Childhood mortality in sub-Saharan Africa : cross-sectional insight into small-scale geographical inequalities from Census data

Objectives To estimate and quantify childhood mortality, its spatial correlates and the impact of potential correlates using recent census data from three sub-Saharan African countries (Rwanda, Senegal and Uganda), where evidence is lacking. Design Cross-sectional. Setting Nation-wide census samples from three African countries participating in the 2010 African Census round. All three countries have conducted recent censuses and have information on mortality of children under 5 years. Participants 111 288 children under the age of 5 years in three countries. Primary and secondary outcome measures Under-five mortality was assessed alongside potential correlates including geographical location (where children live), and environmental, bio-demographic and socioeconomic variables. Results Multivariate analysis indicates that in all three countries the overall risk of child death in the first 5 years of life has decreased in recent years (Rwanda: HR=0.04, 95% CI 0.02 to 0.09; Senegal: HR=0.02 (95% CI 0.02 to 0.05); Uganda: HR=0.011 (95% CI 0.006 to 0.018). In Rwanda, lower deaths were associated with living in urban areas (0.79, 0.73, 0.83), children with living mother (HR=0.16, 95% CI 0.15 to 0.17) or living father (HR=0.38, 95% CI 0.36 to 0.39). Higher death was associated with male children (HR=1.06, 95% CI 1.02 to 1.08) and Christian children (HR=1.14, 95% CI 1.05 to 1.27). Children less than 1 year were associated with higher risk of death compared to older children in the three countries. Also, there were significant spatial variations showing inequalities in children mortality by geographic location. In Uganda, for example, areas of high risk are in the south-west and north-west and Kampala district showed a significantly reduced risk. Conclusions We provide clear evidence of considerable geographical variation of under-five mortality which is unexplained by factors considered in the data. The resulting under-five mortality maps can be used as a practical tool for monitoring progress within countries for the Millennium Development Goal 4 to reduce under-five mortality in half by 2015

No. 26: The Supermarket Revolution and Food Security in Namibia

The surprisingly high rate of supermarket patronage in low-income areas of Windhoek, Namibia’s capital and largest city, is at odds with conventional wisdom that supermarkets in African cities are primarily patronized by middle and high-income residents and therefore target their neighbourhoods. What is happening in Namibia and other Southern African countries that make supermarkets so much more accessible to the urban poor? What are they buying at supermarkets and how frequently do they shop there? Further, what is the impact of supermarket expansion on informal food vendors? This report, which presents the findings from the South African Supermarkets in Growing African Cities project research in 2016-2017 in Windhoek, looks at the evidence and tries to answer these questions and others. The research and policy debate on the relationship between the supermarket revolution and food security is also discussed. Here, the issues include whether supermarket supply chains and procurement practices mitigate rural food insecurity through providing new market opportunities for smallholder farmers; the impact of supermarkets on the food security and consumption patterns of residents of African cities; and the relationship between supermarket expansion and governance of the food system, particularly at the local level

No. 08: The Urban Food System of Windhoek, Namibia

The surprisingly high rate of supermarket patronage in low-income areas of Windhoek, Namibia’s capital and largest city, is at odds with conventional wisdom that supermarkets in African cities are primarily patronized by middle and high-income residents and therefore target their neighbourhoods. What is happening in Namibia and other Southern African countries that make supermarkets so much more accessible to the urban poor? What are they buying at supermarkets and how frequently do they shop there? Further, what is the impact of supermarket expansion on informal food vendors? This report, which presents the findings of the South African Supermarkets in Growing African Cities project research in 2016-2017 in Windhoek, looks at the evidence and tries to answer these questions and others. The research and policy debate on the relationship between the supermarket revolution and food security is also discussed. Here, the issues include whether supermarket supply chains and procurement practices mitigate rural food insecurity through providing new market opportunities for smallholder farmers; the impact of supermarkets on the food security and consumption patterns of residents of African cities; and the relationship between supermarket expansion and governance of the food system, particularly at the local level

Using structured additive regression models to estimate risk factors of malaria: analysis of 2010 Malawi malaria indicator survey data.

BACKGROUND: After years of implementing Roll Back Malaria (RBM) interventions, the changing landscape of malaria in terms of risk factors and spatial pattern has not been fully investigated. This paper uses the 2010 malaria indicator survey data to investigate if known malaria risk factors remain relevant after many years of interventions. METHODS: We adopted a structured additive logistic regression model that allowed for spatial correlation, to more realistically estimate malaria risk factors. Our model included child and household level covariates, as well as climatic and environmental factors. Continuous variables were modelled by assuming second order random walk priors, while spatial correlation was specified as a Markov random field prior, with fixed effects assigned diffuse priors. Inference was fully Bayesian resulting in an under five malaria risk map for Malawi. RESULTS: Malaria risk increased with increasing age of the child. With respect to socio-economic factors, the greater the household wealth, the lower the malaria prevalence. A general decline in malaria risk was observed as altitude increased. Minimum temperatures and average total rainfall in the three months preceding the survey did not show a strong association with disease risk. CONCLUSIONS: The structured additive regression model offered a flexible extension to standard regression models by enabling simultaneous modelling of possible nonlinear effects of continuous covariates, spatial correlation and heterogeneity, while estimating usual fixed effects of categorical and continuous observed variables. Our results confirmed that malaria epidemiology is a complex interaction of biotic and abiotic factors, both at the individual, household and community level and that risk factors are still relevant many years after extensive implementation of RBM activities

Quantifying Spatial Disparities in Neonatal Mortality Using a Structured Additive Regression Model

Background: Neonatal mortality contributes a large proportion towards early childhood mortality in developing countries, with considerable geographical variation at small areas within countries. Methods: A geo-additive logistic regression model is proposed for quantifying small-scale geographical variation in neonatal mortality, and to estimate risk factors of neonatal mortality. Random effects are introduced to capture spatial correlation and heterogeneity. The spatial correlation can be modelled using the Markov random fields (MRF) when data is aggregated, while the two dimensional P-splines apply when exact locations are available, whereas the unstructured spatial effects are assigned an independent Gaussian prior. Socio-economic and bio-demographic factors which may affect the risk of neonatal mortality are simultaneously estimated as fixed effects and as nonlinear effects for continuous covariates. The smooth effects of continuous covariates are modelled by second-order random walk priors. Modelling and inference use the empirical Bayesian approach via penalized likelihood technique. The methodology is applied to analyse the likelihood of neonatal deaths, using data from the 2000 Malawi demographic and health survey. The spatial effects are quantified through MRF and two dimensional P-splines priors. Results: Findings indicate that both fixed and spatial effects are associated with neonatal mortality. Conclusions: Our study, therefore, suggests that the challenge to reduce neonatal mortality goes beyond addressin

No. 23: Inclusive Growth and the Informal Food Sector in Windhoek, Nambia

This report presents the results of the first comprehensive survey of Windhoek’s rapidly-growing informal food sector. As such, it aims to shed light on the food system of Windhoek, Namibia’s capital and largest urban centre. The report is part of a research programme on food security in cities of the Global South by AFSUN and the Hungry Cities Partnership (HCP) and builds on earlier publications on Windhoek’s food system including: - The State of Food Insecurity in Windhoek, Namibia (Pendleton et al 2012); - The Supermarket Revolution and Food Security in Namibia (Nickanor et al 2017); - Urban Informal Food Deserts in Windhoek, Namibia (Nickanor et al 2018); - Supermarkets and Informal Food Vendors in Windhoek, Namibia (Nickanor et al 2019); and - Containing the Informal Food Sector in Windhoek, Namibia (Kazembe et al 2019). To date, most studies of the informal food sector in Namibia have relied on national surveys, in-depth interviews with a small sample of food vendors or indirect information on patronage of the informal food sector in household food security surveys. The latest HCP household survey showed that the informal food sector had expanded dramatically over the last decade and that around two-thirds of Windhoek households obtained some of their food from informal vendors (Nickanor et al 2017). Rates and frequency of food sourcing from the informal sector were especially high in the city’s large informal settlements (Nickanor et al 2019). For example, nearly 60% of surveyed households in informal settlements regularly patronize informal vendors operating in the city’s open markets. Just over one-quarter buy food from informal street vendors and 14% from informal tuck shops (sometimes called spazas) (Nickanor et al 2019). However, this is the first representative in-depth survey of food vendors themselves. A total of 470 vendors were interviewed for the study by researchers from the Department of Population and Statistics at the University of Namibia using the common HCP informal vendor survey instrument

Prevalence and associated factors of physical fighting among school-going adolescents in Namibia

<p>Abstract</p> <p>Background</p> <p>Interpersonal physical violence is an important global public health concern that has received limited attention in the developing world. There is in particular a paucity of data regarding physical violence and its socio-demographic correlates among in-school adolescents in Namibia.</p> <p>Methods</p> <p>We analysed cross-sectional data from the Namibia Global School-Based Health Survey (GSHS) conducted in 2004. We aimed to estimate the prevalence and socio-demographic correlates of physical fighting within the last 12 months. We obtained frequencies of socio-demographic attributes. We also assessed the association between self-reported history of having engaging in a physical fight and a selected list of independent variables using logistic regression analysis.</p> <p>Results</p> <p>Of the 6283 respondents, 50.6% (55.2% males and 46.2% females) reported having been in a physical fight in the past 12 months. Males were more likely to have been in a physical fight than females (OR = 1.71, 95% CI (1.44, 2.05)). Smoking, drinking alcohol, using drugs and bullying victimization were positively associated with fighting (OR = 1.91, 95% CI (1.49, 2.45); OR = 1.48, 95% CI (1.21, 1.81); OR = 1.55, 95% CI (1.22, 1.81); and OR = 3.12, 95% CI (2.62, 3.72), respectively). Parental supervision was negatively associated with physical fighting (OR = 0.82, 95% CI (0.69, 0.98)). Both male and female substance users (cigarette smoking, alcohol and drug use) were more likely to engage in physical fighting than non-substance users (OR = 3.53, 95% CI (2.60, 4.81) for males and OR = 11.01, 95% CI (7.25, 16.73) for females). Parental supervision was negatively associated with physical fighting (OR = 0.85, 95% CI (0.72, 0.99)).</p> <p>Conclusion</p> <p>Prevalence of physical fighting within the last 12 months was comparable to estimates obtained in European countries. We also found clustering of problem behaviours or experiences among adolescents who reported having engaged in physical violence in the past 12 months. There is a need to bring adolescent violent behaviour to the fore of the public health agenda in Namibia.</p

Care-seeking for diarrhoea in Southern Malawi : attitudes, practices and implications for diarrhoea control

This paper examined care-seeking behaviour and its associated risk factors when a family member had diarrhoea. Data was obtained from a survey conducted in Chikwawa, a district in Southern Malawi. Chikwawa is faced with a number of environmental and socioeconomic problems and currently diarrhoea morbidity in the district is estimated at 24.4% statistically higher than the national average at 17%. Using hierarchically built data from a survey of 1,403 households nested within 33 communities, a series of two level binary logistic regression models with Bayesian estimation were used to determine predictors of care-seeking behaviour. The results show that 68% of mothers used oral rehydration solutions (ORS) last time a child in their family had diarrhoea . However, when asked on the action they take when a member of their household has diarrhoea two thirds of the mothers said they visit a health facility. Most respondents (73%) mentioned distance and transport costs as the main obstacles to accessing their nearest health facility and the same proportion of respondents mentioned prolonged waiting time and absence of health workers as the main obstacles encountered at the health facilities. The main predictor variables when a member of the family had diarrhoea were maternal age, distance to the nearest health facility, school level, and relative wealth, household diarrhoea endemicity, and household size while the main predictor variables when a child had diarrhoea were existence of a village health committee (VHC), distance to the nearest health facility, and maternal age . Most households use ORS for the treatment of diarrhoea and village health committees and health surveillance assistants (HSAs) are important factors in this choice of treatment. Health education messages on the use and efficacy of ORS to ensure proper and prescribed handling are important. There is need for a comprehensive concept addressing several dimensions of management and proper coordination of delivery of resources and services; availability of adequate healthcare workers at all levels; affordability to accessibility of healthcare resources and services to all communities; acceptability and quality of care; intensification of health education messages on the use and management of ORS, and prompt and timely treatment of diarrhoeal illness

Modelling the effect of malaria endemicity on spatial variations in childhood fever, diarrhoea and pneumonia in Malawi

BACKGROUND: Co-morbidity with conditions such as fever, diarrhoea and pneumonia is a common phenomenon in tropical Africa. However, little is known about geographical overlaps in these illnesses. Spatial modelling may improve our understanding of the epidemiology of the diseases for efficient and cost-effective control. METHODS: This study assessed subdistrict-specific spatial associations of the three conditions (fever, diarrhoea and pneumonia) in relation to malaria endemicity. We used data from the 2000 Malawi demographic and health survey which captured the history of childhood morbidities 2 weeks prior to the survey date. The disease status of each child in each area was the outcome of interest and was modelled using a trivariate logistic regression model, and incorporated random effects to measure spatial correlation. RESULTS: The risk of fever was positively associated with high and medium malaria endemicity levels relative to low endemicity level, while for diarrhoea and pneumonia we observed marginal positive association at high endemicity level relative to low endemicity level, controlling for confounding covariates and heterogeneity. A positive spatial correlation was found between fever and diarrhoea (r = 0.29); while weak associations were estimated between fever and pneumonia (r = 0.01); and between diarrhoea and pneumonia (r = 0.05). The proportion of structured spatial variation compared to unstructured variation was 0.67 (95% credible interval (CI): 0.31-0.91) for fever, 0.67 (95 % CI: 0.27-0.93) for diarrhoea, and 0.87 (95% CI: 0.62-0.96) for pneumonia. CONCLUSION: The analysis suggests some similarities in subdistrict-specific spatial variation of childhood morbidities of fever, diarrhoea and pneumonia, and might be a result of shared and overlapping risk factors, one of which is malaria endemicity

The pattern of variation between diarrhoea and malaria coexistence with corresponding risk factors in, Chikhwawa, Malawi : a bivariate multilevel analysis

Developing countries face a huge burden of infectious diseases, a number of which co-exist. This paper estimates the pattern and variation of malaria and diarrhea coexistence in Chikhwawa, a district in Southern Malawi using bivariate multilevel modelling with Bayesian estimation. A probit link was employed to examine hierarchically built data from a survey of individuals (n = 6,727) nested within households (n = 1,380) nested within communities (n = 33). Results show significant malaria [σ2ul = 0.901 (95% CI : 0.746,1.056) ] and diarrhea [σ2ul = 1.009  (95% CI : 0.860,1.158) ] variations with a strong correlation between them [ru(1,2) = 0.565 ] at household level. There are significant malaria [σ2v1 = 0.053 (95% CI : 0.018,0.088) ] and diarrhea [σ2v2 = 0.099 (95% CI : 0.030,0.168 ] variations at community level but with a small correlation [rv(1,2) = 0.124 ] between them. There is also significant correlation between malaria and diarrhea at individual level [re(1,2) 0.241]. These results suggest a close association between reported malaria-like illness and diarrheal illness especially at household and individual levels in Southern Malawi