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Pathways to care for patients with type 2 diabetes and HIV/ AIDS comorbidities in Soweto, South Africa: An ethnographic study
No full textBackground: South Africa is experiencing colliding epidemics of HIV/AIDS and noncommunicable diseases. In response, the National Department of Health has implemented integrated chronic disease management aimed at strengthening primary health care (PHC) facilities to manage chronic illnesses. However, chronic care is still fragmented. This study explored how the health system functions to care for patients with comorbid type 2 diabetes (T2DM) and HIV/AIDS at a tertiary hospital in Soweto, South Africa.
Methods: We employed ethnographic methods encompassing clinical observations and qualitative interviews with health care providers at the hospital (n=30). Data were transcribed verbatim and thematically analyzed using QSR NVivo 12 software.
Findings: Health systemic challenges such as the lack of medication, untrained nurses, and a limited number of doctors at PHC clinics necessitated patient referrals to a tertiary hospital. At the hospital, patients with T2DM were managed first at the medical outpatient clinic before they were referred to a specialty clinic. Those with comorbidities attended different clinics at the hospital partly due to the structure of the tertiary hospital that offers specialized care. In addition, little to no collaboration occurred among health care providers due to poor communication, noncentralized patient information, and staff shortage. As a result, patients experienced disjointed care.
Conclusion: PHC clinics in Soweto need to be strengthened by training nurses to diagnose and manage patients with T2DM and also by ensuring adequate medical supplies. We recommend that the medical outpatient clinic at a tertiary hospital should also be strengthened to offer integrated and collaborative care to patients with T2DM and other comorbidities. Addressing key systemic challenges such as staff shortages and noncentralized patient information will create a patient-centered as opposed to disease-specific approach to care.The South African Medical Research Council funded this study from the core grant to DPHRU (SHNS017-NORRIS S MRC 2017-NORRIS S MRC 2017)
Efficacy of the ChAdOx1 nCoV-19 Covid-19 vaccine against the B.1.351 variant
Get PDFBackground: Assessment of the safety and efficacy of vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in different populations is essential, as is investigation of the efficacy of the vaccines against emerging SARS-CoV-2 variants of concern, including the B.1.351 (501Y.V2) variant first identified in South Africa.
Methods: We conducted a multicenter, double-blind, randomized, controlled trial to assess the safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) in people not infected with the human immunodeficiency virus (HIV) in South Africa. Participants 18 to less than 65 years of age were assigned in a 1:1 ratio to receive two doses of vaccine containing 5×1010 viral particles or placebo (0.9% sodium chloride solution) 21 to 35 days apart. Serum samples obtained from 25 participants after the second dose were tested by pseudovirus and live-virus neutralization assays against the original D614G virus and the B.1.351 variant. The primary end points were safety and efficacy of the vaccine against laboratory-confirmed symptomatic coronavirus 2019 illness (Covid-19) more than 14 days after the second dose.
Results: Between June 24 and November 9, 2020, we enrolled 2026 HIV-negative adults (median age, 30 years); 1010 and 1011 participants received at least one dose of placebo or vaccine, respectively. Both the pseudovirus and the live-virus neutralization assays showed greater resistance to the B.1.351 variant in serum samples obtained from vaccine recipients than in samples from placebo recipients. In the primary end-point analysis, mild-to-moderate Covid-19 developed in 23 of 717 placebo recipients (3.2%) and in 19 of 750 vaccine recipients (2.5%), for an efficacy of 21.9% (95% confidence interval [CI], -49.9 to 59.8). Among the 42 participants with Covid-19, 39 cases (95.1% of 41 with sequencing data) were caused by the B.1.351 variant; vaccine efficacy against this variant, analyzed as a secondary end point, was 10.4% (95% CI, -76.8 to 54.8). The incidence of serious adverse events was balanced between the vaccine and placebo groups.
Conclusions: A two-dose regimen of the ChAdOx1 nCoV-19 vaccine did not show protection against mild-to-moderate Covid-19 due to the B.1.351 variant. (Funded by the Bill and Melinda Gates Foundation and others; ClinicalTrials.gov number, NCT04444674; Pan African Clinical Trials Registry number, PACTR202006922165132)
Overlap in genetic risk for cross-disorder vulnerability to mental disorders and genetic risk for altered subcortical brain volumes
No full textBackground: There have been considerable recent advances in understanding the genetic architecture of psychiatric disorders as well as the underlying neurocircuitry. However, there is little work on the concordance of genetic variations that increase risk for cross-disorder vulnerability, and those that influence subcortical brain structures. We undertook a genome-wide investigation of the genetic overlap between cross-disorder vulnerability to psychiatric disorders (p-factor) and subcortical brain structures.
Methods: Summary statistics were obtained from the PGC cross-disorder genome-wide association study (GWAS) (Ncase= 232,964, Ncontrol= 494,162) and the CHARGE-ENIGMA subcortical brain volumes GWAS (N=38,851). SNP effect concordance analysis (SECA) was used to assess pleiotropy and concordance. Linkage Disequilibrium (LD) Score Regression and ρ-HESS were used to assess genetic correlation and conditional false discovery (cFDR) was used to identify variants associated with p-factor, conditional on the variants association with subcortical brain volumes.
Results: Evidence of global pleiotropy between p-factor and all subcortical brain regions was observed. Risk variants for p-factor correlated negatively with brainstem. A total of 787 LD-independent variants were significantly associated with p-factor when conditioned on the subcortical GWAS results. Gene set enrichment analysis of these variants implicated actin binding and neuronal regulation.
Limitations: SECA could be biased due to the potential presence of overlapping study participants in the p-factor and subcortical GWASs.
Conclusion: Findings of genome-wide pleiotropy and possible concordance between genetic variants that contribute to p-factor and smaller brainstem volumes, are consistent with previous work. cFDR results highlight actin binding and neuron regulation as key underlying mechanisms. Further fine-grained delineation of these mechanisms is needed to advance the field
Viruses, variants and vaccines
No full textThe current SARS-CoV-2 pandemic has brought a number of major global clinical, sociological and economic issues into sharp focus. We address some of these issues, focusing on short-term factors such as virus mutations and vaccine efficacy, and also considering the longer-term implications of the current pandemic. We discuss societal responses to the presence of a pathogen that will probably remain in circulation for decades or longer, and to future new emergent viruses.Declaration. None. Acknowledgements. The authors thank the University of Pretoria (DAC, SGB, MSP), Rhodes University (RAD) and the University of Cape Town (EPR, A-LW) for institutional support, and the South African Medical Research Council (MSP, RAD) and the National Research Foundation for financial support
Economic growth as an underlying probable systemic driver for childhood obesity in South Africa: A Joinpoint regression and ecological analysis over 10 years
Get PDFBackground: Childhood obesity has become a global public health problem and is a known risk factor for type 2 diabetes, cardiovascular disease, hypertension, stroke, myocardial infarction and various cancers in later adulthood.Associations between adult obesity and economic growth, technological changes, socioeconomic status and economic inequities have been reported, but limited data are available for children and adolescents in countries that are undergoing an epidemiological health transition exhibiting both under- and overnutrition.
Objectives: To demonstrate childhood obesity trends and explore their associations with economic growth in South Africa (SA).
Methods: This was a retrospective review and analysis of obesity and economic growth trends in SA. Data for obesity levels were obtained from national surveys conducted in SA youths in 2002, 2008 and 2012. Economic growth indicators (EGIs), namely gross domestic product (GDP) per capita, household final consumption expenditure and Gini coefficient, were obtained from the World Bank and IHS Global Insight databases. Obesity trends for 2002 - 2012 are presented by gender and ethnicity. Annual percentage changes (APCs) in obesity prevalence were computed to assess obesity trends using the linear Joinpoint regression.
Results: An overall increase in obesity prevalence over time from 3.8% to 6.0% was observed. Females had higher levels across all time points. APCs in both males (7.8%; 95% confidence interval (CI) 0.3 - 15.9; p=0.01) and females (3.1%; 95% CI -14.7 - 24.7; p=0.30) were observed. Among black Africans, coloureds and whites, females had higher obesity levels than males for the three time points. For males, the prevalence of obesity was highest in whites and Asians/Indians, whereas coloureds and blacks had lower levels across all time points. However, the black male population had the highest APC increase (9.4%; 95% CI -23.0 - 55.3; p=0.20). The prevalence of obesity was positively and inversely associated with GDP per capita and the Gini coefficient, respectively.
Conclusions: An increase in childhood and adolescent obesity over time was observed, while trend associations between obesity and EGIs exist
Evaluating chronic kidney disease in rural South Africa: Comparing estimated glomerular filtration rate using point-of-care creatinine to iohexol measured GFR
No full textObjectives: The prevalence of chronic kidney disease is rising rapidly in low- and middle-income countries. Serum creatinine and estimation of glomerular filtration rate (GFR) are critical diagnostic tools, yet access to centralised laboratory services remains limited in primary care resource-limited settings. The aim of this study was to evaluate point-of-care (POC) technologies for serum creatinine measurement and to compare their performance to a gold standard measurement using iohexol measured GFR (mGFR).
Methods: POC creatinine was measured using iSTAT® and StatSensor® devices in capillary and venous whole blood, and laboratory creatinine was measured using the compensated kinetic Jaffe method in 670 participants from a rural area in South Africa. GFR estimating equations Chronic Kidney Disease Epidemiology Collaboration and Modification of Diet in Renal Disease (CKD-EPI and MDRD) for POC and laboratory creatinine were compared to iohexol mGFR.
Results: Calculated GFR for laboratory and POC creatinine measurements overestimated GFR (positive bias of 1.9-34.1 mL/min/1.73 m2). However, all POC devices had less positive bias than the laboratory Jaffe method (1.9-14.7 vs. 34.1 for MDRD, and 8.4-19.9 vs. 28.6 for CKD-EPI). Accuracy within 30% of mGFR ranged from 0.56 to 0.72 for POC devices and from 0.36 to 0.43 for the laboratory Jaffe method. POC devices showed wider imprecision with coefficients of variation ranging from 4.6 to 10.2% compared to 3.5% for the laboratory Jaffe method.
Conclusions: POC estimated GFR (eGFR) showed improved performance over laboratory Jaffe eGFR, however POC devices suffered from imprecision and large bias. The laboratory Jaffe method performed poorly, highlighting the need for laboratories to move to enzymatic methods to measure creatinine.The South African Medical Research Council, with funds from the South African National Department of Health, MRC UK (via the Newton Fund) and GSK R&D
Role of vaccines in preventing influenza in healthy children
Get PDFThe role of an influenza vaccine is to minimise illness and death. Vaccines provide good protection against influenza strains and significantly reduce time off work. However, the recommendation for use depends on the efficacy, effectiveness and safety of the vaccines. We highlight a Cochrane review that sought to determine the efficacy, effectiveness and safety of seasonal influenza vaccines in healthy children, and provide implications for practice for vaccination of children. The findings suggest that influenza vaccines play a key role in reducing serious morbidity and mortality among children. There were few data available to provide firm conclusions on adverse events. Vaccinating against influenza not only reduces its incidence among children, but also extends these benefits to the unvaccinated population, such as the elderly. In light of the many direct and indirect benefits of vaccinating children aged 2 - 16 years, there is a need to provide access to influenza vaccines to all eligible South African children.This study was funded by the South African Medical Research Counsil
Azithromycin for COVID-19: Evidence review of the clinical benefit and harm
No full textAzithromycin is currently included in many South African standard treatment guidelines, including for the treatment of bacterial infections in penicillin-allergic patients, for rickettsial infections in patients unable to take tetracyclines, and specifically for the management of atypical bacterial infections, including nosocomial pneumonia
Availability and advertising of sugar sweetened beverages in South African public primary schools following a voluntary pledge by a major beverage company: A mixed methods study
Get PDFBackground: Towards the end of the 2017 school year, a prominent beverage company in South Africa pledged to remove their sugar-sweetened beverages (SSBs) and advertisements from primary schools in order to contribute to the realization of a healthy school environment.
Objectives: To assess the availability and advertising of the company’s beverages in public primary schools in Gauteng province following their voluntary pledge to remove the products, and to explore perceptions of school staff regarding SSB availability in schools and processes related to the implementation of the pledge.
Methods: In 2019, we conducted a representative survey of public sector primary (elementary) schools in Gauteng province, South Africa. A random sample of schools was drawn, with schools stratified by whether or not they charge fees. This was a proxy for the socioeconomic status of the locale and student body. At each school, the availability of beverages and presence of advertising or not was assessed by an observational audit tool and differences across fee status assessed by Pearson χ2
test. Semi-structured interviews were conducted with a purposive sample of school officials. Data from the interviews were coded and thematic analysis conducted.
Results: Two years following a voluntary pledge, the company’s carbonated SSBs were available for sale in 54% (CI: 45–63%) of schools with tuck shops and advertised in 31% (CI: 25–39%). Qualitative interviews revealed a complex landscape of actors within schools, which, combined with indifference or resistance to the pledge, may have contributed to the continued availability of SSBs.
Conclusions: Though we were unable to examine SSB availability before and after the pledge, our findings provide some preliminary evidence that voluntary pledges by commercial entities are not sufficient to remove SSBs and advertisements from schools. Mandatory regulations coupled with in-depth engagement with schools may be an avenue to pursue in the futureThis research was funded by the National Institute for Health Research (NIHR) (GHR:16/137/34) using UK aid from the UK Government to support global health research. The views expressed in this publication are those of the author(s) and not necessarily those of the NIHR or the UK Department of Health and Social Care. SAMRC with South African Medical Research Council. AE, NS, KJH, KL are supported by the SAMRC/Centre for Health Economics and Decision Science – PRICELESS
SA, University of Witwatersrand School of Public Health, Faculty of Health Sciences, Johannesburg South Africa