Sexual behaviour patterns in South Africa and their association with the spread of HIV: insights from a mathematical model

This paper aims to quantify the effects of different types of sexual risk behaviour on the spread of HIV in South Africa. A mathematical model is developed to simulate changes in numbers of sexual partners, changes in marital status, changes in commercial sex activity and changes in the frequency of unprotected sex over the life course. This is extended to allow for the transmission of HIV, and the model is fitted to South African HIV prevalence data and sexual behaviour data. Results suggest that concurrent partnerships and other non-spousal partnerships are major drivers of the HIV/AIDS epidemic in South Africa.AIDS/HIV, sexual behavior, simulation model, South Africa

Die Voorspellingsgeldigheid van die ESSI lees- en speltoets vir nie-moedertaal primêreskoolleerders

Graad 5 tot 7 leerders afkomstig vanuit drie Afrikataalsprekende groepe in die Vrystaat, naamlik Sesotho, isiXhosa, en Setswana, is by die studie ingesluit. Voorspellingsgeldigheid is ondersoek deur die leerders se tellings op die lees- en speltoets van die ESSI met hulle akademiese prestasie te korreleer. Hierdie korrelasies is vir die drie Afrikataalsprekers afsonderlik ondersoek. In al die gevalle is koëffisiënte van medium tot groot effekgroottes gevind. Verder het die resultate aangedui dat geen beduidende verskille in die gemiddelde lees- of speltellings vir die onderskeie taalgroepe vir elk van die onderskeie grade voorgekom het nie. Ten opsigte van die leerders se prestasie op die ESSI-toets is wel geslagsverskille gevind. Waar beduidende verskille voorgekom het, het die dogters beduidende hoër gemiddeldes as die seuns behaal.Kernwoorde: ESSI Lees- en Speltoets, voorspellingsgeldigheid, niemoedertaalsprekers en akademiese prestasieEnglish AbstractGrade 5 to 7 learners descended from three African language groups in the Free State, namely Sesotho, isiXhosa, and Setswana, were included in the study. Predictive validity was investigated by correlating the learners’ scores in the ESSI Reading and Spelling Test with their academic achievement. These correlations were done for the three African language groups separately, and in all the instances, coefficients with medium to large effect sizes were found. The results further indicated that the average achievement of learners of various language groups in a particular grade in the reading and spelling tests did not differ significantly from one another. It was also found that the two genders were indeed inclined to perform differently in the ESSI tests. Where significant differences were found, the girls obtained significantly higher average scores than the boys did.Keywords: ESSI Reading and Spelling Test, predictive validity, non-mother tongue speakers and academic achievemen

HIV/AIDS mortality trends pre and post ART for 1997 - 2012 in South Africa – have we turned the tide?

Background. South Africa (SA) has one of the largest HIV/AIDS epidemics in the world and the most extensive antiretroviral therapy (ART) programme globally, which was rolled out from 2004. This paper reports the trends in HIV/AIDS mortality pre and post ART rollout in SA. Methods. Vital registration cause-of-death data from Statistics South Africa were adjusted for under-reporting of deaths using demographic methods. Misattributed HIV/AIDS deaths were identified by regressing excess mortality on a lagged indicator HIV antenatal clinic prevalence for causes found to be associated with HIV/AIDS. Background trends in the source-cause mortality rates were estimated from the trend in cause-specific mortality experienced among 75 - 84-year-olds. Mortality rates were calculated using mid-year population estimates and the World Health Organization world standard age-weights. Results. We estimated over 3 189 000 HIV/AIDS deaths for 1997 - 2012. In 1997, 60 336 (14.5%) of deaths were attributed to HIV/AIDS; this number peaked in 2006 at 283 564 (41.9%) and decreased to 153 661 (29.1%) by 2012; female mortality rates peaked in 2005 and those of males in 2006. Men aged 35 years and older had higher mortality rates than did women. While the rates at ages below 65 years in 2012 were lower than those in 2006, rates of those age 65 years and older remained unchanged. Conclusion. The number of HIV/AIDS deaths has almost halved since the ART rollout. Of concern is the high mortality in men 45 years and older and the high mortality of men compared with women in the older ages by 2012; this gap has increased with age. Treatment and prevention programmes should strategise how to target men

Bayesian modelling of population trends in alcohol consumption provides empirically based country estimates for South Africa

Background Alcohol use has widespread effects on health and contributes to over 200 detrimental conditions. Although the pattern of heavy episodic drinking independently increases the risk for injuries and transmission of some infectious diseases, long-term average consumption is the fundamental predictor of risk for most conditions. Population surveys, which are the main source of data on alcohol exposure, suffer from bias and uncertainty. This article proposes a novel triangulation method to reduce bias by rescaling consumption estimates by sex and age to match country-level consumption from administrative data. Methods We used data from 17 population surveys to estimate age- and sex-specific trends in alcohol consumption in the adult population of South Africa between 1998 and 2016. Independently for each survey, we calculated sex- and age-specific estimates of the prevalence of drinkers and the distribution of individuals across consumption categories. We used these aggregated results, together with data on alcohol production, sales and import/export, as inputs of a Bayesian model and generated yearly estimates of the prevalence of drinkers in the population and the parameters that characterise the distribution of the average consumption among drinkers. Results Among males, the prevalence of drinkers decreased between 1998 and 2009, from 56.2% (95% CI 53.7%; 58.7%) to 50.6% (49.3%; 52.0%), and increased afterwards to 53.9% (51.5%; 56.2%) in 2016. The average consumption from 52.1 g/day (49.1; 55.6) in 1998 to 42.8 g/day (40.0; 45.7) in 2016. Among females the prevalence of current drinkers rose from 19.0% (17.2%; 20.8%) in 1998 to 20.0% (18.3%; 21.7%) in 2016 while average consumption decreased from 32.7 g/day (30.2; 35.0) to 26.4 g/day (23.8; 28.9). Conclusions The methodology provides a viable alternative to current approaches to reconcile survey estimates of individual alcohol consumption patterns with aggregate administrative data. It provides sex- and age-specific estimates of prevalence of drinkers and distribution of average daily consumption among drinkers in populations. Reliance on locally sourced data instead of global and regional trend estimates better reflects local nuances and is adaptable to the inclusion of additional data. This provides a powerful tool to monitor consumption, develop burden of disease estimates and inform and evaluate public health interventions

Prevalence of type 2 diabetes in South Africa : a systematic review and meta-analysis

Synthesis of existing prevalence data using rigorous systematic review methods is considered an effective strategy to generate representative and robust prevalence figures to inform health planning and policy. The purpose of this systematic review was to identify, collate, and synthesise all studies reporting the prevalence of total and newly diagnosed type 2 diabetes (T2DM), impaired glucose tolerance (IGT), and impaired fasting glucose (IFG) in South Africa. Four databases, PubMed, Scopus,Web of Science, and African Index Medicus were searched for articles published between January 1997 and June 2020. A total of 1886 articles were identified, of which 11 were included in the meta-analysis. The pooled prevalence in individuals 25 years and older was 15.25% (11.07–19.95%) for T2DM, 9.59% (5.82–14.17%) for IGT, 3.55% (0.38–9.61%) for IFG, and 8.29% (4.97–12.34%) for newly diagnosed T2DM. Although our pooled estimate may be imprecise due to significant heterogeneity across studies with regard to population group, age, gender, setting, diagnostic test, and study design, we provide evidence that the burden of glucose intolerance in South Africa is high. These factors contribute to the paucity of representative T2DM prevalence data. There is a need for well-designed epidemiological studies that use best-practice and standardised methods to assess prevalence.SUPPLEMENTARY MATERIAL : Table S1: PRISMA 2009 Checklist. Table S2: PubMed search strategy. Table S3: Quality assessment criteria for prevalence studies. Table S4: Prevalence of T2DM in South Africans aged 25 years and older. Table S5: Prevalence of IGT, IFG and undiagnosed T2DM in South Africans aged 25 years and older. Table S6: Level of evidence as qualified with GRADE. Figure S1: Funnel plot of included studies.The South African Medical Research Councilhttps://www.mdpi.com/journal/ijerpham2022Obstetrics and Gynaecolog

Persistent burden from non-communicable diseases in South Africa needs strong action

Continued effort and politcal will must be directed towards preventing, delaying the onset of and managing non-communicable diseases in South Africa

Emerging trends in non-communicable disease mortality in South Africa, 1997 - 2010

Objectives. National trends in age-standardised death rates (ASDRs) for non-communicable diseases (NCDs) in South Africa (SA) were identified between 1997 and 2010.Methods. As part of the second National Burden of Disease Study, vital registration data were used after validity checks, proportional redistribution of missing age, sex and population group, demographic adjustments for registration incompleteness, and identification of misclassified AIDS deaths. Garbage codes were redistributed proportionally to specified codes by age, sex and population group. ASDRs were calculated using mid-year population estimates and the World Health Organization world standard.Results. Of 594 071 deaths in 2010, 38.9% were due to NCDs (42.6% females). ASDRs were 287/100 000 for cardiovascular diseases (CVDs), 114/100 000 for cancers (malignant neoplasms), 58/100 000 for chronic respiratory conditions and 52/100 000 for diabetes mellitus. An overall annual decrease of 0.4% was observed resulting from declines in stroke, ischaemic heart disease, oesophageal and lung cancer, asthma and chronic respiratory disease, while increases were observed for diabetes, renal disease, endocrine and nutritional disorders, and breast and prostate cancers. Stroke was the leading NCD cause of death, accounting for 17.5% of total NCD deaths. Compared with those for whites, NCD mortality rates for other population groups were higher at 1.3 for black Africans, 1.4 for Indians and 1.4 for coloureds, but varied by condition.Conclusions. NCDs contribute to premature mortality in SA, threatening socioeconomic development. While NCD mortality rates have decreased slightly, it is necessary to strengthen prevention and healthcare provision and monitor emerging trends in cause-specific mortality to inform these strategies if the target of 2% annual decline is to be achieved

Mortality trends and diff erentials in South Africa from 1997 to 2012: second National Burden of Disease Study

Background The poor health of South Africans is known to be associated with a quadruple disease burden. In the second National Burden of Disease (NBD) study, we aimed to analyse cause of death data for 1997–2012 and develop national, population group, and provincial estimates of the levels and causes of mortality. Method We used underlying cause of death data from death notifi cations for 1997–2012 obtained from Statistics South Africa. These data were adjusted for completeness using indirect demographic techniques for adults and comparison with survey and census estimates for child mortality. A regression approach was used to estimate misclassifi ed HIV/AIDS deaths and so-called garbage codes were proportionally redistributed by age, sex, and population group population group (black African, Indian or Asian descent, white [European descent], and coloured [of mixed ancestry according to the preceding categories]). Injury deaths were estimated from additional data sources. Age-standardised death rates were calculated with mid-year population estimates and the WHO age standard. Institute of Health Metrics and Evaluation Global Burden of Disease (IHME GBD) estimates for South Africa were obtained from the IHME GHDx website for comparison. Findings All-cause age-standardised death rates increased rapidly since 1997, peaked in 2006 and then declined, driven by changes in HIV/AIDS. Mortality from tuberculosis, non-communicable diseases, and injuries decreased slightly. In 2012, HIV/AIDS caused the most deaths (29·1%) followed by cerebrovascular disease (7·5%) and lower respiratory infections (4·9%). All-cause age-standardised death rates were 1·7 times higher in the province with the highest death rate compared to the province with the lowest death rate, 2·2 times higher in black Africans compared to whites, and 1·4 times higher in males compared with females. Comparison with the IHME GBD estimates for South Africa revealed substantial diff erences for estimated deaths from all causes, particularly HIV/AIDS and interpersonal violence. Interpretation This study shows the reversal of HIV/AIDS, non-communicable disease, and injury mortality trends in South Africa during the study period. Mortality diff erentials show the importance of social determinants, raise concerns about the quality of health services, and provide relevant information to policy makers for addressing inequalities. Diff erences between GBD estimates for South Africa and this study emphasise the need for more careful calibration of global models with local data

Validation of the Thomson, Perry and Miller (2007) Collaboration Instrument in the South African context

Orientation: Collaboration is deemed important in today’s connected and complex business environment. People’s ability to collaborate with each other in organisations is becoming a business imperative. This study focuses on a valid measurement of collaboration within organisations. Research purpose: Thomson, Perry and Miller (2007) developed a collaboration measurement instrument in the United States. The aim of this study was to validate this instrument for a South African context. Motivation for the study: South African organisations face unique challenges that require optimal use of resources to improve business results. Effective collaboration is considered a powerful strategy to achieve this. Measuring the extent of collaboration can help to identify required changes in business practices. As far as could be established, there is no evidence of collaboration instruments developed and validated in South Africa. Research design, approach and method: Additional items were designed for further development of the Thomson, Perry and Miller (2007) Collaboration Instrument sub-scales, as suggested by the authors. The revised questionnaire consisting of 31 (17 existing, 14 new) items was distributed electronically to 4200 employees in two organisations, with 343 valid responses received. Reliability and construct validity were tested, as was convergent validity of the norms factor with the Trust in Teams Scale. Main findings: The results of the study support a four-factor, 29-item model of collaboration when applied to a South African sample. Cronbach’s alpha ranged between 0.85 and 0.95. Confirmatory Factor Analysis fits were at an acceptable level. Convergent validity showed a moderate fit with the data. Practical/managerial implications: South African managers and human resources practitioners can utilise results to foster a collaborative environment. Contribution/value-add: This study builds on the theoretical concept of collaboration as defined by Thomson, Perry and Miller (2007)