President's Malaria Research Articles

Effect of Supportive Supervision on Malaria Microscopy Competencies in Sub-Saharan Africa.

Although light microscopy is the reference standard for diagnosing malaria, maintaining skills over time can be challenging. Between 2015 and 2017, the U.S. President's Malaria Initiative-funded MalariaCare project supported outreach training and supportive supervision (OTSS) visits at 1,037 health facilities in seven African countries to improve performance in microscopy slide preparation, staining, and reading. During these visits, supervisors observed and provided feedback to health-care workers (HCWs) performing malaria microscopy using a 30-step checklist. Of the steps observed in facilities with at least three visits, the proportion of HCWs that performed each step correctly at baseline ranged from 63.2% to 94.2%. The change in the proportion of HCWs performing steps correctly by the third visit ranged from 16.7 to 23.6 percentage points (n = 916 observations). To assess the overall improvement, facility scores were calculated based on the steps performed correctly during each visit. The mean score at baseline was 85.7%, demonstrating a high level of performance before OTSS. Regression analysis predicted an improvement in facility scores of 3.6 percentage points (P < 0.001) after three visits across all countries. In reference-level facilities with consistently high performance on microscopy procedures and parasite detection, quality assurance (QA) mechanisms could prioritize more advanced skills, such as proficiency testing for parasite counting and species identification. However, in settings with high staff turnover and declining use of microscopy in favor of rapid diagnostic tests, additional supervision visits and/or additional QA measures may be required to improve and maintain performance.

Indoor Residual Spraying for Malaria Control in Sub-Saharan Africa 1997 to 2017: An Adjusted Retrospective Analysis

Background: Indoor residual spraying (IRS) is a key tool for controlling and eliminating malaria by targeting vectors. To support the development of effective intervention strategies it is important to understand the impact of vector control tools on malaria incidence and on the spread of insecticide resistance. In 2006, the World Health Organization (WHO) stated that countries should report on coverage and impact of IRS, yet IRS coverage data are still sparse and unspecific. Methods: Data on IRS deployment were collated from a variety of sources, including the President's Malaria Initiative spray reports and National Malaria Control program reports, for all 46 malaria-endemic countries in Sub-Saharan Africa from 1997 to 2017. The data were mapped to the applicable administrative divisions and the proportion of households sprayed for each of the four main insecticide classes; carbamates, organochlorines, organophosphates and pyrethroids was calculated. Findings: The number of countries implementing IRS has increased considerably although coverage in-country is often low, particularly in West Africa. From 1997 to 2010 there was an expansion of IRS using organochlorines (DDT) and pyrethroids. From 2011, carbamates partly replaced these insecticides and organophosphate use increased from 2013 onwards, however, policy recommendations to rotate between insecticide classes were rarely followed. Interpretation: Our results highlight trends in IRS coverage and insecticide choice in sub Saharan Africa. The data presented here can improve studies on the impact of IRS on malaria incidence and on insecticide resistance development and help to guide future malaria control efforts. Funding Statement: Wellcome Trust grant 108440/Z/15/Z. Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: Not Required.

The links between agriculture, Anopheles mosquitoes, and malaria risk in children younger than 5 years in the Democratic Republic of the Congo: a population-based, cross-sectional, spatial study

SummaryBackgroundThe relationship between agriculture, Anopheles mosquitoes, and malaria in Africa is not fully understood, but it is important for malaria control as countries consider expanding agricultural projects to address population growth and food demand. Therefore, we aimed to assess the effect of agriculture on Anopheles biting behaviour and malaria risk in children in rural areas of the Democratic Republic of the Congo (DR Congo).MethodsWe did a population-based, cross-sectional, spatial study of rural children (<5 years) in the DR Congo. We used information about the presence of malaria parasites in each child, as determined by PCR analysis of dried-blood spots from the 2013–14 DR Congo Demographic and Health Survey (DHS). We also used data from the DHS, a longitudinal entomological study, and available land cover and climate data to evaluate the relationships between agriculture, Anopheles biting behaviour, and malaria prevalence. Satellite imagery was used to measure the percentage of agricultural land cover around DHS villages and Anopheles sites. Anopheles biting behaviour was assessed by Human Landing Catch. We used probit regression to assess the relationship between agriculture and the probability of malaria infection, as well as the relationship between agriculture and the probability that a mosquito was caught biting indoors.FindingsBetween Aug 13, 2013, and Feb 13, 2014, a total of 9790 dried-blood spots were obtained from the DHS, of which 4612 participants were included in this study. Falciparum malaria infection prevalence in rural children was 38·7% (95% uncertainty interval [UI] 37·3–40·0). Increasing exposure to agriculture was associated with increasing malaria risk with a high posterior probability (estimate 0·07, 95% UI −0·04 to 0·17; posterior probability [estimate >0]=0·89), with the probability of malaria infection increased between 0·2% (95% UI −0·1 to 3·4) and 2·6% (–1·5 to 6·6) given a 15% increase in agricultural cover, depending on other risk factors. The models predicted that large increases in agricultural cover (from 0% to 75%) increase the probability of infection by as much as 13·1% (95% UI −7·3 to 28·9). Increased risk might be due to Anopheles gambiae sensu lato, whose probability of biting indoors increased between 11·3% (95% UI −15·3 to 25·6) and 19·7% (–12·1 to 35·9) with a 15% increase in agriculture.InterpretationMalaria control programmes must consider the possibility of increased risk due to expanding agriculture. Governments considering initiating large-scale agricultural projects should therefore also consider accompanying additional malaria control measures.FundingNational Institutes of Health, National Science Foundation, Bill & Melinda Gates Foundation, President's Malaria Initiative, and Royster Society of Fellows at the University of North Carolina at Chapel Hill.

Equal Opportunity, Equal Work: Increasing Women's Participation in the U.S. President's Malaria Initiative Africa Indoor Residual Spraying Project.

One of the primary control measures for malaria transmission is indoor residual spraying (IRS). Historically, few women have worked in IRS programs, despite the income-generating potential. Increasing women's roles in IRS requires understanding the barriers to women's participation and implementing measures to address them. The U.S. President's Malaria Initiative (PMI) Africa Indoor Residual Spraying (AIRS) Project is the largest implementer of IRS globally. To address gender inequity in IRS operations, PMI AIRS assessed the barriers to the participation of women and developed and implemented policies to address these barriers. The PMI AIRS Project initially identified barriers through a series of informal assessments with key stakeholders. PMI AIRS then implemented a series of gender-guided policies, starting in 2015, in Benin, Ethiopia, Ghana, Mali, Madagascar, Mozambique, Rwanda, Senegal, Zambia, and Zimbabwe. The policies included adapting physical work environments to ensure privacy for women; ensuring the safety of women in the workplace; guaranteeing safety and job security of women during pregnancy; and encouraging qualified women to apply for supervisory positions. The project collected routine programmatic data on staff, spray quality, and spray efficiency; data from 2012 through the end of 2015 were analyzed (up through 1 year after implementation of the gender policies). In addition, PMI AIRS conducted surveys in 2015, 2016, and 2017 before and after the spray campaigns in 4 countries to determine changes in gender norms among spray operators through questions about decision making and agency. The PMI AIRS Project increased women's employment with the program. Specifically, women's employment increased overall from 23% in 2012 to 29% in 2015, with a 2015 range from 16% (Mali) to 40% (Madagascar). Growth among supervisor roles was even stronger, with the percentage of women in supervisory roles increasing from 17% in 2012 to 46% in 2015, with a 2015 range from 9% (Mali) to 50% (Madagascar). While the data showed that in most countries women sprayed fewer houses per day than men in 2015, the differences were not meaningful, ranging from 0.1 to 1.2 households per day. Gender norms shifted toward more egalitarian views in 2 of the 4 countries with survey data. Preliminary results suggest the PMI AIRS Project gender policies are increasing the engagement of women in all aspects of spray operations, especially in supervisory roles. Expansion of these policies to all countries implementing IRS and to malaria control implementation more broadly is recommended.

Capacity Development through the US President's Malaria Initiative-Supported Antimalarial Resistance Monitoring in Africa Network.

Antimalarial drug resistance is an evolving global health security threat to malaria control. Early detection of Plasmodium falciparum resistance through therapeutic efficacy studies and associated genetic analyses may facilitate timely implementation of intervention strategies. The US President’s Malaria Initiative–supported Antimalarial Resistance Monitoring in Africa Network has assisted numerous laboratories in partner countries in acquiring the knowledge and capability to independently monitor for molecular markers of antimalarial drug resistance.

The US President's Malaria Initiative, Plasmodium falciparum transmission and mortality: A modelling study.

BackgroundAlthough significant progress has been made in reducing malaria transmission globally in recent years, a large number of people remain at risk and hence the gains made are fragile. Funding lags well behind amounts needed to protect all those at risk and ongoing contributions from major donors, such as the President’s Malaria Initiative (PMI), are vital to maintain progress and pursue further reductions in burden. We use a mathematical modelling approach to estimate the impact of PMI investments to date in reducing malaria burden and to explore the potential negative impact on malaria burden should a proposed 44% reduction in PMI funding occur.Methods and findingsWe combined an established mathematical model of Plasmodium falciparum transmission dynamics with epidemiological, intervention, and PMI-financing data to estimate the contribution PMI has made to malaria control via funding for long-lasting insecticide treated nets (LLINs), indoor residual spraying (IRS), and artemisinin combination therapies (ACTs). We estimate that PMI has prevented 185 million (95% CrI: 138 million, 230 million) malaria cases and saved 940,049 (95% CrI: 545,228, 1.4 million) lives since 2005. If funding is maintained, PMI-funded interventions are estimated to avert a further 162 million (95% CrI: 116 million, 194 million) cases, saving a further 692,589 (95% CrI: 392,694, 955,653) lives between 2017 and 2020. With an estimate of US$94 (95% CrI: US$51, US$166) per Disability Adjusted Life Year (DALY) averted, PMI-funded interventions are highly cost-effective. We also demonstrate the further impact of this investment by reducing caseloads on health systems. If a 44% reduction in PMI funding were to occur, we predict that this loss of direct aid could result in an additional 67 million (95% CrI: 49 million, 82 million) cases and 290,649 (95% CrI: 167,208, 395,263) deaths between 2017 and 2020. We have not modelled indirect impacts of PMI funding (such as health systems strengthening) in this analysis.ConclusionsOur model estimates that PMI has played a significant role in reducing malaria cases and deaths since its inception. Reductions in funding to PMI could lead to large increases in the number of malaria cases and deaths, damaging global goals of malaria control and elimination.

Using Rainfall and Temperature Data in the Evaluation of National Malaria Control Programs in Africa.

.Since 2010, the Roll Back Malaria (RBM) Partnership, including National Malaria Control Programs, donor agencies (e.g., President's Malaria Initiative and Global Fund), and other stakeholders have been evaluating the impact of scaling up malaria control interventions on all-cause under-five mortality in several countries in sub-Saharan Africa. The evaluation framework assesses whether the deployed interventions have had an impact on malaria morbidity and mortality and requires consideration of potential nonintervention influencers of transmission, such as drought/floods or higher temperatures. Herein, we assess the likely effect of climate on the assessment of the impact malaria interventions in 10 priority countries/regions in eastern, western, and southern Africa for the President's Malaria Initiative. We used newly available quality controlled Enhanced National Climate Services rainfall and temperature products as well as global climate products to investigate likely impacts of climate on malaria evaluations and test the assumption that changing the baseline period can significantly impact on the influence of climate in the assessment of interventions. Based on current baseline periods used in national malaria impact assessments, we identify three countries/regions where current evaluations may overestimate the impact of interventions (Tanzania, Zanzibar, Uganda) and three countries where current malaria evaluations may underestimate the impact of interventions (Mali, Senegal and Ethiopia). In four countries (Rwanda, Malawi, Mozambique, and Angola) there was no strong difference in climate suitability for malaria in the pre- and post-intervention period. In part, this may be due to data quality and analysis issues.

Implementing Impact Evaluations of Malaria Control Interventions: Process, Lessons Learned, and Recommendations.

.As funding for malaria control increased considerably over the past 10 years resulting in the expanded coverage of malaria control interventions, so did the need to measure the impact of these investments on malaria morbidity and mortality. Members of the Roll Back Malaria (RBM) Partnership undertook impact evaluations of malaria control programs at a time when there was little guidance in terms of the process for conducting an impact evaluation of a national-level malaria control program. The President’s Malaria Initiative (PMI), as a member of the RBM Partnership, has provided financial and technical support for impact evaluations in 13 countries to date. On the basis of these experiences, PMI and its partners have developed a streamlined process for conducting the evaluations with a set of lessons learned and recommendations. Chief among these are: to ensure country ownership and involvement in the evaluations; to engage stakeholders throughout the process; to coordinate evaluations among interested partners to avoid duplication of efforts; to tailor the evaluation to the particular country context; to develop a standard methodology for the evaluations and a streamlined process for completion within a reasonable time; and to develop tailored dissemination products on the evaluation for a broad range of stakeholders. These key lessons learned and resulting recommendations will guide future impact evaluations of malaria control programs and other health programs.

The US President's Malaria Initiative and under-5 child mortality in sub-Saharan Africa: A difference-in-differences analysis.

BackgroundDespite substantial financial contributions by the United States President’s Malaria Initiative (PMI) since 2006, no studies have carefully assessed how this program may have affected important population-level health outcomes. We utilized multiple publicly available data sources to evaluate the association between introduction of PMI and child mortality rates in sub-Saharan Africa (SSA).Methods and findingsWe used difference-in-differences analyses to compare trends in the primary outcome of under-5 mortality rates and secondary outcomes reflecting population coverage of malaria interventions in 19 PMI-recipient and 13 non-recipient countries between 1995 and 2014. The analyses controlled for presence and intensity of other large funding sources, individual and household characteristics, and country and year fixed effects.PMI program implementation was associated with a significant reduction in the annual risk of under-5 child mortality (adjusted risk ratio [RR] 0.84, 95% CI 0.74–0.96). Each dollar of per-capita PMI expenditures in a country, a measure of PMI intensity, was also associated with a reduction in child mortality (RR 0.86, 95% CI 0.78–0.93). We estimated that the under-5 mortality rate in PMI countries was reduced from 28.9 to 24.3 per 1,000 person-years. Population coverage of insecticide-treated nets increased by 8.34 percentage points (95% CI 0.86–15.83) and coverage of indoor residual spraying increased by 6.63 percentage points (95% CI 0.79–12.47) after PMI implementation. Per-capita PMI spending was also associated with a modest increase in artemisinin-based combination therapy coverage (3.56 percentage point increase, 95% CI −0.07–7.19), though this association was only marginally significant (p = 0.054). Our results were robust to several sensitivity analyses. Because our study design leaves open the possibility of unmeasured confounding, we cannot definitively interpret these results as causal.ConclusionsPMI may have significantly contributed to reducing the burden of malaria in SSA and reducing the number of child deaths in the region. Introduction of PMI was associated with increased coverage of malaria prevention technologies, which are important mechanisms through which child mortality can be reduced. To our knowledge, this study is the first to assess the association between PMI and all-cause child mortality in SSA with the use of appropriate comparison groups and adjustments for regional trends in child mortality.

Malaria control adds to the evidence for health aid effectiveness.

In this Perspective, Eran Bendavid discusses the broader political and health consequences of US foreign aid in light of the study by Aleksandra Jakubowski and colleagues of the President's Malaria Initiative in sub-Saharan Africa.

Population coverage of artemisinin-based combination treatment in children younger than 5 years with fever and Plasmodium falciparum infection in Africa, 2003-2015: a modelling study using data from national surveys.

SummaryBackgroundArtemisinin-based combination therapies (ACTs) are the most effective treatment for uncomplicated Plasmodium falciparum malaria infection. A commonly used indicator for monitoring and assessing progress in coverage of malaria treatment is the proportion of children younger than 5 years with reported fever in the previous 14 days who have received an ACT. We propose an improved indicator that incorporates parasite infection status (as assessed by a rapid diagnostic test [RDT]), which is available in recent household surveys. In this study we estimated the annual proportion of children younger than 5 years with fever and a positive RDT in Africa who received an ACT in 2003–15.MethodsOur modelling study used cross-sectional data on treatment for fever and RDT status for children younger than 5 years compiled from all nationally available representative household surveys (the Malaria Indicator Surveys, Demographic and Health Surveys, and Multiple Indicator Cluster Surveys) across sub-Saharan Africa between 2003 and 2015. Estimates for the proportion of children younger than 5 years with a fever within the previous 14 days and P falciparum infection assessed by RDT who received an ACT were incorporated in a generalised additive mixed model, including data on ACT distributions, to estimate coverage across all countries and time periods. We did random effects meta-analyses to examine individual, household, and community effects associated with ACT coverage.FindingsWe obtained data on 201 704 children younger than 5 years from 103 surveys (22 MIS, 61 DHS, and 20 MICS) across 33 countries. RDT results were available for 40 of these surveys including 40 261 (20%) children, and we predicted RDT status for the remaining 161 443 (80%) children. Our results showed that ACT coverage in children younger than 5 years with a fever and P falciparum infection increased across sub-Saharan Africa in 2003–15, but even in 2015, only 19.7% (95% CI 15.6–24.8) of children younger than 5 years with a fever and P falciparum infection received an ACT. In meta-analyses, children younger than 5 years were more likely to receive an ACT for fever and P falciparum infection if they lived in an urban area (vs rural area; odds ratio [OR] 1.18, 95% CI 1.06–1.31), had household wealth above the national median (vs wealth below the median; OR 1.26, 1.16–1.39), had a caregiver with any education (vs no education; OR 1.31, 1.22–1.41), had a household insecticide-treated net (ITN; vs no ITN; OR 1.21, 1.13–1.29), were older than 2 years (vs ≤2 years; OR 1.09, 1.01–1.17), or lived in an area with a higher mean P falciparum prevalence in children aged 2–10 years (OR 1.12, 1.02–1.23). In the subgroup of children for whom treatment was sought, those who sought treatment in the public sector were more likely to receive an ACT (vs the private sector; OR 3.18, 2.67–3.78).InterpretationDespite progress during the 2003–15 malaria programme, ACT treatment for children with malaria remains unacceptably low. More work is needed at the country level to understand how health-care access, service delivery, and ACT supply might be improved to ensure appropriate treatment for all children with malaria.FundingUS President's Malaria Initiative and Medicines for Malaria Venture.

Interventions for an Artemisinin‐based Malaria Medicine Supply Chain

Artemisinin combination therapy, the most effective malaria treatment today, is manufactured from an agriculturally derived starting material Artemisia annua. Artemisinin, the main ingredient in malaria medicines, is extracted from Artemisia leaves and used in the production of medicine for treating malaria. The artemisinin market has witnessed high volatility in the supply and price of artemisinin extract. A large fraction of malaria medicines for endemic countries in sub‐Saharan Africa is financed by the Global Fund to Fight AIDS, TB, and Malaria and the US President's Malaria Initiative. These agencies together with the World Health Organization, UNITAID, the United Kingdom Department for International Development and the Bill and Melinda Gates Foundation are exploring ways to increase the level of artemisinin production, reduce volatility of artemisinin prices, and improve overall access to malaria medicines for the population. We develop a model of the supply chain, calibrate the model using field data, and investigate the impact of various interventions. Our model shows that initiatives aimed at improving average yield, creating a support‐price for agricultural artemisinin, and a larger and carefully managed supply of semi‐synthetic artemisinin have the greatest potential for improving supply and reducing price volatility of artemisinin‐based malaria medicine.

Trends in US President's Malaria Initiative-funded indoor residual spray coverage and insecticide choice in sub-Saharan Africa (2008-2015): urgent need for affordable, long-lasting insecticides.

This article reports the changing pattern of US President’s Malaria Initiative-funded IRS in sub-Saharan Africa between 2008 and 2015. IRS coverage in sub-Saharan Africa increased from <2 % of the at-risk population in 2005, to 11 % or 78 million people in 2010, mainly as a result of increased funding from PMI. The scaling up of IRS coverage in sub-Saharan Africa has been successful in several epidemiological settings and contributed to reduced malaria transmission rates. However, the spread and intensification of pyrethroid resistance in malaria vectors led many control programmes to spray alternative insecticides. Between 2009 and 2013, pyrethroid spraying decreased from 87 % (13/15) of PMI-funded countries conducting IRS to 44 % (7/16), while bendiocarb use increased from 7 % (1/15) to 56 % (9/16). Long-lasting pirimiphos-methyl CS received WHOPES recommendation in 2013 and was scheduled to be sprayed in 85 % (11/13) of PMI-funded countries conducting IRS in 2015. The gradual replacement of relatively inexpensive pyrethroids, firstly with bendiocarb (carbamate) and subsequently with pirimiphos methyl CS (organophosphate), has contributed to the downscaling of most PMI-funded IRS programmes. Overall, there was a 53 % decrease in the number of structures sprayed between years of peak coverage and 2015, down from 9.04 million to 4.26 million structures. Sizeable reductions in the number of structures sprayed were reported in Madagascar (56 %, 576,320–254,986), Senegal (64 %, 306,916–111,201), Tanzania (68 %, 1,224,095–389,714) and Zambia (63 %, 1,300,000–482,077), while in Angola, Liberia and Malawi PMI-funded spraying was suspended. The most commonly cited reason was increased cost of pesticides, as vector resistance necessitated switching from pyrethroids to organophosphates. There are worrying preliminary reports of malaria resurgence following IRS withdrawal in parts of Benin, Tanzania and Uganda. The increase in malaria cases following the end of the Global Malaria Eradication Programme in 1969 highlights the fragility of such gains when control efforts are weakened. At present there are several countries reliant on organophosphates and carbamates for IRS, and increasing incipient resistance is a serious threat that could result in IRS no longer being viable. A portfolio of new cost-effective insecticides with different modes of action is urgently needed.

The Effect of Indoor Residual Spraying on the Prevalence of Malaria Parasite Infection, Clinical Malaria and Anemia in an Area of Perennial Transmission and Moderate Coverage of Insecticide Treated Nets in Western Kenya.

BackgroundInsecticide treated nets (ITNs) and indoor residual spraying (IRS) have been scaled up for malaria prevention in sub-Saharan Africa. However, there are few studies on the benefit of implementing IRS in areas with moderate to high coverage of ITNs. We evaluated the impact of an IRS program on malaria related outcomes in western Kenya, an area of intense perennial malaria transmission and moderate ITN coverage (55–65% use of any net the previous night).MethodsThe Kenya Division of Malaria Control, with support from the US President’s Malaria Initiative, conducted IRS in one lowland endemic district with moderate coverage of ITNs. Surveys were conducted in the IRS district and a neighboring district before IRS, after one round of IRS in July-Sept 2008 and after a second round of IRS in April-May 2009. IRS was conducted with pyrethroid insecticides. At each survey, 30 clusters were selected for sampling and within each cluster, 12 compounds were randomly selected. The primary outcomes measured in all residents of selected compounds included malaria parasitemia, clinical malaria (P. falciparum infection plus history of fever) and anemia (Hb<8) of all residents in randomly selected compounds. At each survey round, individuals from the IRS district were matched to those from the non-IRS district using propensity scores and multivariate logistic regression models were constructed based on the matched dataset.ResultsAt baseline and after one round of IRS, there were no differences between the two districts in the prevalence of malaria parasitemia, clinical malaria or anemia. After two rounds of IRS, the prevalence of malaria parasitemia was 6.4% in the IRS district compared to 16.7% in the comparison district (OR = 0.36, 95% CI = 0.22–0.59, p<0.001). The prevalence of clinical malaria was also lower in the IRS district (1.8% vs. 4.9%, OR = 0.37, 95% CI = 0.20–0.68, p = 0.001). The prevalence of anemia was lower in the IRS district but only in children under 5 years of age (2.8% vs. 9.3%, OR = 0.30, 95% CI = 0.13–0.71, p = 0.006). Multivariate models incorporating both IRS and ITNs indicated that both had an impact on malaria parasitemia and clinical malaria but the independent effect of ITNs was reduced in the district that had received two rounds of IRS. There was no statistically significant independent effect of ITNs on the prevalence of anemia in any age group.ConclusionsBoth IRS and ITNs are effective tools for reducing malaria burden and when implemented in an area of moderate to high transmission with moderate ITN coverage, there may be an added benefit of IRS. The value of adding ITNs to IRS is less clear as their benefits may be masked by IRS. Additional monitoring of malaria control programs that implement ITNs and IRS concurrently is encouraged to better understand how to maximize the benefits of both interventions, particularly in the context of increasing pyrethroid resistance.

Effect of the Ebola-virus-disease epidemic on malaria case management in Guinea, 2014: a cross-sectional survey of health facilities

SummaryBackgroundThe ongoing west Africa Ebola-virus-disease epidemic has disrupted the entire health-care system in affected countries. Because of the overlap of symptoms of Ebola virus disease and malaria, the care delivery of malaria is particularly sensitive to the indirect effects of the current Ebola-virus-disease epidemic. We therefore characterise malaria case management in the context of the Ebola-virus-disease epidemic and document the effect of the Ebola-virus-disease epidemic on malaria case management.MethodsWe did a cross-sectional survey of public health facilities in Guinea in December, 2014. We selected the four prefectures most affected by Ebola virus disease and selected four randomly from prefectures without any reported cases of the disease. 60 health facilities were sampled in Ebola-affected and 60 in Ebola-unaffected prefectures. Study teams abstracted malaria case management indicators from registers for January to November for 2013 and 2014 and interviewed health-care workers. Nationwide weekly surveillance data for suspect malaria cases reported between 2011 and 2014 were analysed independently. Data for malaria indicators in 2014 were compared with previous years.FindingsWe noted substantial reductions in all-cause outpatient visits (by 23 103 [11%] of 214 899), cases of fever (by 20249 [15%] of 131 330), and patients treated with oral (by 22 655 [24%] of 94 785) and injectable (by 5219 [30%] of 17 684) antimalarial drugs in surveyed health facilities. In Ebola-affected prefectures, 73 of 98 interviewed community health workers were operational (74%, 95% CI 65–83) and 35 of 73 were actively treating malaria cases (48%, 36–60) compared with 106 of 112 (95%, 89–98) and 102 of 106 (96%, 91–99), respectively, in Ebola-unaffected prefectures. Nationwide, the Ebola-virus-disease epidemic was estimated to have resulted in 74 000 (71 000–77 000) fewer malaria cases seen at health facilities in 2014.InterpretationThe reduction in the delivery of malaria care because of the Ebola-virus-disease epidemic threatens malaria control in Guinea. Untreated and inappropriately treated malaria cases lead to excess malaria mortality and more fever cases in the community, impeding the Ebola-virus-disease response.FundingGlobal Fund to Fight AIDS, Tuberculosis and Malaria, and President's Malaria Initiative.

Subtle changes in Plasmodium falciparum infection complexity following enhanced intervention in Malawi

With support from the Global Fund, the United States President's Malaria Initiative (PMI) and other cooperating partners, Malawi is implementing a comprehensive malaria control programme involving indoor residual spraying in targeted districts, universal coverage with insecticide-treated bed nets, use of rapid diagnostic tests to confirm the clinical diagnosis of malaria and use of the highly effective artemisinin-based combination therapy, artemether-lumefantrine (AL), as the first-line treatment for malaria. We genotyped 24 genome-wide single nucleotide polymorphisms (SNPs) in Plasmodium falciparum infections (n=316) sampled from a single location in Malawi before (2006 and 2007) and after enhanced intervention (2008 and 2012). The SNP data generated were used to examine temporal changes in the proportion of multiple-genotype infections (MIs), mean number of heterozygous SNPs within MIs, parasite genetic diversity (expected heterozygosity and genotypic richness), multilocus linkage disequilibrium and effective population size (Ne). While the proportion of MIs, expected heterozygosity, genotypic richness, multilocus linkage disequilibrium and Ne were unchanged over time, the mean number (±standard deviation) of heterozygous SNPs within MIs decreased significantly (p=0.01) from 9(±1) in 2006 to 7(±1) in 2012. These findings indicate that the genetic diversity of P. falciparum malaria parasites in this area remains high, suggesting that only subtle gains, if any, have been made in reducing malaria transmission. Continued surveillance is required to evaluate the impact of malaria control interventions in this area and the rest of Malawi, and to better target control interventions.

Quantifying filariasis and malaria control activities in relation to lymphatic filariasis elimination: a multiple intervention score map (MISM) for Malawi

To quantify the geographical extent of filariasis and malaria control interventions impacting lymphatic filariasis (LF) in Malawi and to produce a multiple intervention score map (MISM) for prioritising surveillance and intervention strategies. Interventions included mass drug administration (MDA) for LF and onchocerciasis, and bed nets and indoor residual spraying (IRS) for malaria. District and subdistrict-level data were obtained from the Ministry of Health in Malawi, the Demographic and Health Survey (DHS) and President's Malaria Initiative reports. Single intervention scores were calculated for each variable based on population coverage thresholds, and these were combined in a weighted sum to form a multiple intervention score, which was then used to produce maps, that is MISMs. Districts were further classified into four groups based on the combination of their baseline LF prevalence and multiple intervention score. The district- and subdistrict-level MISMs highlighted specific areas that have received high and low coverage of LF-impacting interventions. High coverage areas included the LF-onchocerciasis endemic areas in the southern region of the country and areas along the shores of Lake Malawi, where malaria vector control had been prioritised. Three districts with high baseline LF prevalence measures but low coverage of multiple interventions were identified and considered to be most at risk of ongoing transmission or re-emergence. These maps and district classifications will be used by LF programme managers to identify and target high-risk areas that may not have received adequate LF-impacting interventions to interrupt the transmission of the disease.

Suppression of malaria transmission and increases in economic productivity in African countries from 2007 to 2011.

To test the assumption that reductions in malaria in Africa will increase economic productivity, a correlation-regression analysis was conducted to evaluate the impact of expenditures by the US President's Malaria Initiative for Africa (PMI), and increases in the economic productivity of countries included in the PMI. For the 12 most representative countries the per capita expenditures for malaria suppression in the 2011 budget of the PMI were compared with observed increases in per capita economic productivity. The measure of economic productivity used was the per capita Gross Domestic Product (GDP) for the period 2007 to 2011. With a mean annual expenditure for suppressing malaria slightly above 1 US dollar per capita (range 0.44-3.40), there was a positive but weak correlation of higher expenditures with increased economic productivity. The correlation coefficient r was 0.5. The increase in per capita GDP in these countries over the 4-year period varied between 60 and 200 USD. The slope of the regression line and thus the ratio of benefits to cost from this programme varied slightly between ecologic zones, but the mean was 6.75 to 1. This meant that there was an increase in per capita GDP of $6.75 for every $1 invested per capita in suppressing malaria. The high benefits to cost ratio from the PMI makes suppression of malaria by methods used by the initiative potentially an attractive investment, at least for the near future while the biocides and drugs deployed are still effective.

Economic aspects of suppressing malaria in Africa.

Suppressing malaria in Africa is costly, but is it a good way for international agencies to use their funds, or alternatively, for the African nations that are the direct beneficiaries? Unfortunately, the current ephemeral methods in the malaria strategy of the World Health Organization have required continuous and rising expenditures by international donors who were beginning to lose interest by 2010. To avoid becoming hostage to international economic limitations, African countries might want to consider suppressing malaria themselves, and might want to add permanent and lasting methods to the WHO strategy. The purpose of this study was to determine whether investments in suppressing malaria might produce significant benefits for African nations. Two epidemiologic analyses were used in parallel to evaluate data from Africa: a before-after comparison of countries treated under the US President's Malaria Initiative for Africa (PMI), and a simultaneous comparison of treated-untreated countries. From 2007 to 2012, relative increases in population and gross domestic product (GDP) were greater in 14 countries treated as part of PMI than in 9 similar, but untreated countries. In the treated countries the relative increase in the GDP of 0.61 before malaria suppression rose to 0.64 afterwards; whereas in the untreated countries it fell from 0.67 to 0.56. The increase in GDP in the 14 treated countries that was attributable to malaria suppression over the 5-year interval was about $4.77 billion. During that period, the mean cost of suppressing malaria had been about $1.43 billion, indicating a return on the investment of 3.4 to 1. However, the costs began rising steeply in 2012. Malaria suppression might be worthwhile for African countries to undertake themselves, as long as the biocides and drugs in current use remain effective.

Secondary analysis of national and subnational survey data to evaluate the impact of the scale-up of malaria control interventions in Malawi, 2000–10

BackgroundMalaria control interventions, including insecticide-treated nets (ITNs), were scaled up nationwide in Malawi during 2000–10. We assessed trends and associations of ITN coverage, malaria morbidity, and all-cause mortality in children under 5 years of age under programmatic conditions in Malawi during 2000–10. MethodsTrends in household ITN ownership, malaria parasitaemia, and anaemia (haemoglobin <80 g/L) prevalence, and all-cause under-5 mortality per 1000 livebirths (ACCM) were assessed from national population-based household surveys conducted during 2000–10. Random-effects logistic regression models assessed the association between household ITN ownership and malaria parasitaemia, or anaemia prevalence in children 6–30 months of age using subnational anaemia and parasitaemia survey data. We employed a random-effects Poisson regression model to assess the association between district ITN distributions and child malaria cases using integrated disease surveillance and response (IDSR) facility data. At the district level, we used a Poisson regression model to assess the association between household ITN ownership and child mortality using data from the 2010 Malawi Demographic and Health Survey. FindingsHousehold ITN ownership increased from 27·4% (95% CI 25·9–29·0) in 2004, to 56·8% (55·6–58·1) in 2010. Malaria parasitaemia decreased from 60·5% (95% CI 53·0–68·0) in 2001, to 20·4% (15·7–25·1) in 2009, in children aged 6–35 months. Anaemia decreased from 20·4% (95% CI 17·3–24·0) in 2004, to 13·1% (11·0–15·4) in 2010, in children aged 6–23 months. ACCM decreased by 41% from 188·3 deaths per 1000 livebirths (95% CI 179·2–197·3) during 1996–2000, to 112·1 per 1000 livebirths (106·1–118·0) during 2006–10. Household ITN ownership was protective against malaria parasitaemia (odds ratio 0·81, 95% CI 0·72–0·92) and anaemia (0·77, 0·70–0·86) after controlling for other covariates. ITN distributions per 1000 population were not significantly associated with malaria cases at IDSR facilities. District-level household ITN ownership was significantly associated with child survival (incidence rate ratio 0·55, 95% CI 0·31–0·99) after controlling for other covariates. InterpretationHousehold ITN ownership was protective against malaria parasitaemia, anaemia, and child mortality. Scale-up of malaria control interventions during 2000–10 was likely associated with improved child survival in Malawi. FundingFinancial support for this study was received from the United States President's Malaria Initiative.