Costs and cost-effectiveness of delivering intermittent preventive treatment through schools in western Kenya

Targeted Drug Administration to Reduce Malaria Transmission: A Systematic Review and Meta-Analysis

In low- to very low-malaria transmission areas, most infections may be accrued within specific groups whose behaviors or occupations put them at increased risk of infection. If these infections comprise a large proportion of the reservoir of infection, targeting interventions to these groups could reduce transmission at the population level. We conducted a systematic review to assess the impact of providing antimalarials to groups of individuals at increased risk of malaria whose infections were considered to comprise a large proportion of the local reservoir of infections (targeted drug administration [TDA]). A literature search was conducted in March 2021 and updated in April 2022. Two reviewers screened titles, abstracts, and full-text records. The Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the certainty of the evidence (CoE) for each outcome. Out of 2,563 records, we identified five studies for inclusion: two cluster-randomized controlled trials (cRCTs) in Uganda and Kenya; one controlled before-after study in Ghana; and two uncontrolled before-after studies in Sri Lanka and Greece. Compared with no intervention, TDA resulted in little to no difference in the prevalence of infection at the population level (risk ratio [RR]: 0.85, 95% CI: 0.73-1.00; one cRCT, high CoE), although TDA likely resulted in a large reduction in prevalence among those targeted by the intervention (RR: 0.15, 95% CI: 0.06-0.38; two cRCTs, moderate CoE). Although TDA may reduce the burden of malaria among those receiving antimalarials, we found no evidence that it reduces transmission at the population level.

Contextual Factors to Improve Implementation of Malaria Chemoprevention in Children: A Systematic Review

Malaria remains a leading cause of childhood morbidity and mortality in sub-Saharan Africa, particularly among children under 5 years of age. To help address this challenge, the WHO recommends chemoprevention for certain populations. For children and infants, the WHO recommends seasonal malaria chemoprevention (SMC), perennial malaria chemoprevention (PMC; formerly intermittent preventive treatment in infants [IPTi]), and, more recently, intermittent preventive treatment in school children (IPTsc). This review describes the contextual factors, including feasibility, acceptability, health equity, financial considerations, and values and preferences, that impact implementation of these strategies. A systematic search was conducted on July 5, 2022, and repeated April 13, 2023, to identify relevant literature. Two reviewers independently screened titles for eligibility, extracted data from eligible articles, and identified and summarized themes. Of 6,295 unique titles identified, 65 were included. The most frequently evaluated strategy was SMC (n = 40), followed by IPTi (n = 18) and then IPTsc (n = 6). Overall, these strategies were highly acceptable, although with IPTsc, there were community concerns with providing drugs to girls of reproductive age and the use of nonmedical staff for drug distribution. For SMC, door-to-door delivery resulted in higher coverage, improved caregiver acceptance, and reduced cost. Lower adherence was noted when caregivers were charged with giving doses 2 and 3 unsupervised. For SMC and IPTi, travel distances and inclement weather limited accessibility. Sensitization and caregiver education efforts, retention of high-quality drug distributors, and improved transportation were key to improving coverage. Additional research is needed to understand the role of community values and preferences in chemoprevention implementation.

Implementation research of a cluster randomized trial evaluating the implementation and effectiveness of intermittent preventive treatment for malaria using dihydroartemisinin-piperaquine on reducing malaria burden in school-aged children in Tanzania: methodology, challenges, and mitigation

BACKGROUND

It has been more than 20 years since the malaria epidemiologic shift to school-aged children was noted. In the meantime, school-aged children (5-15 years) have become increasingly more vulnerable with asymptomatic malaria prevalence reaching up to 70%, making them reservoirs for subsequent transmission of malaria in the endemic communities. Intermittent Preventive Treatment of malaria in schoolchildren (IPTsc) has proven to be an effective tool to shrink this reservoir. As of 3^rd June 2022, the World Health Organization recommends IPTsc in moderate and high endemic areas. Even so, for decision-makers, the adoption of scientific research recommendations has been stifled by real-world implementation challenges. This study presents methodology, challenges faced, and mitigations used in the evaluation of the implementation of IPTsc using dihydroartemisinin-piperaquine (DP) in three councils (Handeni District Council (DC), Handeni Town Council (TC) and Kilindi DC) of Tanga Region, Tanzania so as to understand the operational feasibility and effectiveness of IPTsc on malaria parasitaemia and clinical malaria incidence.

METHODS

The study deployed an effectiveness-implementation hybrid design to assess feasibility and effectiveness of IPTsc using DP, the interventional drug, against standard of care (control). Wards in the three study councils were the randomization unit (clusters). Each ward was randomized to implement IPTsc or not (control). In all wards in the IPTsc arm, DP was given to schoolchildren three times a year in four-month intervals. In each council, 24 randomly selected wards (12 per study arm, one school per ward) were chosen as representatives for intervention impact evaluation. Mixed design methods were used to assess the feasibility and acceptability of implementing IPTsc as part of a more comprehensive health package for schoolchildren. The study reimagined an existing school health programme for Neglected Tropical Diseases (NTD) control include IPTsc implementation.

RESULTS

The study shows IPTsc can feasibly be implemented by integrating it into existing school health and education systems, paving the way for sustainable programme adoption in a cost-effective manner.

CONCLUSIONS

Through this article other interested countries may realise a feasible plan for IPTsc implementation. Mitigation to any challenge can be customized based on local circumstances without jeopardising the gains expected from an IPTsc programme. Trial registration clinicaltrials.gov, NCT04245033. Registered 28 January 2020, https://clinicaltrials.gov/ct2/show/NCT04245033.

Impact of school-based malaria intervention on primary school teachers' time in Malawi: evidence from a time and motion study

BACKGROUND

School-based health (SBH) programmes that are contingent on primary school teachers are options to increase access to malaria treatment among learners. However, perceptions that provision of healthcare by teachers may be detrimental to teaching activities can undermine efforts to scale up school-based malaria control. The objective of this study was to assess the impact of school-based malaria diagnosis and treatment using the Learner Treatment Kit (LTK) on teachers' time.

METHODS

A time and motion study was conducted in 10 primary schools in rural Malawi. Teachers who had been trained to diagnose and treat uncomplicated malaria were continuously observed in real time during school sessions and the time they spent on all activities were recorded by independent observers before and after LTK implementation. A structured form, programmed digitally, was used for data collection. Paired sample t-tests were used to assess pre-post differences in average hours teachers spent on the following key activities: direct teaching; indirect teaching; administration; LTK and non-teaching tasks. Multivariable repeated measures mixed regression models were used to ascertain impact of LTK on average durations teachers spent on the key activities.

RESULTS

Seventy-four teachers, trained to use LTK, were observed. Their mean age and years of teaching experience were 34.7 and 8.7, respectively. Overall, 739.8 h of teacher observations took place. The average time teachers spent in school before relative to after LTK was 5.8 vs. 4.8 h, p = 0.01. The cumulative percentage of time teachers spent on core teaching activities (teaching and administration) was approximately 76% and did not change substantially before and after LTK. Some 24.3% of teachers' time is spent on non-teaching activities. On average, teachers spent 2.9% of their time providing LTK services daily. Per day, each teacher spent less time on administrative (0.74 vs. 1.07 h, p = 0.02) and non-teaching activities (0.96 vs. 1.41 h, p = 0.01) during LTK compared with the period before LTK.

CONCLUSION

School-based health (SBH) programmes are not detrimental to teaching activities. Teachers manage their time to ensure additional time required for SBH services is not at the expense of teaching duties. Programming and policy implications of tasking teachers with SBH does not have substantial opportunity costs. Teachers should continue delivering SBH programmes to promote learners' health.

Effectiveness and safety of intermittent preventive treatment for malaria using either dihydroartemisinin-piperaquine or artesunate-amodiaquine in reducing malaria related morbidities and improving cognitive ability in school-aged children in Tanzania: A study protocol for a controlled randomised trial

BACKGROUND

In high transmission settings, up to 70% of school-aged children harbour malaria parasites without showing any clinical symptoms. Thus, epidemiologically, school aged children act as a substantial reservoir for malaria transmission. Asymptomatic Plasmodium infections induce inflammation leading to iron deficiency anaemia. Consequently, anaemia retards child growth, predisposes children to other diseases and reduces cognitive potential that could lead to poor academic performance. School aged children become increasingly more vulnerable as compared to those aged less than five years due to delayed acquisition of protective immunity. None of the existing Intermittent Preventive Treatment (IPT) strategies is targeting school-aged children. Here, we describe the study protocol of a clinical trial conducted in north-eastern Tanzania to expand the IPT by assessing the effectiveness and safety of two antimalarial drugs, Dihydroartemisinin-Piperaquine (DP) and Artesunate-Amodiaquine (ASAQ) in preventing malaria related morbidities in school-aged children (IPTsc) living in a high endemic area.

METHODS/DESIGN

The trial is a phase IIIb, individual randomized, open label, controlled trial enrolling school children aged 5-15 years, who receive either DP or ASAQ or control (no drug), using a "balanced block design" with the "standard of care" arm as reference. The interventional treatments are given three times a year for the first year. A second non-interventional year will assess possible rebound effects. Sample size was estimated to 1602 school children (534 per group) from selected primary schools in an area with high malaria endemicity. Thick and thin blood smears (to measure malaria parasitaemia using microscope) were obtained prior to treatment at baseline, and will be obtained again at month 12 and 20 from all participants. Haemoglobin concentration using a haemoglobinometer (HemoCue AB, Sweden) will be measured four monthly. Finger-prick blood (dried bloodspot-DBS) prepared on Whatman 3 M filter paper, will be used for sub-microscopic malaria parasite detection usingPCR, detect markers of drug resistance (using next generation sequencing (NGS) technology), and malaria serological assays (using enzyme-linked immunosorbent assay, ELISA). To determine the benefit of IPTsc on cognitive and psychomotor ability test of everyday attention for children (TEA-Ch) and a '20 m Shuttle run' respectively, will be conducted at baseline, month 12 and 20. The primary endpoints are change in mean haemoglobin from baseline concentration and reduction in clinical malaria incidence at month 12 and 20 of follow up. Mixed design methods are used to assess the acceptability, cost-effectiveness and feasibility of IPTsc as part of a more comprehensive school children health package. Statistical analysis will be in the form of multilevel modelling, owing to repeated measurements and clustering effect of participants.

DISCUSSION

Malaria intervention using IPTsc strategy may be integrated in the existing national school health programme. However, there is limited systematic evidence to assess the effectiveness and operational feasibility of this approach. School-aged children are easily accessible in most endemic malaria settings. The evidence from this study will guide the implementation of the strategy to provide complementary approach to reduce malaria related morbidity, anaemia and contribute to the overall burden reduction.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT03640403, registered on Aug 21, 2018, prospectively registered.Url https://www.clinicaltrials.gov/ct2/show/NCT03640403?term=NCT03640403&rank=1.

Large-scale delivery of seasonal malaria chemoprevention to children under 10 in Senegal: an economic analysis

Seasonal Malaria Chemoprevention (SMC) is recommended for children under 5 in the Sahel and sub-Sahel. The burden in older children may justify extending the age range, as has been done effectively in Senegal. We examine costs of door-to-door SMC delivery to children up to 10 years by community health workers (CHWs). We analysed incremental financial and economic costs at district level and below from a health service perspective. We examined project accounts and prospectively collected data from 405 CHWs, 46 health posts, and 4 district headquarters by introducing questionnaires in advance and completing them after each monthly implementation round. Affordability was explored by comparing financial costs of SMC to relevant existing health expenditure levels. Costs were disaggregated by administration month and by health service level. We used linear regression models to identify factors associated with cost variation between health posts. The financial cost to administer SMC to 180 000 children over one malaria season, reaching ∼93% of children with all three intended courses of SMC was $234 549 (constant 2010 USD) or $0.50 per monthly course administered. Excluding research-participation incentives, the financial cost was $0.32 per resident (all ages) in the catchment area, which is 1.2% of Senegal's general government expenditure on health per capita. Economic costs were 18.7% higher than financial costs at $278 922 or $0.59 per course administered and varied widely between health posts, from $0.38 to $2.74 per course administered. Substantial economies of scale across health posts were found, with the smallest health posts incurring highest average costs per monthly course administered. SMC for children up to 10 is likely to be affordable, particularly where it averts substantial curative care costs. Estimates of likely costs and cost-effectiveness of SMC in other contexts must account for variation in average costs across delivery months and health posts.

Cost analysis of a school-based comprehensive malaria program in primary schools in Sikasso region, Mali

Background

The expansion of malaria prevention and control to school-aged children is receiving increasing attention, but there are still limited data on the costs of intervention. This paper analyses the costs of a comprehensive school-based intervention strategy, delivered by teachers, that included participatory malaria educational activities, distribution of long lasting insecticide-treated nets (LLIN), and Intermittent Parasite Clearance in schools (IPCs) in southern Mali.

Methods

Costs were collected alongside a randomised controlled trial conducted in 80 primary schools in Sikasso Region in Mali in 2010-2012. Cost data were compiled between November 2011 and March 2012 for the 40 intervention schools (6413 children). A provider perspective was adopted. Using an ingredients approach, costs were classified by cost category and by activity. Total costs and cost per child were estimated for the actual intervention, as well as for a simpler version of the programme more suited for scale-up by the government. Univariate sensitivity analysis was performed.

Results

The economic cost of the comprehensive intervention was estimated to $10.38 per child (financial cost $8.41) with malaria education, LLIN distribution and IPCs costing $2.13 (20.5%), $5.53 (53.3%) and $2.72 (26.2%) per child respectively. Human resources were found to be the key cost driver, and training costs were the greatest contributor to overall programme costs. Sensitivity analysis showed that an adapted intervention delivering one LLIN instead of two would lower the economic cost to $8.66 per child; and that excluding LLIN distribution in schools altogether, for example in settings where malaria control already includes universal distribution of LLINs at community-level, would reduce costs to $4.89 per child.

Conclusions

A comprehensive school-based control strategy may be a feasible and affordable way to address the burden of malaria among schoolchildren in the Sahel.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4490-6) contains supplementary material, which is available to authorized users.

Global investment targets for malaria control and elimination between 2016 and 2030

Background

Access to malaria control interventions falls short of universal health coverage. The Global Technical Strategy for malaria targets at least 90% reduction in case incidence and mortality rates, and elimination in 35 countries by 2030. The potential to reach these targets will be determined in part by investments in malaria. This study estimates the financing required for malaria control and elimination over the 2016-2030 period.

Methods

A mathematical transmission model was used to explore the impact of increasing intervention coverage on burden and costs. The cost analysis took a public provider perspective covering all 97 malaria endemic countries and territories in 2015. All control interventions currently recommended by the WHO were considered. Cost data were sourced from procurement databases, the peer-reviewed literature, national malaria strategic plans, the WHO-CHOICE project and key informant interviews.

Results

Annual investments of $6.4 billion (95% uncertainty interval (UI $4.5-$9.0 billion)) by 2020, $7.7 billion (95% UI $5.4-$10.9 billion) by 2025 and $8.7 billion (95% UI $6.0-$12.3 billion) by 2030 will be required to reach the targets set in the Global Technical Strategy. These are equivalent to annual investment per person at risk of malaria of US$3.90 by 2020, US$4.30 by 2025 and US$4.40 by 2030, compared with US$2.30 if interventions were sustained at current coverage levels. The 20 countries with the highest burden in 2015 will require 88% of the total investment.

Conclusions

Given the challenges in increasing domestic and international funding, the efficient use of currently available resources should be a priority.

Malaria in school-age children in Africa: an increasingly important challenge

School-age children have attracted relatively little attention as a group in need of special measures to protect them against malaria. However, increasing success in lowering the level of malaria transmission in many previously highly endemic areas will result in children acquiring immunity to malaria later in life than has been the case in the past. Thus, it can be anticipated that in the coming years there will be an increase in the incidence of both uncomplicated and severe malaria in school-age children in many previously highly endemic areas. In this review, which focuses primarily on Africa, recent data on the prevalence of malaria parasitaemia and on the incidence of clinical malaria in African school-age children are presented and evidence that malaria adversely effects school performance is reviewed. Long-lasting insecticide treated bednets (LLIN) are an effective method of malaria control but several studies have shown that school-age children use LLINs less frequently than other population groups. Antimalarial drugs are being used in different ways to control malaria in school-age children including screening and treatment and intermittent preventive treatment. Some studies of chemoprevention in school-age children have shown reductions in anaemia and improved school performance but this has not been the case in all trials and more research is needed to identify the situations in which chemoprevention is likely to be most effective and, in these situations, which type of intervention should be used. In the longer term, malaria vaccines may have an important role in protecting this important section of the community from malaria. Regardless of the control approach selected, it is important this is incorporated into the overall programme of measures being undertaken to enhance the health of African school-age children.

The role of nutrition in integrated programs to control neglected tropical diseases

There are strong and direct relationships between undernutrition and the disease caused by infectious organisms, including the diverse pathogens labeled as neglected tropical diseases (NTDs). Undernutrition increases the risk of infection, the severity of disease and the risk that children will die, while the physical damage, loss of appetite, and host responses during chronic infection can contribute substantially to undernutrition. These relationships are often synergistic. This opinion article examines the role of nutrition in controlling NTDs and makes the point that mass drug treatment--the major strategy currently proposed to control several diseases--is crucial to controlling disease and transmission, but is only the start of the process of physical recovery. Without adequate energy and nutrients to repair damaged tissues or recover lost growth and development, the benefits of treatment may not be evident quickly; the effects of control programs may be not appreciated by beneficiaries; while vulnerability to reinfection and disease may not be reduced. There is substantial potential for nutritional interventions to be added to large-scale programs to deliver drug treatments and thereby contribute, within a broad strategy of public health interventions and behavior change activities, to controlling and preventing NTDs in populations, and to restoring their health.

Malaria treatment and prophylaxis in endemic and nonendemic countries: evidence on strategies and their cost–effectiveness

Artemisinin combination treatment is currently the preferred treatment strategy to combat malaria. However, the drug costs are considerably higher than for previously used therapies. This review discusses the cost–effectiveness of current malaria treatment and prophylaxis in endemic and nonendemic countries. For endemic countries, a systematic search for economic evaluations (i.e., cost–effectiveness, cost–utility and cost–benefit analyses) was conducted, looking at the use of Artemisinin combination treatments in children, pregnant women and other adults. In total, 24 studies were identified investigating the cost–effectiveness of malaria treatments with the focus on uncomplicated malaria, severe or prereferral treatment, all in combination with adequate diagnosis, and malaria prevention by intermittent preventive treatment, respectively. In areas with both Plasmodium falciparum and Plasmodium vivax transmission, artemether–lumefantrine and dihydroartemisinin–piperaquine, respectively, are currently the most cost-effective treatment options. Treatment of severe malaria with artesunate is more cost effective compared with treatment with quinine. For patients that live more than 6 h away from an appropriate healthcare facility, prereferral treatment proved to be more cost-effective compared with no prereferral intervention. Cost–effectiveness of intermittent preventive treatment in pregnant women (IPTp) was dependent an clinical attendance. IPT in infants with sulphadoxine–pyrimethamine (SP) is cost effective in sites with high malaria transmission. IPT in children with artesunate (AS + SP), amodiaquine (AQ) + SPQ or SP alone is a cost effective and safe intervention for reducing the burden of malaria in children in areas with markedly seasonal malaria transmission. Although there is a need for it, little is known about the cost–effectiveness of current approaches to malaria therapy in nonendemic countries and the cost–effectiveness of antimalarial chemoprophylaxis.

Cost-effectiveness of intermittent preventive treatment of malaria in infants (IPTi) for averting anaemia in Gabon: a comparison between intention to treat and according to protocol analyses

Background

In Gabon, the impact of intermittent preventive treatment of malaria in infants (IPTi) was not statistically significant on malaria reduction, but the impact on moderate anaemia was, with some differences between the intention to treat (ITT) and the according to protocol (ATP) trial analyses. Specifically, ATP was statistically significant, while ITT analysis was borderline. The main reason for the difference between ITT and ATP populations was migration.

Methods

This study estimates the cost-effectiveness of IPTi on the reduction of anaemia in Gabon, comparing results of the ITT and the ATP clinical trial analyses. Threshold analysis was conducted to identify when the intervention costs and protective efficacy of IPTi for the ATP cohort equalled the ITT cost-effectiveness ratio.

Results

Based on IPTi intervention costs, the cost per episode of moderate anaemia averted was US$12.88 (CI 95% 4.19, 30.48) using the ITT analysis and US$11.30 (CI 95% 4.56, 26.66) using the ATP analysis. In order for the ATP results to equal the cost-effectiveness of ITT, total ATP intervention costs should rise from 118.38 to 134 US$ ATP or the protective efficacy should fall from 27% to 18.1%. The uncertainty surrounding the cost-effectiveness ratio using ITT trial results was higher than using ATP results.

Conclusions

Migration implies great challenges in the organization of health interventions that require repeat visits in Gabon. This was apparent in the study as the cost-effectiveness of IPTp-SP worsened when drop out from the prevention was taken into account. Despite such challenges, IPTi was both inexpensive and efficacious in averting cases of moderate anaemia in infants.

Cost analysis of school-based intermittent screening and treatment of malaria in Kenya

Background

The control of malaria in schools is receiving increasing attention, but there remains currently no consensus as to the optimal intervention strategy. This paper analyses the costs of intermittent screening and treatment (IST) of malaria in schools, implemented as part of a cluster-randomized controlled trial on the Kenyan coast.

Methods

Financial and economic costs were estimated using an ingredients approach whereby all resources required in the delivery of IST are quantified and valued. Sensitivity analysis was conducted to investigate how programme variation affects costs and to identify potential cost savings in the future implementation of IST.

Results

The estimated financial cost of IST per child screened is US$ 6.61 (economic cost US$ 6.24). Key contributors to cost were salary costs (36%) and malaria rapid diagnostic tests (RDT) (22%). Almost half (47%) of the intervention cost comprises redeployment of existing resources including health worker time and use of hospital vehicles. Sensitivity analysis identified changes to intervention delivery that can reduce programme costs by 40%, including use of alternative RDTs and removal of supervised treatment. Cost-effectiveness is also likely to be highly sensitive to the proportion of children found to be RDT-positive.

Conclusion

In the current context, school-based IST is a relatively expensive malaria intervention, but reducing the complexity of delivery can result in considerable savings in the cost of intervention.

(Costs are reported in US$ 2010).

Determinants of the cost-effectiveness of intermittent preventive treatment for malaria in infants and children

BACKGROUND

Trials of intermittent preventive treatment in infants (IPTi) and children (IPTc) have shown promising results in reducing malaria episodes but with varying efficacy and cost-effectiveness. The effects of different intervention and setting characteristics are not well known. We simulate the effects of the different target age groups and delivery channels, seasonal or year-round delivery, transmission intensity, seasonality, proportions of malaria fevers treated and drug characteristics.

METHODS

We use a dynamic, individual-based simulation model of Plasmodium falciparum malaria epidemiology, antimalarial drug action and case management to simulate DALYs averted and the cost per DALY averted by IPTi and IPTc. IPT cost components were estimated from economic studies alongside trials.

RESULTS

IPTi and IPTc were predicted to be cost-effective in most of the scenarios modelled. The cost-effectiveness is driven by the impact on DALYs, particularly for IPTc, and the low costs, particularly for IPTi which uses the existing delivery strategy, EPI. Cost-effectiveness was predicted to decrease with low transmission, badly timed seasonal delivery in a seasonal setting, short-acting and more expensive drugs, high frequencies of drug resistance and high levels of treatment of malaria fevers. Seasonal delivery was more cost-effective in seasonal settings, and year-round in constant transmission settings. The difference was more pronounced for IPTc than IPTi due to the different proportions of fixed costs and also different assumed drug spacing during the transmission season. The number of DALYs averted was predicted to decrease as a target five-year age-band for IPTc was shifted from children under 5 years into older ages, except at low transmission intensities.

CONCLUSIONS

Modelling can extend the information available by predicting impact and cost-effectiveness for scenarios, for outcomes and for multiple strategies where, for practical reasons, trials cannot be carried out. Both IPTi and IPTc are generally cost-effective but could be rendered cost-ineffective by characteristics of the setting, drug or implementation.

Two strategies for the delivery of IPTc in an area of seasonal malaria transmission in the Gambia: a randomised controlled trial

BACKGROUND

The Expanded Programme on Immunisation (EPI) provides an effective way of delivering intermittent preventive treatment for malaria (IPT) to infants. However, it is uncertain how IPT can be delivered most effectively to older children. Therefore, we have compared two approaches to the delivery of IPT to Gambian children: distribution by village health workers (VHWs) or through reproductive and child health (RCH) trekking teams. In rural areas, RCH trekking teams provide most of the health care to children under the age of 5 years in the Infant Welfare Clinic, and provide antenatal care for pregnant women.

METHODS AND FINDINGS

During the 2006 malaria transmission season, the catchment populations of 26 RCH trekking clinics in The Gambia, each with 400-500 children 6 years of age and under, were randomly allocated to receive IPT from an RCH trekking team or from a VHW. Treatment with a single dose of sulfadoxine pyrimethamine (SP) plus three doses of amodiaquine (AQ) were given at monthly intervals during the malaria transmission season. Morbidity from malaria was monitored passively throughout the malaria transmission season in all children, and a random sample of study children from each cluster was examined at the end of the malaria transmission season. The primary study endpoint was the incidence of malaria. Secondary endpoints included coverage of IPTc, mean haemoglobin (Hb) concentration, and the prevalence of asexual malaria parasitaemia at the end of malaria transmission period. Financial and economic costs associated with the two delivery strategies were collected and incremental cost and effects were compared. A nested case-control study was used to estimate efficacy of IPT treatment courses. Treatment with SP plus AQ was safe and well tolerated. There were 49 cases of malaria with parasitaemia above 5,000/µl in the areas where IPT was delivered through RCH clinics and 21 cases in the areas where IPT was delivered by VHWs, (incidence rates 2.8 and 1.2 per 1,000 child months, respectively, rate difference 1.6 [95% confidence interval (CI) -0.24 to 3.5]). Delivery through VHWs achieved a substantially higher coverage level of three courses of IPT than delivery by RCH trekking teams (74% versus 48%, a difference of 27% [95% CI 16%-38%]). For both methods of delivery, coverage was unrelated to indices of wealth, with similar coverage being achieved in the poorest and wealthiest groups. The prevalence of anaemia was low in both arms of the trial at the end of the transmission season. Efficacy of IPTc against malaria during the month after each treatment course was 87% (95% CI 54%-96%). Delivery of IPTc by VHWs was less costly in both economic and financial terms than delivery through RCH trekking teams, resulting in incremental savings of US$872 and US$1,244 respectively. The annual economic cost of delivering at least the first dose of each course of IPTc was US$3.47 and US$1.63 per child using trekking team and VHWs respectively.

CONCLUSIONS

In this setting in The Gambia, delivery of IPTc to children 6 years of age and under by VHWs is more effective and less costly than delivery through RCH trekking clinics.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00376155. Please see later in the article for the Editors' Summary.

Improving educational achievement and anaemia of school children: design of a cluster randomised trial of school-based malaria prevention and enhanced literacy instruction in Kenya

BACKGROUND

Improving the health of school-aged children can yield substantial benefits for cognitive development and educational achievement. However, there is limited experimental evidence on the benefits of school-based malaria prevention or how health interventions interact with other efforts to improve education quality. This study aims to evaluate the impact of school-based malaria prevention and enhanced literacy instruction on the health and educational achievement of school children in Kenya.

DESIGN

A factorial, cluster randomised trial is being implemented in 101 government primary schools on the coast of Kenya. The interventions are (i) intermittent screening and treatment of malaria in schools by public health workers and (ii) training workshops and support for teachers to promote explicit and systematic literacy instruction. Schools are randomised to one of four groups: receiving either (i) the malaria intervention alone; (ii) the literacy intervention alone; (iii) both interventions combined; or (iv) control group where neither intervention is implemented. Children from classes 1 and 5 are randomly selected and followed up for 24 months. The primary outcomes are educational achievement and anaemia, the hypothesised mediating variables through which education is affected. Secondary outcomes include malaria parasitaemia, school attendance and school performance. A nested process evaluation, using semi-structured interviews, focus group discussion and a stakeholder analysis will investigate the community acceptability, feasibility and cost-effectiveness of the interventions.

DISCUSSION

Across Africa, governments are committed to improve health and education of school-aged children, but seek clear policy and technical guidance as to the optimal approach to address malaria and improved literacy. This evaluation will be one of the first to simultaneously evaluate the impact of health and education interventions in the improvement of educational achievement. Reflection is made on the practical issues encountered in conducting research in schools in Africa.

TRIAL REGISTRATION

National Institutes of Health NCT00878007.

Cost effectiveness of seasonal intermittent preventive treatment using amodiaquine & artesunate or sulphadoxine-pyrimethamine in Ghanaian children

BACKGROUND

Intermittent preventive treatment for malaria in children (IPTc) involves the administration of a full course of an anti-malarial treatment to children under 5 years old at specified time points regardless of whether or not they are known to be infected, in areas where malaria transmission is seasonal. It is important to determine the costs associated with IPTc delivery via community based volunteers and also the potential savings to health care providers and caretakers due to malaria episodes averted as a consequence of IPTc.

METHODS

Two thousand four hundred and fifty-one children aged 3-59 months were randomly allocated to four groups to receive: three days of artesunate plus amodiaquine (AS+AQ) monthly, three days of AS+AQ bimonthly, one dose of sulphadoxine-pyrimethamine (SP) bi-monthly or placebo. This paper focuses on incremental cost effectiveness ratios (ICERs) of the three IPTc drug regimens as delivered by community based volunteers (CBV) in Hohoe, Ghana compared to current practice, i.e. case management in the absence of IPTc. Financial and economic costs from the publicly funded health system perspective are presented. Treatment costs borne by patients and their caretakers are also estimated to present societal costs. The costs and effects of IPTc during the intervention period were considered with and without a one year follow up. Probabilistic sensitivity analysis was undertaken to account for uncertainty.

RESULTS

Economic costs per child receiving at least the first dose of each course of IPTc show SP bimonthly, at US$8.19, is the cheapest to deliver, followed by AS+AQ bimonthly at US$10.67 and then by AS+AQ monthly at US$14.79. Training, drug delivery and supervision accounted for approximately 20-30% each of total unit costs. During the intervention period AS & AQ monthly was the most cost effective IPTc drug regimen at US$67.77 (61.71-74.75, CI 95%) per malaria case averted based on intervention costs only, US$64.93 (58.92-71.92, CI 95%) per malaria case averted once the provider cost savings are included and US$61.00 (54.98, 67.99, CI 95%) when direct household cost savings are also taken into account. SP bimonthly was US$105.35 (75.01-157.31, CI 95%) and AS & AQ bimonthly US$211.80 (127.05-399.14, CI 95%) per malaria case averted based on intervention costs only. The incidence of malaria in the post intervention period was higher in children who were <1 year old when they received AS+AQ monthly compared to the placebo group leading to higher cost effectiveness ratios when one year follow up is included. The cost per child enrolled fell considerably when modelled to district level as compared to those encountered under trial conditions.

CONCLUSIONS

We demonstrate how cost-effective IPTc is using three different drug regimens and the possibilities for reducing costs further if the intervention was to be scaled up to the district level. The need for effective training, drug delivery channels and supervision to support a strong network of community based volunteers is emphasised.

The cost-effectiveness of intermittent preventive treatment for malaria in infants in Sub-Saharan Africa

BACKGROUND

Intermittent preventive treatment in infants (IPTi) has been shown to decrease clinical malaria by approximately 30% in the first year of life and is a promising malaria control strategy for Sub-Saharan Africa which can be delivered alongside the Expanded Programme on Immunisation (EPI). To date, there have been limited data on the cost-effectiveness of this strategy using sulfadoxine pyrimethamine (SP) and no published data on cost-effectiveness using other antimalarials.

METHODS

We analysed data from 5 countries in sub-Saharan Africa using a total of 5 different IPTi drug regimens; SP, mefloquine (MQ), 3 days of chlorproguanil-dapsone (CD), SP plus 3 days of artesunate (SP-AS3) and 3 days of amodiaquine-artesunate (AQ3-AS3).The cost per malaria episode averted and cost per Disability-Adjusted Life-Year (DALY) averted were modeled using both trial specific protective efficacy (PE) for all IPTi drugs and a pooled PE for IPTi with SP, malaria incidence, an estimated malaria case fatality rate of 1.57%, IPTi delivery costs and country specific provider and household malaria treatment costs.

FINDINGS

In sites where IPTi had a significant effect on reducing malaria, the cost per episode averted for IPTi-SP was very low, USD 1.36-4.03 based on trial specific data and USD 0.68-2.27 based on the pooled analysis. For IPTi using alternative antimalarials, the lowest cost per case averted was for AQ3-AS3 in western Kenya (USD 4.62) and the highest was for MQ in Korowge, Tanzania (USD 18.56). Where efficacious, based only on intervention costs, IPTi was shown to be cost effective in all the sites and highly cost-effective in all but one of the sites, ranging from USD 2.90 (Ifakara, Tanzania with SP) to USD 39.63 (Korogwe, Tanzania with MQ) per DALY averted. In addition, IPTi reduced health system costs and showed significant savings to households from malaria cases averted. A threshold analysis showed that there is room for the IPTi-efficacy to fall and still remain highly cost effective in all sites where IPTi had a statistically significant effect on clinical malaria.

CONCLUSIONS

IPTi delivered alongside the EPI is a highly cost effective intervention against clinical malaria with a range of drugs in a range of malaria transmission settings. Where IPTi did not have a statistically significant impact on malaria, generally in low transmission sites, it was not cost effective.

Sulfadoxine-pyrimethamine impairs Plasmodium falciparum gametocyte infectivity and Anopheles mosquito survival

Sulfadoxine-pyrimethamine (SP) is currently the drug of choice for intermittent preventive treatment of Plasmodium falciparum both in pregnancy and infancy. A prolonged parasite clearance time conferred by dhfr and dhps mutations is believed to be responsible for increased gametocyte prevalence in SP treated individuals. However, using a direct feeding assay in Mali, we showed that gametocytes present in peripheral venous blood post-SP treatment had reduced infectivity for Anopheles gambiae sensu stricto (ss) mosquitoes. We investigated the potential mechanisms involved in the dhfr and dhps quintuple mutant NF-135 and the single dhps 437 mutant NF-54. Concentrations of sulfadoxine (S) and pyrimethamine (P) equivalent to the serum levels of the respective drugs on day 3 (S=61 microg/ml, P=154.7 ng/ml) day 7 (S=33.8 microg/ml, P=66.6 ng/ml) and day 14 (S=14.2 microg/ml, P=15.7 ng/ml) post-SP treatment were used to study the effect on gametocytogenesis, gametocyte maturation and infectivity to Anopheles stephensi mosquitoes fed through an artificial membrane. The drugs readily induced gametocytogenesis in the mutant NF-135 strain but effectively killed the wild-type NF-54. However, both drugs impaired gametocyte maturation yielding odd-shaped non-exflagellating mature gametocytes. The concomitant ingestion of both S and P together with gametocytemic blood-meal significantly reduced the prevalence of oocyst positivity as well as oocyst density when compared to controls (P<0.001). In addition, day 3 concentrations of SP decreased mosquito survival by up to 65% (P<0.001). This study demonstrates that SP is deleterious in vitro for gametocyte infectivity as well as mosquito survival.

School-based participatory health education for malaria control in Ghana: engaging children as health messengers

Background

School children have been increasingly recognized as health messengers for malaria control. However, little evidence is available. The objective of this study was to determine the impact of school-based malaria education intervention on school children and community adults.

Methods

This study was conducted in the Dangme-East district of the Greater Accra Region, Ghana, between 2007 and 2008. Trained schoolteachers designed participatory health education activities and led school children to disseminate messages related to malaria control to their communities. Three schools and their respective communities were chosen for the study and assigned to an intervention group (one school) and a control group (two schools). Questionnaire-based interviews and parasitological surveys were conducted before and after the intervention, with the intervention group (105 children, 250 community adults) and the control group (81 children, 133 community adults). Chi-square and Fisher's Exact tests were used to analyse differences in knowledge, practices, and parasite prevalence between pre- and post-intervention.

Results

After the intervention, the misperception that malaria has multiple causes was significantly improved, both among children and community adults. Moreover, the community adults who treated a bed net with insecticide in the past six months, increased from 21.5% to 50.0% (p < 0.001). Parasite prevalence in school children decreased from 30.9% to 10.3% (p = 0.003). These positive changes were observed only in the intervention group.

Conclusions

This study suggests that the participatory health education intervention contributed to the decreased malaria prevalence among children. It had a positive impact not only on school children, but also on community adults, through the improvement of knowledge and practices. This strategy can be applied as a complementary approach to existing malaria control strategies in West African countries where school health management systems have been strengthened.

In vitro activity of antifolate and polymorphism in dihydrofolate reductase of Plasmodium falciparum isolates from the Kenyan coast: emergence of parasites with Ile-164-Leu mutation

We have analyzed the activities of the antifolates pyrimethamine (PM), chlorcycloguanil (CCG), WR99210, trimethoprim (TMP), methotrexate (MTX), and trimetrexate (TMX) against Kenyan Plasmodium falciparum isolates adapted in vitro for long-term culture. We have also assessed the relationship between these drug activities and mutations in dihydrofolate reductase (dhfr), a domain of the gene associated with antifolate resistance. As expected, WR99210 was the most potent drug, with a median 50% inhibitory concentration (IC50) of <0.075 nM, followed by TMX, with a median IC50 of 30 nM. The median IC50 of CCG was 37.80 nM, and that of MTX was 83.60 nM. PM and TMP were the least active drugs, with median IC50s of 733.26 nM and 29,656.04 nM, respectively. We analyzed parasite dhfr genotypes by the PCR-enzyme restriction technique. No wild-type dhfr parasite was found. Twenty-four of 33 parasites were triple mutants (mutations at codons 108, 51, and 59), and only 8/33 were double mutants (mutations at codons 108 and 51 or at codons 108 and 59). IC50s were 2.1-fold (PM) and 3.6-fold (TMP) higher in triple than in double mutants, though these differences were not statistically significant. Interestingly, we have identified a parasite harboring a mutation at codon 164 (Ile-164-Leu) in addition to mutations at codons 108, 51, and 59. This quadruple mutant parasite had the highest TMP IC50 and was in the upper 10th percentile against PM and CCG. We confirmed the presence of this mutation by sequencing. Thus, TMX and MTX are potent against P. falciparum, and quadruple mutants are now emerging in Africa.