Estimating the burden of disease attributable to four selected environmental risk factors in South Africa

Validation of the Bayley Infant Neurodevelopmental Screener Among HIV-Exposed Infants in Rural South Africa

INTRODUCTION

Screening for developmental delays during critical periods of infant development is essential for early detection and intervention. Among high-risk infants in resource-limited settings, including those who are HIV exposed, there is a greater need for screening. This study expanded on previous analyses of the Bayley Infant Neurodevelopmental Screener (BINS) by providing psychometric properties to evaluate the appropriateness of using the BINS in a sample of HIV-exposed infants in rural South Africa.

METHOD

A total of 160 mothers with HIV, their infants, and their male partners were recruited. The BINS was administered to the infants, and their weights were recorded. Mothers completed measures of depression, intimate partner violence, male involvement, and adherence. Male partners reported their own involvement in perinatal care.

RESULTS

Results demonstrated support for a 5-factor structure consistent with previous transcultural adaptations of the BINS, demonstrating construct validity, and adequate reliability. Convergent validity was partially supported, as shown by associations with intimate partner violence and male involvement as reported by men and women and maternal adherence, although not with birth weight or maternal depression. The BINS showed adequate discriminating power, with only a few low-performing items.

CONCLUSION

In rural South Africa, a resource-limited setting, the BINS seems to be an adequate screening tool for developmental delays in children that may be used to identify those in need of intervention. Considering the high prevalence of delays identified in this study, antiretroviral therapy-exposed and HIV-exposed infants may benefit from further assessment to determine a need for intervention in community-based clinics.

Public health benefits of reducing exposure to ambient fine particulate matter in South Africa

Air pollution is a growing problem in developing countries, and there exists a wide range of evidence documenting the large health and productivity losses associated with high concentrations of pollutants. South Africa is a developing country with high levels of air pollution in some regions, and the costs of air pollution on human health and economic growth in South Africa are still uncertain. The environmental Benefits Mapping and Analysis Program (BenMAP) model was applied to South Africa using local data on population, mortality rates, and concentrations of fine particulate matter (PM_2.5), as well as mortality risk coefficients from the epidemiological literature. BenMAP estimates the number of premature deaths that would likely have been avoided if South African air quality levels met the existing annual National Ambient Air Quality Standard (NAAQS) of 20 μg m^-3, and the more stringent World Health Organization (WHO) guideline for annual average PM_2.5 of 10 μg m^-3. We estimate 14,000 avoided premature mortalities in 2012 if all of South Africa met the existing NAAQS annual average standard for PM_2.5. These avoided cases of mortality have an estimated monetary value of $14.0 billion (US2011$), which is equivalent to 2.2% of South Africa's 2012 GDP (PPP, US2011$). We estimate 28,000 avoided premature mortalities if the more stringent WHO guideline for annual average PM_2.5 is met across South Africa, which when expressed as a national burden is equivalent to 6% of all deaths in South Africa being attributable to PM_2.5 exposure. These avoided cases of mortality have an estimated monetary value of $29.1 billion, which is equivalent to 4.5% of South Africa's 2012 GDP. These results show that there are significant public health benefits to lowering PM_2.5 concentrations across South Africa, with correspondingly high economic benefits.

21st century research in urban WASH and health in sub-Saharan Africa: methods and outcomes in transition

Tackling global inequalities in access to Water, Sanitation and Hygiene (WASH) remains an urgent issue - 58% of annual diarrhoeal deaths are caused by inadequate WASH provision. A global context of increasing urbanisation, changing demographics and health transitions demands an understanding and impact of WASH on a broad set of health outcomes. We examine the literature, in terms of health outcomes, considering WASH access and interventions in urban sub-Saharan Africa from 2000 to 2017. Our review of studies which evaluate the effectiveness of specific WASH interventions, reveals an emphasis of WASH research on acute communicable diseases, particularly diarrhoeal diseases. In contrast, chronic communicable and non-communicable health outcomes were notable gaps in the literature as well as a lack of focus on cross-cutting issues, such as ageing, well-being and gender equality. We recommend a broader focus of WASH research and interventions in urban Africa to better reflect the demographic and health transitions happening. Abbreviations: CBA: Controlled Before and After; GSD: Government Service Delivery; IWDSSD: International Drinking-Water, Supply and Sanitation Decade (IDWSSD); KAP: Knowledge, Attitudes and Practices; IBD: Irritable Bowel Diseases; MDG: Millennium Development Goals; NTD: Neglected Tropical Diseases; PSSD: Private Sector Service Delivery; SDG: Sustainable Development Goals; SSA: Sub Saharan Africa; SODIS: Solar Disinfection System; STH: Soil Transmitted Helminths; RCT: Randomised Control Trial; WASH: Water Sanitation and Hygiene; WHO: World Health Organization.

Epidemiology of incident chlamydia and gonorrhoea infections and population attributable fractions associated with living in the inner-core of Winnipeg, Canada

Population attributable fractions help to convey public health significance of differential disease risk for chlamydia and gonorrhoea. Geographical residence serves as a useful proxy for complex processes creating ill health. Using population-based data, Poisson regression models were used to examine factors associated with chlamydia and gonorrhoea incidence. Population attributable fractions due to residency in the Winnipeg Health Region's inner-core were determined for chlamydia/gonorrhoea infections among 15-59-year olds (2005-2013), stratified by age group. For both chlamydia and gonorrhoea, it was found that the 15-24-year old age group had the highest incidence rates. There was also a stronger association between residency in the inner-core and incidence for gonorrhoea, compared to chlamydia. Overall, 24% (95% CI: 12-34%) of chlamydia infections were attributable to residency in the inner-core, compared to 46% (95% CI: 35-54%) for gonorrhoea ( p < .05). Within chlamydia/gonorrhoea, no statistically significant differences in population attributable fraction were observed by age group. The conclusion was that a concentration of efforts towards inner-core residents with gonorrhoea infections may result in a relatively larger decrease in incidence.

The geographic and demographic scope of shared sanitation: an analysis of national survey data from low- and middle-income countries

OBJECTIVE

A large and growing proportion of the world's population rely on shared sanitation facilities that have historically been excluded from international targets due to concerns about acceptability, hygiene and access. In connection with a proposed change in such policy, we undertook this study to describe the prevalence and scope of households that report relying on shared sanitation and to characterise them in terms of selected socio-economic and demographic covariates.

METHODS

We extracted data from the most recent national household surveys of 84 low- and middle-income countries from Demographic and Health Surveys and Multiple Indicator Cluster Surveys. We describe the prevalence of shared sanitation and explore associations between specified covariates and reliance on shared sanitation using log-binomial regression.

RESULTS

While household reliance on any type of shared sanitation is relatively rare in Europe (2.5%) and the Eastern Mediterranean (7.7%), it is not uncommon in the Americas (14.2%), Western Pacific (16.4%) and South-East Asia (31.3%), and it is most prevalent in Africa (44.6%) where many shared facilities do not meet the definition of 'improved' even if they were not shared (17.7%). Overall, shared sanitation is more common in urban (28.6%) than in rural settings (25.9%), even after adjusting for wealth. While results vary geographically, people who rely on shared sanitation tend to be poorer, reside in urban areas and live in households with more young children and headed by people with no formal education. Data from 21 countries suggest that most sharing is with neighbours and other acquaintances (82.0%) rather than the public.

CONCLUSIONS

The determinants of shared sanitation identified from these data suggest potential confounders that may explain the apparent increased health risk from sharing and should be considered in any policy recommendation. Both geographic and demographic heterogeneity indicate the need for further research to support a change in policies.

Analysis of a novel field dilution method for testing samples that exceed the analytic range of point-of-care blood lead analyzers

Investigators developed and evaluated a dilution method for the LeadCare II analyzer (LCII) for blood lead levels >65 μg/dL, the analyzer's maximum reporting value. Venous blood samples from lead-poisoned children were initially analyzed in the field using the dilution method. Split samples were analyzed at the US Centers for Disease Control and Prevention (CDC) laboratory using both the dilution method and inductively coupled plasma-mass spectrometry (ICP-MS). The concordance correlation coefficient of CDC LCII vs. ICP-MS values (N = 211) was 0.976 (95 % confidence interval (CI) 0.970-0.981); of Field LCII vs. ICP-MS (N = 68) was 0.910 (95% CI 0.861-0.942), and CDC LCII vs. Field LCII (N = 53) was 0.721 (95% CI 0.565-0.827). Sixty percent of CDC and 54% of Field LCII values were within ±10% of the ICP-MS value. Results from the dilution method approximated ICP-MS values and were useful for field-based decision-making. Specific recommendations for additional evaluation are provided.