The age patterns of severe malaria syndromes in sub-Saharan Africa across a range of transmission intensities and seasonality settings.

BACKGROUND: A greater understanding of the relationship between transmission intensity, seasonality and the age-pattern of malaria is needed to guide appropriate targeting of malaria interventions in different epidemiological settings. METHODS: A systematic literature review identified studies which reported the age of paediatric hospital admissions with cerebral malaria (CM), severe malarial anaemia (SMA), or respiratory distress (RD). Study sites were categorized into a 3 × 2 matrix of Plasmodium falciparum transmission intensity and seasonality. Probability distributions were fitted by maximum likelihood methods, and best fitting models were used to estimate median ages and to represent graphically the age-pattern of each outcome for each transmission category in the matrix. RESULTS: A shift in the burden of CM towards younger age groups was seen with increasing intensity of transmission, but this was not the case for SMA or RD. Sites with 'no marked seasonality' showed more evidence of skewed age-patterns compared to areas of 'marked seasonality' for all three severe malaria syndromes. CONCLUSIONS: Although the peak age of CM will increase as transmission intensity decreases in Africa, more than 75% of all paediatric hospital admissions of severe malaria are likely to remain in under five year olds in most epidemiological settings.

Monitoring childbirth care in primary health facilities: a validity study in Gombe State, northeastern Nigeria.

BACKGROUND: Improving the quality of facility-based births is a critical strategy for reducing the high burden of maternal and neonatal mortality and morbidity across all settings. Accurate data on childbirth care is essential for monitoring progress. In northeastern Nigeria, we assessed the validity of childbirth care indicators in a rural primary health care context, as documented by health workers and reported by women at different recall periods. METHODS: We compared birth observations (gold standard) to: (i) facility exit interviews with observed women; (ii) household follow-up interviews 9-22 months after childbirth; and (iii) health worker documentation in the maternity register. We calculated sensitivity, specificity, and area under the receiver operating curve (AUC) to determine individual-level reporting accuracy. We calculated the inflation factor (IF) to determine population-level validity. RESULTS: Twenty-five childbirth care indicators were assessed to validate health worker documentation and women's self-reports. During exit interviews, women's recall had high validity (AUC≥0.70 and 0.75

The burden of malaria mortality among African children in the year 2000.

BACKGROUND: Although malaria is a leading cause of child deaths, few well-documented estimates of its direct and indirect burden exist. Our objective was to estimate the number of deaths directly attributable to malaria among children <5 years old in sub-Saharan Africa for the year 2000. METHODS: We divided the population into six sub-populations and, using results of studies identified in a literature review, estimated a malaria mortality rate for each sub-population. Malaria deaths were estimated by multiplying each sub-population by its corresponding rate. Sensitivity analyses were performed to assess the impact of varying key assumptions. RESULTS: The literature review identified 31 studies from 14 countries in middle Africa and 17 studies and reports from four countries in southern Africa. In 2000, we estimated that approximately 100 million children lived in areas where malaria transmission occurs and that 803 620 (precision estimate: 705 821-901 418) children died from the direct effects of malaria. For all of sub-Saharan Africa, including populations not exposed to malaria, malaria accounted for 18.0% (precision estimate: 15.8-20.2%) of child deaths. These estimates were sensitive to extreme assumptions about the causes of deaths with no known cause. CONCLUSIONS: These estimates, based on the best available data and methods, clearly demonstrate malaria's enormous mortality burden. We emphasize that these estimates are an approximation with many limitations and that the estimates do not account for malaria's large indirect burden. We describe information needs that, if filled, might improve the validity of future estimates.

Measuring implementation strength: lessons from the evaluation of public health strategies in low- and middle-income settings.

Evaluation of strategies to ensure evidence-based, low-cost interventions reach those in need is critical. One approach is to measure the strength, or intensity, with which packages of interventions are delivered, in order to explore the association between implementation strength and public health gains. A recent systematic review suggested methodological guidance was needed. We described the approaches used in three examples of measures of implementation strength in evaluation. These addressed important public health topics with a substantial disease burden in low-and middle-income countries; they involved large-scale implementation; and featured evaluation designs without comparison areas. Strengths and weaknesses of the approaches were discussed. In the evaluation of Ethiopia's Health Extension Programme, implementation strength scoring for each kebele (ward) was based on aggregated data from interviews with mothers of children aged 12-23 months, reflecting their reports of contact with four elements of the programme. An evaluation of the Avahan HIV prevention programme in India used the cumulative amount of Avahan funding per HIV-infected person spent each year in each district. In these cases, a single measure was developed and the association with hypothesised programme outcomes presented. In the evaluation of the Affordable Medicines Facility-malaria, several implementation strength measures were developed based on the duration of activity of the programme and the level of implementation of supporting interventions. Measuring the strength of programme implementation and assessing its association with outcomes is a promising approach to strengthen pragmatic impact evaluation. Five key aspects of developing an implementation strength measure are to: (a) develop a logic model; (b) identify aspects of implementation to be assessed; (c) design and implement data collection from a range of data sources; (d) decide whether and how to combine data into a single measure; and, (e) plan whether and how to use the measure(s) in outcome analysis.

Which delivery systems reach the poor? A review of equity of coverage of ever-treated nets, never-treated nets, and immunisation to reduce child mortality in Africa.

Insecticide-treated nets (ITNs) and childhood vaccination are two of the most powerful interventions available to prevent childhood mortality in Africa, but ITN coverage is still very low. Current debates about how to increase ITN coverage are concerned with the roles of different supply and delivery systems, in particular whether or not commercial net markets have any useful role. Here, we review data available on coverage and equity of coverage of three interventions to prevent childhood mortality. We compiled and analysed data from nationally representative surveys in 26 African countries to compare equity of coverage of (1) the Expanded Programme on Immunisation (EPI), (2) any net, (3) ever-treated nets (ie, ITNs), and (4) never-treated nets (ie, untreated nets; UTNs). We assumed that ever-treated net coverage mostly reflects the activities of public-health programmes and projects, and that never-treated net coverage mostly reflects the activity of local unsubsidised commercial markets. We discuss the validity, limitations, and possible biases of these assumptions. We estimate that 87% of the 8.4 million children protected by nets used UTNs. We used the concentration index (CI) to assess equity of coverage of the interventions. The data shows that never-treated net coverage is surprisingly equitable: overall, and despite substantial regional variations, it is comparable in equity to EPI (median CI(UTN)=0.166, CI(EPI)=0.075; p=0.3). In almost all countries, coverage of ITNs is strongly concentrated in the least poor households, and significantly more inequitable than both UTNs (median CI(ITN)=0.435, mean CI(UTN)=0.158; p<0.001) and EPI (median CI(ITN)=0.435, CI(EPI)=0.075; p<0.001). These results suggest that the public-health value of commercial net markets has been greatly underestimated, and that these markets have so far contributed more to equitable and sustainable coverage of mosquito nets, and hence to the prevention of malaria in Africa, than have the ITNs delivered by public-health systems and projects.