Intermittent preventive treatment for malaria in infants

Projected uptake of sulfadoxine-pyrimethamine for perennial malaria chemoprevention in children under 2 years of age in nine sub-Saharan African countries: an epidemiologically-based 5-year forecast analysis

BACKGROUND

Perennial malaria chemoprevention (PMC) with sulfadoxine-pyrimethamine (SP) is recommended for children under 2 years of age living in areas of perennial malaria transmission. Initially delivered through the Expanded Programme of Immunization (EPI), recent pilot studies explored PMC delivery via the vitamin A supplementation programme or community health workers (CHWs). Understanding SP demand across the various delivery channels is key to implementing PMC.

METHODS

A 5-year epidemiologically-based forecasting model was developed to estimate SP volumes required for nine sub-Saharan countries based on seven different scenarios considering the EPI, vitamin A or CHWs delivery channels, alone or in combination. Model inputs were secondary data sources, enhanced with information from a field survey conducted among 40 national decision-makers and 176 healthcare providers. Projected SP volumes were estimated based on expected coverage and uptake within the eligible population. The efficiency of meeting the need versus demand was calculated for each scenario. A sensitivity analysis was performed for base, low and high estimates of the coverage and uptake rates. The forecasting period was 2023 to 2027.

RESULTS

The eligible population in the study countries was estimated at 21 million children in 2023. Estimated demand in 2027 ranged from 17.8 million SP doses for EPI to 49.6 million when combining all delivery channels. These results were highly dependent on the coverage and uptake rate of each delivery channel. The sensitivity analysis showed that uncertainty around the estimates ranged from twofold (Vitamin A), to 3.4-fold (CHWs). EPI was the most efficient channel overall (53%), but the efficiency of each scenario varied by country depending on local contexts.

CONCLUSIONS

The model provides a tool to anticipate SP needs and demand for PMC under various scenarios, aiding manufacturers, donors, partners, governments, and procurement organizations in effective planning for PMC implementation.

It Is Time to Strengthen the Malaria Control Policy of the Democratic Republic of Congo and Include Schools and School-Age Children in Malaria Control Measures

Despite a decade of sustained malaria control, malaria remains a serious public health problem in the Democratic Republic of Congo (DRC). Children under five years of age and school-age children aged 5-15 years remain at high risk of symptomatic and asymptomatic malaria infections. The World Health Organization's malaria control, elimination, and eradication recommendations are still only partially implemented in DRC. For better malaria control and eventual elimination, the integration of all individuals into the national malaria control programme will strengthen malaria control and elimination strategies in the country. Thus, inclusion of schools and school-age children in DRC malaria control interventions is needed.

Intermittent screening and treatment for malaria complementary to routine immunisation in the first year of life in Papua, Indonesia: a cluster randomised superiority trial

BACKGROUND

In Papua (Indonesia), infants with P. falciparum and/or P. vivax malaria are at risk of severe anaemia and death. We hypothesized that in an area of high malaria transmission, intermittent screening and treatment of infants with malaria (ISTi) will reduce morbidity compared to passive case detection (PCDi).

METHODS

We conducted a cluster randomised, open label, superiority trial. A total of 21 clusters of village health posts (VHP) were randomised 1:1 to either IST for infants coinciding with 4 routine immunisation visits or PCDi. Healthy term infants born to consenting mothers enrolled into a maternal malaria cluster randomised trial were included in the study and followed for 12 months. Point of care malaria rapid diagnostic tests were used to detect peripheral parasitaemia at 2, 3, 4 and 9 months old in all infants in ISTi clusters and when symptomatic in PCDi clusters. Infants with detected peripheral parasitaemia were treated with dihydroartemisinin-piperaquine. The co-primary outcomes were the incidence rate of clinical malaria in the first year of life and the prevalence of parasitaemia at age 12 months. The incidence rate ratio and prevalence ratio between ISTi and PCDi were estimated using mixed-effects Poisson and log-binomial regression modelling (accounting for clustering at VHP level).

RESULTS

Between May 2014 and February 2017, 757 infants were enrolled into the study, 313 into 10 ISTi clusters, and 444 into 11 PCDi clusters. Overall, 132 episodes of parasitaemia were detected, of whom 17 (12.9%) were in symptomatic infants. Over 12 months, the incidence rate (IR) of clinical malaria was 24 [95% CI, 10-50] per 1000 children-years at risk in the ISTi arm and 19 [95% CI, 8,38] per 1000 children-years in the PCDi arm (adjusted incidence rate ratio [aIRR] 1.77 [95% CI, 0.62-5.01]; p = 0.280). The prevalence of parasitaemia at 12 months was 13% (33/254) in the IST clusters and 15% (57/379) in the PCD clusters (adjusted prevalence ratio (aPR) = 0.92 (95% CI, 0.70-1.21), p = 0.55). There was no difference in the risk of anaemia between treatment arms.

CONCLUSIONS

In high malaria transmission area outside of Africa, our study suggests that compared to PCDi, ISTi offers no significant benefit in reducing the risk of clinical malaria in infants born to women receiving effective protection from malaria during pregnancy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02001428 , registered on 20 Nov 2013.

Malaria chemoprevention and drug resistance: a review of the literature and policy implications

Chemoprevention strategies reduce malaria disease and death, but the efficacy of anti-malarial drugs used for chemoprevention is perennially threatened by drug resistance. This review examines the current impact of chemoprevention on the emergence and spread of drug resistant malaria, and the impact of drug resistance on the efficacy of each of the chemoprevention strategies currently recommended by the World Health Organization, namely, intermittent preventive treatment in pregnancy (IPTp); intermittent preventive treatment in infants (IPTi); seasonal malaria chemoprevention (SMC); and mass drug administration (MDA) for the reduction of disease burden in emergency situations. While the use of drugs to prevent malaria often results in increased prevalence of genetic mutations associated with resistance, malaria chemoprevention interventions do not inevitably lead to meaningful increases in resistance, and even high rates of resistance do not necessarily impair chemoprevention efficacy. At the same time, it can reasonably be anticipated that, over time, as drugs are widely used, resistance will generally increase and efficacy will eventually be lost. Decisions about whether, where and when chemoprevention strategies should be deployed or changed will continue to need to be made on the basis of imperfect evidence, but practical considerations such as prevalence patterns of resistance markers can help guide policy recommendations.

Economic evaluation of severe malaria in children under 14 years in Zambia

Introduction

Malaria exerts a significant economic burden on health care providers and households and our study attempts to make claims on the cost effectiveness of artesunate against quinine in patients under 14 years of age in Zambia. Also, to find the average total costs involved in the treatment of severe malaria in children and their impact on household expenditure.

Methods

Cost-effectiveness analysis of severe malaria treatment was conducted from a healthcare provider perspective using a Markov model. Standard costing was performed for the identification, measurement and assessment phases with data from quantification reports for anti-malaria commodities as these documents provides drug procurement costs from suppliers and freight costs. Average and incremental cost-effectiveness ratio were estimated and uncertainties were assessed through probabilistic sensitivity analysis.

Results

In Zambia severe malaria in children has been shown to account for over 45% of the total monthly curative healthcare costs incurred by households compared to the mean per capita monthly income. The cost of treating severe malaria depleted 7.67% of the monthly average household income. According, to the cost effectiveness analysis the of artesunate with quinine the ICER was $105 per death averted.

Conclusion

The use of artesunate over quinine in the treatment of severe malaria in children under 14 years is a highly cost-effective strategy for the healthcare provider in Zambia.

Forest malaria and prospects for anti-malarial chemoprophylaxis among forest goers: findings from a qualitative study in Lao PDR

Background

Despite significant decline in malarial incidence and mortality in countries across the Greater Mekong Subregion, the disease remains a public health challenge in the region; transmission continues mainly among people who visit forests in remote areas, often along international borders, where access to primary healthcare is limited. In the absence of effective vector-control measures and limited exposure periods, malaria chemoprophylaxis has been proposed as a strategy to protect forest goers. As a rarely used approach for indigenous populations, questions remain about its feasibility and acceptability. Drawing on in-depth interviews with forest goers and stakeholders, this article examines opportunities and challenges for implementation of anti-malarial chemoprophylaxis for forest goers in Lao PDR.

Methods

In-depth interviews were conducted with 16 forest goers and 15 stakeholders in Savannakhet province, Lao PDR. Interview topics included experience of malaria prevention and health services, and perceptions of prophylaxis as a potential component of malaria elimination strategy. The interviews were transcribed and coded using inductive and deductive approaches for qualitative thematic analysis.

Results

In ethnically and geographically diverse villages, awareness of malaria risk prompts forest goers to protect themselves, albeit sub-optimally using available preventive measures. Stakeholders highlighted challenges for targeting at-risk populations and approaches to address forest malaria in southern Lao PDR. Among policymakers, choice and cost of anti-malarials, particularly their efficacy and source of funding, were key considerations for the feasibility of malaria prophylaxis. Acceptability of prophylaxis among forest goers was also influenced by the complexity of the regimen, including the number of tablets and timing of doses. Implementation of prophylaxis may be affected by a lack of transportation and communication barriers in remote communities.

Conclusion

Adding prophylaxis to existing malaria control activities requires strengthening the capacity of local health workers in Lao PDR. Ideally, this would be part of an integrated approach that includes strategies to address the other febrile illnesses that forest goers describe as priority health concerns. The prophylactic regimen also requires careful consideration in terms of effectiveness and simplicity of dosing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-021-04027-z.

Acceptability and feasibility of malaria prophylaxis for forest goers: findings from a qualitative study in Cambodia

BACKGROUND

In the Greater Mekong Subregion, adults are at highest risk for malaria, particularly those who visit forests. The absence of effective vector control strategies and limited periods of exposure during forest visits suggest that chemoprophylaxis could be an appropriate strategy to protect forest goers against malaria.

METHODS

Alongside a clinical trial of anti-malarial chemoprophylaxis in northern Cambodia, qualitative research was conducted, including in-depth interviews and observation, to explore the acceptability of malaria prophylaxis for forest goers, the implementation opportunities, and challenges of this strategy.

RESULTS

Prophylaxis with artemether-lumefantrine for forest goers was found to be acceptable under trial conditions. Three factors played a major role: the community's awareness and perception of the effectiveness of prophylaxis, their trust in the provider, and malaria as a local health concern. The findings highlight how uptake and adherence to prophylaxis are influenced by the perceived balance between benefits and burden of anti-malarials which are modulated by the seasonality of forest visits and its influence on malaria risk.

CONCLUSIONS

The implementation of anti-malarial prophylaxis needs to consider how the preventive medication can be incorporated into existing vector-control measures, malaria testing and treatment services. The next step in the roll out of anti-malarial prophylaxis for forest visitors will require support from local health workers.

Which public health interventions are effective in reducing morbidity, mortality and health inequalities from infectious diseases amongst children in low- and middle-income countries (LMICs): An umbrella review

Despite significant progress in the last few decades, infectious diseases remain a major threat to child health in low- and middle-income countries (LMICs)-particularly amongst more disadvantaged groups. It is imperative to understand the best available evidence concerning which public health interventions reduce morbidity, mortality and health inequalities in children aged under five years. To address this gap, we carried out an umbrella review (a systematic reviews of reviews) to identify evidence on the effects of public health interventions (promotion, protection, prevention) on morbidity, mortality and/or health inequalities due to infectious diseases amongst children in LMICs. Ten databases were searched for records published between 2014-2021 alongside a manual search of gray literature. Articles were quality-assessed using the Assessment of Multiple Systematic Reviews tool (AMSTAR 2). A narrative synthesis was conducted. We identified 60 systematic reviews synthesizing 453 individual primary studies. A majority of the reviews reported on preventive interventions (n = 48), with a minority on promotion (n = 17) and almost no reviews covering health protection interventions (n = 2). Effective interventions for improving child health across the whole population, as well as the most disadvantaged included communication, education and social mobilization for specific preventive services or tools, such as immunization or bed nets. For all other interventions, the effects were either unclear, unknown or detrimental, either at the overall population level or regarding health inequalities. We found few reviews reporting health inequalities information and the quality of the evidence base was generally low. Our umbrella review identified some prevention interventions that might be useful in reducing under five mortality from infectious diseases in LMICs, particularly amongst the most disadvantaged groups.

Perception of Malaria Chemoprevention Interventions in Infants and Children in Eight Sub-Saharan African Countries: An End User Perspective Study

Preventive chemotherapy interventions have been identified as key tools for malaria prevention and control. Although a large number of publications have reported on the efficacy and safety profile of these interventions, little literature exists on end-user experience. The objective of this study was to provide insights on the perceptions and attitudes towards seasonal malaria chemoprevention (SMC) and intermittent preventive treatment of infants (IPTi) to identify drivers of and barriers to acceptance. A total of 179 in-depth qualitative interviews were conducted with community health workers (CHWs), health center managers, parents of children receiving chemoprevention, and national decision makers across eight countries in sub-Saharan Africa. The transcribed verbatim responses were coded and analyzed using a thematic approach. Findings indicate that, although SMC is largely accepted by end users, coverage remained below 100%. The main causes mentioned were children's absenteeism, children being sick, parents' reluctance, and lack of staff. Regarding IPTi, results from participants based in Sierra Leone showed that the intervention was generally accepted and perceived as efficacious. The main challenges were access to water, crushing the tablets, and high staff turnover. SMC and IPTi are perceived as valuable interventions. Our study identified the key elements that need to be considered to facilitate the expansion of these two interventions to different geographies or age groups.

Antimalarial Drug Resistance and Implications for the WHO Global Technical Strategy

PURPOSE OF REVIEW

Five years have passed since the World Health Organization released its Global Technical Strategy for Malaria (GTS). In that time, progress against malaria has plateaued. This review focuses on the implications of antimalarial drug resistance for the GTS and how interim progress in parasite genomics and antimalarial pharmacology offer a bulwark against it.

RECENT FINDINGS

For the first time, drug resistance-conferring genes have been identified and validated before their global expansion in malaria parasite populations. More efficient methods for their detection and elaboration have been developed, although low-density infections and polyclonality remain a nuisance to be solved. Clinical trials of alternative regimens for multidrug-resistant malaria have delivered promising results. New agents continue down the development pipeline, while a nascent infrastructure in sub-Saharan Africa for conducting phase I trials and trials of transmission-blocking agents has come to fruition after years of preparation.

SUMMARY

These and other developments can help inform the GTS as the world looks ahead to the next two decades of its implementation. To remain ahead of the threat that drug resistance poses, wider application of genomic-based surveillance and optimization of existing and forthcoming antimalarial drugs are essential.

Evaluation of health system readiness and coverage of intermittent preventive treatment of malaria in infants (IPTi) in Kambia district to inform national scale-up in Sierra Leone

BACKGROUND

Intermittent preventive treatment of malaria in infants (IPTi) with sulfadoxine-pyrimethamine (SP) is a proven strategy to protect infants against malaria. Sierra Leone is the first country to implement IPTi nationwide. IPTi implementation was evaluated in Kambia, one of two initial pilot districts, to assess quality and coverage of IPTi services.

METHODS

This mixed-methods evaluation had two phases, conducted 3 (phase 1) and 15-17 months (phase 2) after IPTi implementation. Methods included: assessments of 18 health facilities (HF), including register data abstraction (phases 1 and 2); a knowledge, attitudes and practices survey with 20 health workers (HWs) in phase 1; second-generation sequencing of SP resistance markers (pre-IPTi and phase 2); and a cluster-sample household survey among caregivers of children aged 3-15 months (phase 2). IPTi and vaccination coverage from the household survey were calculated from child health cards and maternal recall and weighted for the complex sampling design. Interrupted time series analysis using a Poisson regression model was used to assess changes in malaria cases at HF before and after IPTi implementation.

RESULTS

Most HWs (19/20) interviewed had been trained on IPTi; 16/19 reported feeling well prepared to administer it. Nearly all HFs (17/18 in phase 1; 18/18 in phase 2) had SP for IPTi in stock. The proportion of parasite alleles with dhps K540E mutations increased but remained below the 50% WHO-recommended threshold for IPTi (4.1% pre-IPTi [95%CI 2-7%]; 11% post-IPTi [95%CI 8-15%], p < 0.01). From the household survey, 299/459 (67.4%) children ≥ 10 weeks old received the first dose of IPTi (versus 80.4% for second pentavalent vaccine, given simultaneously); 274/444 (62.5%) children ≥ 14 weeks old received the second IPTi dose (versus 65.4% for third pentavalent vaccine); and 83/217 (36.4%) children ≥ 9 months old received the third IPTi dose (versus 52.2% for first measles vaccine dose). HF register data indicated no change in confirmed malaria cases among infants after IPTi implementation.

CONCLUSIONS

Kambia district was able to scale up IPTi swiftly and provide necessary health systems support. The gaps between IPTi and childhood vaccine coverage need to be further investigated and addressed to optimize the success of the national IPTi programme.