Change temperature forecasts and published trajectories of ambient air pollution for the same two scenarios. Life expectancy and healthy life expectancy were computed using standard methods. The forecasting framework includes computing the age-sex-specific future population for each location and separately for each scenario. 95% uncertainty intervals (UIs) for each individual future estimate were derived from the 2·5th and 97·5th percentiles of distributions generated from propagating 500 draws through the multistage computational pipeline. Findings: In the reference scenario forecast, global and super-regional life expectancy increased from 2022 to 2050, but improvement was at a slower pace than in the three decades preceding the COVID-19 pandemic (beginning in 2020). Gains in future life expectancy were forecasted to be greatest in super-regions with comparatively low life expectancies (such as sub-Saharan Africa) compared with super-regions with higher life expectancies (such as the high-income super-region), leading to a trend towards convergence in life expectancy across locations between now and 2050. At the super-region level, forecasted healthy life expectancy patterns were similar to those of life expectancies. Forecasts for the reference scenario found that health will improve in the coming decades, with all-cause age-standardised DALY rates decreasing in every GBD super-region. The total DALY burden measured in counts, however, will increase in every super-region, largely a function of population ageing and growth. We also forecasted that both DALY counts and age-standardised DALY rates will continue to shift from CMNNs to NCDs, with the most pronounced shifts occurring in sub-Saharan Africa (60·1% [95% UI 56·8–63·1] of DALYs were from CMNNs in 2022 compared with 35·8% [31·0–45·0] in 2050) and south Asia (31·7% [29·2–34·1] to 15·5% [13·7–17·5]). This shift is reflected in the leading global causes of DALYs, with the top four causes in 2050 being ischaemic heart disease, stroke, diabetes, and chronic obstructive pulmonary disease, compared with 2022, with ischaemic heart disease, neonatal disorders, stroke, and lower respiratory infections at the top. The global proportion of DALYs due to YLDs likewise increased from 33·8% (27·4–40·3) to 41·1% (33·9–48·1) from 2022 to 2050, demonstrating an important shift in overall disease burden towards morbidity and away from premature death. The largest shift of this kind was forecasted for sub-Saharan Africa, from 20·1% (15·6–25·3) of DALYs due to YLDs in 2022 to 35·6% (26·5–43·0) in 2050. In the assessment of alternative future scenarios, the combined effects of the scenarios (Safer Environment, Improved Childhood Nutrition and Vaccination, and Improved Behavioural and Metabolic Risks scenarios) demonstrated an important decrease in the global burden of DALYs in 2050 of 15·4% (13·5–17·5) compared with the reference scenario, with decreases across super-regions ranging from 10·4% (9·7–11·3) in the high-income super-region to 23·9% (20·7–27·3) in north Africa and the Middle East. The Safer Environment scenario had its largest decrease in sub-Saharan Africa (5·2% [3·5–6·8]), the Improved Behavioural and Metabolic Risks scenario in north Africa and the Middle East (23·2% [20·2–26·5]), and the Improved Nutrition and Vaccination scenario in sub-Saharan Africa (2·0% [–0·6 to 3·6]). Interpretation: Globally, life expectancy and age-standardised disease burden were forecasted to improve between 2022 and 2050, with the majority of the burden continuing to shift from CMNNs to NCDs. That said, continued progress on reducing the CMNN disease burden will be dependent on maintaining investment in and policy emphasis on CMNN disease prevention and treatment. Mostly due to growth and ageing of populations, the number of deaths and DALYs due to all causes combined will generally increase. By constructing alternative future scenarios wherein certain risk exposures are eliminated by 2050, we have shown that opportunities exist to substantially improve health outcomes in the future through concerted efforts to prevent exposure to well established risk factors and to expand access to key health interventions

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Cystic echinococcosis in humans and domestic animals in central Sudan:Epidemiology and molecular characterization studies

    No full text
    Cystic echinococcosis (CE) is a significant public health problem with high endemicity in east and central Africa including Sudan. Worldwide, pulmonary (pu) echinococcosis (EC) is the second to liver affection, where as in Sudan is vice versa. Ten genetic variants, or genotypes designated as (G1-G10), are distributed worldwide based on genetic diversity. (in Chapter7), we investigated molecular diversity of Echinococcus granulosus isolates collected from human clinical samples removed surgically from lung using mitochondrial gene nad1 in Sudan. It can be concluded that the pul echinococcosis in Sudan are caused by genotype 6 (G6) camel strain of E. granulosus. To improve management knowledge, attitudes and practices in human population has been conducted in quest, section III (Chapter 8). Since the level of knowledge has been found to be poor, hence is the need for the One Health approach to prevent EC. In Section IV, a cross sectional study was conducted among residents of Khartoum State in Central Sudan to determine the prevalence of CE (Chapter 9).The present investigations was conducted to improve the diagnostic potential including sequencing and phylogenetic analysis as well as LAMP and Realtime PCR .We gave an overview on the prevalent species or strains of Echinococcus granulosus in sub-Saharan Africa, treatment and preventive strategies.(Chapter 2).Part of our research was conducted in Tamboul, Central Sudan to determine the prevalence of CE genotypes and the result indicates that for the first time circulation of E. ortleppi, the cattle genotype (G5) in camel (Chapter 3) as well as G1 in Cattles (Chapter 6)

    Landslide Susceptibility Screening using Wind-Driven Rainfall

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    Rainfall is one of the most significant triggering factors for shallow landslides, raveling, and erosion of over-steepened slopes, especially in steeply inclined mountainous regions, such as the western Greater Himalayan Mountains of northern Pakistan. The influence of wind-driven rainfall is usually neglected in comparisons between rainfall and mass wasting. Winddriven rain falls with an angle of incidence influenced by prevailing wind direction and velocity. The need to include considerations of incident rainfall distribution with respect to mass wasting processes is long overdue. The idea of coupling wind-driven rainfall based on directional monsoon with regional topography (slope aspect) was analyzed to ascertain the actual distribution of rainfall upon slopes exhibiting varying inclinations and slope aspect. Regional-level landslide susceptibility maps were prepared for the entire Indus River watershed using widely accepted methods including GIS heuristic weighted overlay and fuzzy logic techniques by including traditional rainfall distribution maps as one of the triggering factors. The results of that analysis were then compared with current research to examine whether an oblique/ inclined rainfall correction map would aid in assessing landslide susceptibility by considering the impacts of slope inclination and aspect on the effective rainfall being caught by those slopes facing the prevailing wind directions. The susceptibility maps produced bythis method were found to be more reasonable than others yet produced of such a large study area (~75,000 km2)

    Historic Landslide Dams along the Upper Indus River, Northern Pakistan

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    A significant number of landslides have occurred along the upper Indus River which resulted in temporary landslide dams. All of these debris dams eventually breach, often causing catastrophic flooding downstream. Remote sensing data can aid in the recognition of many of these features in otherwise inaccessible areas. Regional level landslide inventory maps have recently been prepared, which also show the locations of historic landslide dams. The research reported in this paper was a reconnaissance-level study, aimed at identifying those slides and rock avalanches that are or were more than 500-m long, crossing at least five adjacent contours. Representative examples of the various types of landslides were evaluated using topographic expression, aided by field reconnaissance and literature review. Many of the landslide features described in the study area exceed an entrained debris volume of 10 million m3, which are often described as mega landslides like the Gol-Gone, Satpara, and Katzarah rockslide dams. Cross canyon profiles were also prepared of selected landslides to estimate the likely block kinematics controlling the slopes failure, using the three-dimensional analyst extension of common computer software. The majority of the historic mega landslide events appear to be seismically triggered. The research reported in this paper suggests that the highest concentration of landslide dams were observed in the tectonically active Nanga Perbat Haramosh Massif region, where the river flows through narrow gorges, and/or where active thrust faults cross the river. Most of these features appear to be structurally controlled, translating along suites of planar preexisting discontinuities, such as bedding, jointing, foliation, lithologic contacts, shear zones, or faults. These features often form landslide dams if they empty into perennial river channels and often leave telltale signs of their short-lived existence. These signs include elevated stream terraces, lacustrine deposits (within and upstream of the temporary blockages), local sediment fans which form about the margins of short-lived reservoirs, deeply incised gorges, and scattered outbreak flood debris along the flanks of the river channel, often blocking side canyon tributaries. If infrastructure, such as highways, pipelines, or transmission lines were to be constructed into the study area, the landslide features should merit additional study and field verification to ascertain the validity of the interpreted features
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