Rethinking integrated service delivery for malaria

Computational identification of aspartic protease inhibitors for antimalarial drug development against Plasmodium Vivax

Malaria is a parasitic disease that has caused suffering to humans since ancient times and remains a major public health concern in tropical and subtropical regions.The development of novel antimalarials therefore becomes of utmost importance by targeting aspartic protease. The computational study utilized a molecular docking approach to identify hit compounds. In this stuyda molecular docking approach was employed to identify potential hit compounds. The molecular docking analysis yielded three hit compounds CMNPD229, ZINC000000018635, and ZINC000005425464 along with the reference drug chloroquine, with binding energy scores of -8.1 kcal/mol, -8.0 kcal/mol, -7.8 kcal/mol, and - 6.8 kcal/mol, respectively. These compounds were further to assess their potential as optimal drug candidates. Subsequently density function theory (DFT) was performed. Afterward, the protein-ligand (PL) complexes were subjected to molecular dynamic simulation (MDS) to identify the stability and rigidity of the complexes in a fleeting and dynamic setting. The complex CMNPD229 exhibited good stability followed by ZINC000000018635, ZINC000005425464, and the Control. The compounds showed good MM-PBSA/GBSA, WaterSwap, and entropy energy values. The calculated MM-PBSA/GBSA binding free energy scores were - 120.78 kcal/mol, -107.16 kcal/mol, -91.00 kcal/mol, and - 97.49 kcal/mol for CMNPD229, ZINC000000018635, ZINC000005425464, and the reference drug, respectively.Additionally, salt bridge analysis and secondary structure evaluation revealed that CMNPD229 formed the highest number of interactions (Glu290-Arg23 and Glu305-Lys306), indicating its stability as a potential drug candidate. This study suggests that CMNPD229 holds promise as a potent antimalarial drug by effectively inhibiting Plasmodium falciparum and Plasmodium vivax aspartic proteases.

Situational analysis of malaria in Cabo Verde: From endemic control to elimination, history, cases data and challenges ahead

On 12 January 2024, Cabo Verde was officially certified by the WHO as a malaria-free country after six consecutive years without local transmission. This study analysed the malaria history of Cabo Verde from 1953 to certification in 2024, highlighted the valuable lessons learned, and discussed challenges for prevention reintroduction. Malaria data from the last 35 years (1988-2022) were analysed using descriptive analyses, and cases were mapped using the USGS National Map Viewer. From 1988 to 2022, 3,089 malaria cases were reported, 2.381 (77.1%) locally and 708 (22.9%) imported. Imported cases were reported nationwide except on Brava Island. Six municipalities did not report any cases, while local cases were restricted to Santiago and Boavista, with 2.360 and 21 cases, respectively. Malaria history in the country revealed six remarkable steps and three periods of interruption in the transmission of local malaria cases. The last local cases were reported in Boavista in 2015 and Santiago in 2017. Since 2018, introduced cases have been recorded from time to time. Disease lethality was low, with ten malaria deaths from 2010 to 2023, and the highest value of 8.3% (3/36) recorded in 2011. With this certification, Cabo Verde became a reference in Africa for its health sector organisation, multisectoral, and partnership in malaria control. However, maintaining the certification presents several sustainability challenges for the country. Additionally, robust epidemiological and entomological surveillance, continued investigations, and ongoing research are crucial.

Systematic review on the cost of seasonal malaria chemoprevention (SMC)

BACKGROUND

Implemented in 17 countries to date, seasonal malaria chemoprevention (SMC) is a recommended strategy to prevent childhood malaria in areas with seasonal transmission of P. falciparum through monthly administration of antimalarial medicines. Understanding the costs and resource requirements of SMC delivery is necessary for effective planning and resource allocation. This systematic literature review aims to assess the evidence on the cost and cost-effectiveness of SMC delivery.

METHODS

Following PRISMA guidelines, five databases were systematically reviewed to identify evidence on SMC costs and cost-effectiveness published between 2012 and 2023. Studies with defined costing methodologies and cost output measures were included, excluding those relying solely on mathematical modeling. Two reviewers assessed each study for eligibility and extracted cost data, which were adjusted for inflation. Quality assessment was completed using the CHEERS checklist.

RESULTS

Six costing studies were identified spanning nine countries. Four studies examined costs during an SMC pilot or introduction, one during scale-up, and one costed newly established SMC campaigns through a multi-country project. Costs were examined at country level with the financial costs per child receiving a full course of SMC ranging from $1.71 to $12.46, while economic costs per child ranged from $2.11 to $29.06. Four studies included a cost effectiveness analysis with incremental cost-effectiveness ratios (ICERs) per clinical malaria case averted ranging from $5.41 to $138.03; ICER per disability-adjusted life year (DALY) averted from $24.51 to $182.88; and ICER per death averted from $688.86 to $18,418.81. Differences in cost estimates stemmed from different factors including variations in cost ingredients, scale of the intervention, and study perspectives.

DISCUSSION

The level of detail for reporting SMC costs and cost categories varied greatly by study as did the scale of intervention, limiting comparability as well as an understanding of the complete costs and resource requirements for SMC implementation. Cost evidence is not from mature programs but from pilots or relatively new campaigns. Costs incurred by households and costs of the integrated delivery of SMC with other health interventions were often overlooked. Adopting a standardized costing approach for mature SMC programmes could provide a better understanding of resource requirements and costs while enhancing study comparability across settings, better informing future resource allocation and improving efficiency.

Waning success: a 2013-2022 spatial and temporal trend analysis of malaria in Ethiopia

BACKGROUND

Despite consecutive decades of success in reducing malaria transmission, Ethiopia went off track towards its goal of malaria elimination by 2030, as outlined in the NMCP malaria strategy. Recent malaria outbreaks in Ethiopia are attributed to the emergence and spread of diagnostic and drug-resistant Plasmodium falciparum, increased insecticide resistance in major vectors and the spread of invasive Anopheles stephensi. The effects of the COVID-19 pandemic, environmental anomalies and internal conflicts have also potentially played a role in increasing malaria transmission. This study aimed to evaluate the contribution of environmental factors and An. stephensi to the spatiotemporal trends of recent malaria cases in Ethiopia.

METHODS

Clinical malaria case data reported weekly between January 2013 and January 2023 were obtained from the Ethiopian Public Health Institute (EPHI), Addis Ababa. A negative binomial regression model was used to explain the variability and potential overdispersion in the weekly number of malaria cases reported across Ethiopian administrative zones. This model incorporated fixed effects for selected environmental factors and random effects to capture temporal trends, zone specific seasonal patterns, spatial trends at the zone level, and the presence of An. stephensi and its impact.

RESULTS

Our negative binomial regression model highlighted 56% variability in the data and slightly more than half (55%) was due to environmental factors, while the remainder was captured by random effects. A significant nationwide decline in malaria risk was observed between 2013 and 2018, followed by a sharp increase in early 2022. Malaria risk was higher in western and northwestern zones of Ethiopia compared to other zones. Zone-specific seasonal patterns, not explained by environmental factors, were grouped into four clusters of seasonal behaviours. The presence of An. stephensi was not shown to have any significant impact on malaria risk.

CONCLUSIONS

Understanding the spatial and temporal drivers of malaria transmission and therefore identifying more appropriate malaria control strategies are key to the success of any malaria elimination and eradication programmes in Ethiopia. Our study found that approximately 50% of malaria risk variability could be explained by environmental, temporal, and spatial factors included in the analysis, while the remaining variation was unexplained and may stem from other factors not considered in this study. This highlights the need for a better understanding of underlying factors driving local malaria transmission and outbreaks, to better tailor regional programmatic responses.

Malaria treatment for prevention: a modelling study of the impact of routine case management on malaria prevalence and burden

BACKGROUND

Testing and treating symptomatic malaria cases is crucial for case management, but it may also prevent future illness by reducing mean infection duration. Measuring the impact of effective treatment on burden and transmission via field studies or routine surveillance systems is difficult and potentially unethical. This project uses mathematical modeling to explore how increasing treatment of symptomatic cases impacts malaria prevalence and incidence.

METHODS

Leveraging the OpenMalaria stochastic agent-based transmission model, we first simulated an array of transmission intensities with baseline effective treatment coverages of 28%, 44%, and 54% incorporated to reflect the 2023 coverage distribution across Africa, as estimated by the Malaria Atlas Project. We assessed the impact of increasing coverage to as high as 60%, the highest 2023 estimate on the continent. Subsequently, we performed simulations resembling the specific subnational endemicities of Kenya, Mozambique, and Benin, using the Malaria Atlas Project estimates of intervention coverages to reproduce historical subnational prevalence. We estimated the impact of increasing effective treatment coverage in these example settings in terms of prevalence reduction and clinical cases averted in children under 5 years old and the total population.

RESULTS

The most significant prevalence reduction - up to 50% - was observed in young children from lower transmission settings (prevalence below 0.2), alongside a 35% reduction in incidence, when increasing effective treatment from 28% to 60%. A nonlinear relationship between baseline transmission intensity and the impact of treatment was observed. Increasing effective treatment coverage to 60% reduced the risk in high-risk areas (prevalence in children under 5 years old > 0.3), affecting 39% of young children in Benin and 20% in Mozambique previously living in those areas. In Kenya where most of the population lives in areas with prevalence below 0.15, and case management is fairly high (53.9%), 0.39% of children were estimated to transition to lower-risk areas.

CONCLUSIONS

Improving case management directly reduces the burden of illness, but these results suggest it also reduces transmission, especially for young children. With vector control interventions, enhancing case management can be an important tool for reducing transmission intensity over time.

Community engagement in mobile and hard-to-reach populations: a community-based intervention for malaria elimination in a tri-national region of the Guiana Shield

Several countries of the Guiana Shield are aiming at the control and elimination of malaria in areas where Artisanal and Small-scale Gold Mining (ASGM) activities predominate, raising questions about how to strengthen community engagement to improve the effectiveness of health programs. The Curema project focuses its intervention on the mobile and hard-to-reach ASGM population, complementing the efforts of national programs in the Guiana Shield. The Curema intervention combines targeted drug administration for suspected Plasmodium vivax asymptomatic carriers, the Malakit distribution, and health education activities. The primary goals of this manuscript are to outline a pathway to foster community participation in the Curema project aimed at eliminating malaria. Thus, it presents a vision of the challenges that the AGSM community poses in terms of community participation for an asymptomatic problem; and highlights the community-based model and the Information, Education and Communication (IEC) components as foundations for participation. In addition, it also presents culturally sensitive IEC strategies designed through iterative and collaborative consultative processes and other bottom-up outreach activities. The community engagement approach facilitates adaptability and responsiveness in a complex, evolving context increasing the effectiveness of interventions.

Identifying and characterizing high-risk populations in pilot malaria elimination districts in Madagascar: a mixed-methods study

BACKGROUND

In Madagascar, the districts of Antsirabe II, Faratsiho and Antsiranana I have relatively low malaria incidence rates and have been selected by the National Malaria Control Programme for pilot elimination strategies. The districts have residual transmission despite increasing coverage and quality of malaria services. This study sought to identify priority subpopulations at highest risk for malaria and collect information on intervention preferences and methods that will inform subnational tailoring of malaria service delivery.

METHODS

This mixed methods study employed (i) a quantitative malaria risk factor assessment in Antsirabe II and Faratsiho comprising a test-negative frequency matched case-control study and a qualitative risk factor assessment in Antsiranana I; and (ii) a qualitative formative assessment in all three districts. For the case-control study, a mixed effects logistic regression was used with age, sex and district included as fixed effects and health facility included as a random effect. The qualitative risk factor assessment used semi-structured interview guides and key informant interviews. For the qualitative formative assessment in the three districts, a summary report was generated following semi-structured interviews and focus group discussions with high-risk populations (HRPs) and stakeholders.

RESULTS

In Antsirabe II and Faratsiho districts, rice agriculture workers, outdoor/manual workers, particularly miners, and those with jobs that required travel or overnight stays, especially itinerant vendors, had higher odds of malaria infection compared to other (non-rice) agricultural workers. In Antsiranana I, respondents identified non-rice farmers, mobile vendors, and students as HRPs. Risk factors among these groups included overnight stays and travel patterns combined with a lack of malaria prevention tools. HRPs reported treatment cost and distance to the health facility as barriers to care and expressed interest in presumptive treatment and involvement of gatekeepers or people who have influence over intervention access or participation.

CONCLUSIONS

The study results illustrate the value of in-depth assessments of risk behaviours, access to services and prevention tools, surveillance and prevention strategies, and the involvement of gatekeepers in shaping subnational tailoring to reach previously unreached populations and address residual transmission in elimination settings.

Defining operational research priorities to improve malaria control and elimination in sub-Saharan Africa: results from a country-driven research prioritization setting process

BACKGROUND

In order to reignite gains and accelerate progress toward improved malaria control and elimination, policy, strategy, and operational decisions should be derived from high-quality evidence. The U.S. President's Malaria Initiative (PMI) Insights project together with the Université Cheikh Anta Diop of Dakar, Senegal, conducted a broad stakeholder consultation process to identify pressing evidence gaps in malaria control and elimination across sub-Saharan Africa (SSA), and developed a priority list of country-driven malaria operational research (OR) and programme evaluation (PE) topics to address these gaps.

METHODS

Five key stakeholder groups were engaged in the process: national malaria programmes (NMPs), research institutions in SSA, World Health Organization (WHO) representatives in SSA, international funding agencies, and global technical partners who support malaria programme implementation and research. Stakeholders were engaged through individual or small group interviews and an online survey, and asked about key operational challenges faced by NMPs, pressing evidence gaps in current strategy and implementation guidance, and priority OR and PE questions to address the challenges and gaps.

RESULTS

Altogether, 47 interviews were conducted with 82 individuals, and through the online survey, input was provided by 46 global technical partners. A total of 33 emergent OR and PE topics were identified through the consultation process and were subsequently evaluated and prioritized by an external evaluation committee of experts from NMPs, research institutions, and the WHO. The resulting prioritized OR and PE topics predominantly focused on generating evidence needed to close gaps in intervention coverage, address persistent challenges faced by NMPs in the implementation of core strategic interventions, and inform the effective deployment of new tools.

CONCLUSION

The prioritized research list is intended to serve as a key resource for informing OR and PE investments, thereby ensuring future investments focus on generating the evidence needed to strengthen national strategies and programme implementation and facilitating a more coordinated and impactful approach to malaria operational research.

Malaria among the elderly in five communities of Osun East district, Southwest Nigeria: Prevalence and association with non-communicable diseases

Objective:

The level of immunity against pathogens decreases with old age. As a result, the elderly may be regarded to be at increased risk of malaria morbidity and fatality. There is paucity of studies on malaria among the elderly population in Osun East district, Southwest Nigeria. This study aimed to determine the prevalence of malaria and its association with medical comorbidities among the elderly.

Methods:

A descriptive cross-sectional study was carried out, which involved 972 adult residents of five communities in Osun State, who were selected using a multistage random sampling technique. Data was collected with aid of a structured questionnaire. The medical history of respondents and anthropometric measures were obtained. The presence of malaria parasitaemia in the respondents was determined by rapid diagnostic test (RDT). Appropriate descriptive and inferential analyses were done.

Results:

Out of the 972 respondents, 504 (51.9%) were 60 years and above. The overall prevalence of malaria RDT positivity was 4%. The positivity rate was higher among the elderly (4.6%) compared to those less than 60 years (3.4%), albeit not statistically significant ( p = 0.36). Among these elderlies, 52.6% and 16.1% used insecticide-treated nets and insecticide sprays, respectively. There was no association between the prevalence of malaria positivity and comorbid conditions, such as hypertension ( p = 0.37), overweight/obesity ( p = 0.77), or diabetes ( p = 0.15). Malaria positivity rate was also not significantly associated with the use of insecticide-treated nets ( p = 0.64) or insecticide sprays ( p = 0.45).

Conclusion:

The malaria positivity rate was higher among the elderly in the study area, although not statistically significant. The prevalence was not associated with comorbid medical conditions.