What sub-Saharan African countries can learn from malaria elimination in China

A retrospective analysis of the malaria trend in Yemen over the sixteen-years, from 2006 to 2021

BACKGROUND

Malaria is one of the important diseases that threatens the global health system, especially in developing countries, including Yemen. Based on surveillance data, this analysis aimed to assess the trend of malaria in Yemen over the last sixteen years from 2006 to 2021.

METHODS

A retrospective analysis was conducted on secondary malaria data from the database from the Ministry of Public Health and Population in Yemen.

RESULTS

Of the 15,153,763 suspected cases, approximately 3,651,508 malaria cases were confirmed by both laboratory and clinical diagnoses. Plasmodium falciparum, P. vivax, mixed infections, P. malariae, and P. ovale were recorded at 1,118,117 (98.72%), 123,28 (1.10%), 1838 (0.16%), 155 (0.01%), and 30 (0.01%), respectively. Approximately 77.2% of all malaria cases were recorded in six governorates. Al Hudaydah recorded the highest number of malaria cases (1,231,294), followed by Hajjah (623,937), Taiz (450,051), Dhamar (167,399), Sa'adah (157,881), and Al-Mahweet (154,763). The overall incidence rate of malaria cases and P. falciparum, respectively, was 8.9 and 2.66 per 1,000 people. The highest mean incidence rate of malaria was recorded in Al Hudaydah, Hajjah, Al-Mahweet, Sa'adah, and Abyan, respectively, at 29.71, 19.49, 14.98, 10.62, and 10.14 per 1,000 people. Yemen reported 704 (0.02%) malaria death cases with an overall rate of case fatality of 0.03% and a mortality rate of 0.18 per 100,000 populations. The trend of case fatality decreased from 0.029% in 2006 to 0.015% in 2020, while the mortality rate per 100,000 individuals decreased from 0.3 in 2006 to 0.08 in 2021.

CONCLUSION

It currently suggests a continuous increase in the malaria burden without specifying trends or fluctuations and is becoming a public health threat and causing widespread concern. Therefore, the treatment and prevention of malaria infection are crucial for reducing mortality and complications by increasing the use of vector control tools and promoting early diagnosis and treatment.

Preserving nets, protecting children: an evaluation of factors influencing the utilization and physical integrity of long-lasting insecticidal nets among under-five children in Osun State, Nigeria

BACKGROUND

Malaria remains a significant public health challenge in Africa where it is the most important vector-borne disease. Nigeria bears the largest burden, with pregnant women and children under 5 years being more affected. Although, long lasting insecticidal nets (LLINs) remain effective for control, its use has been suboptimal. Hence this study assessed, household ownership, physical integrity and use of LLINs among children.

METHODS

A community-based, cross-sectional study was carried out among 1642 households using a multistage sampling technique in Osun State, Nigeria. A pretested, interviewer-administered questionnaire was used to obtain information on socio-demographic characteristics and use among under-fives. LLINs were inspected for physical integrity and cleanliness. A binary logistic regression analysis was conducted to identify factors influencing LLIN use by under-fives.

RESULTS

The mean age of children was 32.2 ± 16.5 months. Most households, 1586 (96.6%) had an LLIN while 165 (10.4%) did not hang their net. Holes were present in LLINs in 360 (22.7%) households and 196 (12.4%) had dusty or stained nets. Most households, (1259; 79.4%), had at least one LLIN for every 2 household members and survey participants reported that 1331 (83.9%) under-fives slept under an LLIN the night before the survey. Factors associated with reported LLIN use were; older parents/guardians aged 50-59 years (AOR: 3.02; 95% CI 1.50-6.09), having a post-secondary education (AOR: 2.56; 95% CI 1.31-5.00), having LLIN obtained < 12 months (AOR: 4.27; 95% CI 2.39-7.64), households with one LLIN for every 2 members (AOR: 1.65; 95% CI 1.15-2.37) and households with clean nets (AOR 2.75; 95% CI 1.89-4.00) had increased odds of reported LLIN utilization by under-five children.

CONCLUSION

Although LLIN ownership and reported use were high in this study, gaps exist between ownership and reported use of LLINs. About one-fourth of LLINs had poor physical integrity. To maximize LLIN effectiveness in households, it is important to ensure the continued free distribution of nets and emphasize messages to parents/guardians on proper care, maintenance, and use of nets.

A study on the effectiveness of (+)-usnic acid as oral toxic sugar bait against adult male and female Anopheles gambiae

BACKGROUND

Despite the application of various tools for the control of vectors of Plasmodium falciparum, malaria remains the major killer disease in sub-Saharan Africa accounting for up to 90% of deaths due to the disease. Due to limitations of the useage of chemical insecticides such as resistance, negative impact on the environment and to nontarget organisms, the World Health Organization (WHO) requires that affected countries find alternative vector control tools. This study evaluated the effectiveness of ( +)-usnic acid (UA) as an insecticide through oral administration to male and female Anopheles gambiae as an alternative or additional active ingredient to be used in toxic sugar bait.

METHODS

( +)-usnic acid was diluted using acetone at 5, 10, and 15 mg/ml concentrations in three replicates. A 5 ml mixture of 2% food dye and 10% sugar using chlorine-free water mixed with the dilutions of the ( +)-usnic acid and negative control was made containing 2% food dye and 10% sugar solution. The preparations were soaked on a ball of cotton wool and placed over the net of a cup. 5 male and 5 non-blood-fed female newly hatched starved An. gambiae Kisumu strain were introduced together into a cup and monitored for knockdown and mortalities after 4, 24 48, and 72 h. The data were analysed using a multiple linear regression model using the lm function, a base R function and a posthoc test were conducted on the significant main effects and interaction terms using the emmeans function from the emmeans R package. All analyses were performed in RStudio using base R (version 4.3.3).

RESULTS

There was high mortality of both male and female An. gambiae after ingestion of the toxic sugar bait. 15 mg/ml usnic acid caused the highest mortality (50%) within the first 4 h compared to 5 and 10 mg/ml ( +)-UA. There was a decline in the mortality rate with increased exposure time from 24 to 72 h, however, there was a significant difference in mortality at 5, 10 and 15 mg/ml. Acute toxicity was associated with ingestion of 15 mg/ml after 24 h. 72 h post-mortality was lower in all concentrations than in the control. High mortality was observed among females over the first 4 h (60%) compared to males (40%) due to higher feeding rate of the toxic agent. The proportion of dead males and females was equal after 24 h while after 48 h, the proportion of dead males was high.There was a significantly lower mortality rate after 72 h for both males and females (0 to 13.3%). Compared to all the treatments, high mortality of males was observed.

CONCLUSIONS

The results of this study indicate that ( +)-UA when administered as oral sugar bait to An. gambiae has insecticidal properties and is a suitable ingredient to be used as a toxic agent in the novel attractive toxic sugar bait for the control of malaria vectors. ( +)-UA may be an alternative active ingredient as toxic bait in the effort to reduce and eliminate the transmission of Plasmodium falciparum in Africa.

Establishment and evaluation of a qPCR method for the detection of pfmdr1 mutations in Plasmodium falciparum, the causal agent of fatal malaria

Drug resistance surveillance is a major integral part of malaria control programs. Molecular methods play a pivotal role in drug resistance detection and related molecular research. This study aimed to develop a rapid and accurate detection method for drug resistance of Plasmodium falciparum (P. falciparum). A quantitative real-time PCR (qPCR) assay has been developed that identifies the mutation at locus A256T in the P.falciparum multi-drug resistance(pfmdr1) gene producing amino acid change at position 86. The results of 198 samples detected by qPCR were consistent with nested PCR and sequencing, giving an accuracy of 94.3%. The sensitivity, specificity, positive and negative predictive value of qPCR were 85.7%, 97.6%, 90.0% and 96.4%, respectively. The results of qPCR are basically consistent with the nested PCR, which is expected to replace the nested PCR as a new molecular biological method for drug resistance detection, providing reliable technical support for global malaria prevention and control.

Key contributors to malaria elimination in the People's Republic of China: a scoping review

Malaria continues to cause high levels of morbidity and mortality despite concerted efforts to control the disease. The global burden is predominantly shouldered by countries in which the disease is highly endemic. In juxtaposition, the majority of evidence on progress towards malaria elimination has been documented in countries where baseline transmission was low. A notable exception is the People's Republic of China, in which the last indigenous case of malaria was recorded in 2016 after reporting over 30 million cases across various transmission strata in 1949. This review examined the extent, range, and nature of the literature addressing key contributors to malaria elimination in China. PubMed, Embase, Web of Science, ProQuest, Google Scholar and the WHO website were searched for relevant articles, and the JBI guidelines were followed for evidence selection, data extraction, and presentation of findings. The 17 articles that satisfied the eligibility criteria demonstrated the centrality of high-level political commitment in the elimination of malaria in China. The national malaria strategy was regularly updated to reflect evolving priorities, and the health system building blocks were strengthened to meet strategic targets. A whole-of-society approach to malaria was adopted, with intersectoral, interprovincial, regional, international, and community-mobilizing collaboration mechanisms established. Collaboration with academic institutions resulted in advantageous discoveries such as artemisinin, the current global gold standard for the treatment of malaria. The impact of malaria-specific interventions was augmented by China's economic growth. The findings of the review highlight the importance of adopting a comprehensive approach to malaria control that addresses the structural determinants of ill-health alongside downstream interventions.

Lingering challenges in malaria elimination efforts in sub-Saharan Africa: Insights and potential solutions

Introduction

Between 2000 and 2015, significant gains were recorded in reducing the global burden of malaria due to enhanced global collaboration and increased funding. However, progress has stagnated post-2015, and the COVID-19 pandemic seems to have reversed some of these gains, necessitating a critical reevaluation of interventions. This paper aims to analyze the setbacks and offer recommendations for advancement in malaria control and prevention in sub-Saharan Africa.

Methods

We conducted searches on Google Scholar, PubMed, and relevant organization websites to identify relevant studies on malaria control and prevention and associated challenges in sub-Saharan Africa from 2015 to the present. Additionally, studies on individual sub-Saharan African countries were reviewed to ensure comprehensiveness. Data from selected studies were extracted and analyzed using a narrative synthesis approach to offer a concise overview of the evidence.

Findings

We observe that the halt in progress of malaria control in sub-Saharan Africa has deep roots in socioeconomic, political, and environmental factors. These challenges are exacerbated by the population explosion in the region, low coverage of interventions due to funding deficits and incessant crises, and the degradation of the efficacy of existing malaria commodities.

Conclusion

Sub-Saharan Africa is at a crossroads in its fight against malaria. Promising new frontiers such as malaria vaccines, preventive monoclonal antibodies, new-generation insecticide-treated nets, and potentially artificial intelligence-driven technologies offer hope in advancing malaria control and prevention in the region. Through commitment and collaboration, leveraging these opportunities can help surmount challenges and ultimately eliminate malaria in sub-Saharan Africa.

Therapeutic efficacy of generic artemether-lumefantrine in the treatment of uncomplicated malaria in Ghana: assessing anti-malarial efficacy amidst pharmacogenetic variations

BACKGROUND

Despite efforts made to reduce morbidity and mortality associated with malaria, especially in sub-Saharan Africa, malaria continues to be a public health concern that requires innovative efforts to reach the WHO-set zero malaria agenda. Among the innovations is the use of artemisinin-based combination therapy (ACT) that is effective against Plasmodium falciparum. Generic artemether-lumefantrine (AL) is used to treat uncomplicated malaria after appropriate diagnosis. AL is metabolized by the cytochrome P450 family of enzymes, such as CYP2B6, CYP3A4 and CYP3A5, which can be under pharmacogenetic influence. Pharmacogenetics affecting AL metabolism, significantly influence the overall anti-malarial activity leading to variable therapeutic efficacy. This study focused on generic AL drugs used in malarial treatment as prescribed at health facilities and evaluated pharmacogenomic influences on their efficacy.

METHODS

Patients who have been diagnosed with malaria and confirmed through RDT and microscopy were recruited in this study. Blood samples were taken on days 1, 2, 3 and 7 for parasite count and blood levels of lumefantrine, artemisinin, desbutyl-lumefantrine (DBL), and dihydroartemisinin (DHA), the active metabolites of lumefantrine and artemether, respectively, were analysed using established methods. Pharmacogene variation analysis was undertaken using iPLEX microarray and PCR-RFLP.

RESULTS

A total of 52 patients completed the study. Median parasite density from day 1 to 7 ranged from 0-2666/μL of blood, with days 3 and 7 recording 0 parasite density. Highest median plasma concentration for lumefantrine and desbutyl lumefantrine, which are the long-acting components of artemisinin-based combinations, was 4123.75 ng/mL and 35.87 ng/mL, respectively. Day 7 plasma lumefantrine concentration across all generic ACT brands was ≥ 200 ng/mL which potentially accounted for the parasitaemia profile observed. Monomorphism was observed for CYP3A4 variants, while there were observed variations in CYP2B6 and CYP3A5 alleles. Among the CYP3A5 genotypes, significant differences in genotypes and plasma concentration for DBL were seen on day 3 between 1/*1 versus *1/*6 (p = 0.002), *1/*3 versus *1/*6 (p = 0.006) and *1/*7 versus *1/*6 (p = 0.008). Day 7 plasma DBL concentrations showed a significant difference between *1/*6 and *1/*3 (p = 0.026) expressors.

CONCLUSIONS

The study findings show that CYP2B6 and CYP3A5 pharmacogenetic variations may lead to higher plasma exposure of AL metabolites.

The Malaria Burden: A South African Perspective

Malaria is a deadly disease caused by protozoan pathogens of the Plasmodium parasite. Transmission to humans occurs through the bite of an infected female Anopheles mosquito. According to the World Health Organization (WHO), an estimated 247 million cases of malaria were recorded worldwide in 2021, with approximately 619 000 malaria deaths. The initial signs of malaria can be mild and challenging to diagnose due to the signs and symptoms being similar to those of other illnesses. The malaria burden remains largely concentrated in the WHO sub-Saharan African region and has been recognised as a significant contributor to morbidity and mortality. This review aims to contribute to the existing knowledge on malaria in South Africa, a region within sub-Saharan Africa, focusing on the epidemiology and life cycle of the malaria parasite as well as diagnostic approaches for detecting malaria. In addition, nonpharmacological and pharmacological interventions for treating and preventing malaria infections will also be discussed herein. While there has been a significant reduction in the global burden of this disease, malaria remains a public health issue in South Africa. As such, the implementation of effective preventative measures and strategies, early diagnosis, and appropriate treatment regimens are crucial to reducing the malaria burden in South Africa.

Trend analysis of malaria surveillance data in West Wallaga, West Oromia, Ethiopia: a framework for planning and elimination

BACKGROUND

Although Ethiopia has made a remarkable progress towards malaria prevention and control, malaria remains one of the most devastating parasitic diseases affecting humans. However, the distribution and transmission of malaria varies across the country. The study aimed to describe 5 years of malaria distribution and magnitude within the West Wallaga Zone and its respective woredas.

METHODS

A retrospective cross-sectional study design was conducted from April 10, 2019 to May 2019. Surveillance data collected weekly for a 5-year (2014-2018) from health facilities and private clinics that were archived in zonal PHEM database were reviewed. The checklist contained variety of variables was developed to collect data. Descriptive analysis was conducted to determine the proportion of Plasmodium species, positivity rate, mortality and fatality rate, time trend, and admission status; and presented by text, tables and figures.

RESULTS

Of the total of 588,119 suspected malaria cases, 78,658 (43/1000 populations) were positive with average positivity rate of 13.4%. Among confirmed cases, 59,794 (75%) of cases were attributed to Plasmodium falciparum, 16,518 (20%) were Plasmodium vivax, and 2,360 (5%) were mixed infections. The maximum (145,091) and minimum (74,420) transmissions were reported in 2014 and 2018, respectively. There was seasonal variation in transmission; spring (from May to July) and also autumn seasons (from October to November) were found as malaria transmission peaks. Although incidence rate declined throughout the study period, the average annual incidence rate was 14.38 per 1000 populations. The average case fatality rate of 5 consecutive years was 12/78,658 (15/100,000) population.

CONCLUSION

Although the malaria prevalence was decreased, the mortality due to malaria was increased in the 5-year study period, and malaria is still among the major public health problems. The dominant species of malaria parasites were P. falciparum and P. vivax. Attention is needed in scaling-up vector control tools in high malaria transmission periods.

A. Pienaah C, Luginaah I. Child malaria vaccine uptake in Ghana: Factors influencing parents' willingness to allow vaccination of their children under five (5) years

BACKGROUND

Malaria is a substantial health burden in Ghana, particularly among children. Despite the availability of malaria vaccines, uptake remains low. Notwithstanding, there is a paucity of nationally representative studies on the factors driving hesitance towards the new malaria vaccine. In response, this study, guided by the Theory of Planned Behaviors (TPB), seeks to understand the determinants of child malaria vaccine uptake in Ghana to inform strategies for improving coverage.

MATERIALS AND METHODS

We employed multiple regression model to examine the association between maternal awareness, socioeconomic status, ethnicity, geographical location, and vaccine uptake using data from the 2019 Ghana Malaria Indicator Survey (MIS).

RESULTS

Maternal awareness of vaccine (OR = 2.200; P<0.01) significantly predicted higher likelihood of vaccine uptake. Household wealth was associated with child vaccination as parents in middle-income households (OR = 9.342; P<0.01), and those in poorest households (OR = 9.409; P<0.05) recorded higher likelihood of allowing their children to be vaccinated. With regards to ethnicity, parents from the Mande ethnic group (OR = 0.106; P<0.05) were less likely to allow their children to be vaccinated when compared to parents from the Akan ethnic group. Knowing that malaria is covered by National Health Insurance (OR = 2.407; P<0.05) was associated with higher likelihood of allowing child vaccination compared to not knowing. More so, geographical variations were observed as parents who lived in rural areas (OR = 0.254; P<0.05) were significantly less likely to allow vaccination of their children compared to those in urban areas.

CONCLUSIONS

Enhancing awareness through education campaigns can improve child malaria vaccine coverage. Observing socioeconomic disparities in uptake and ensuring equitable access to vaccines are vital. Tailored strategies considering ethnic background and geographical location, can as well enhance acceptance of the vaccine. This study provides valuable insights for developing effective strategies to reduce the burden of malaria in children and improve coverage of uptake. This study underscores the need to improve parental awareness and the relevance of the vaccine in preventing child mortality.

Revolutionizing Malaria Vector Control: The Importance of Accurate Species Identification through Enhanced Molecular Capacity

Many factors, such as the resistance to pesticides and a lack of knowledge of the morphology and molecular structure of malaria vectors, have made it more challenging to eradicate malaria in numerous malaria-endemic areas of the globe. The primary goal of this review is to discuss malaria vector control methods and the significance of identifying species in vector control initiatives. This was accomplished by reviewing methods of molecular identification of malaria vectors and genetic marker classification in relation to their use for species identification. Due to its specificity and consistency, molecular identification is preferred over morphological identification of malaria vectors. Enhanced molecular capacity for species identification will improve mosquito characterization, leading to accurate control strategies/treatment targeting specific mosquito species, and thus will contribute to malaria eradication. It is crucial for disease epidemiology and surveillance to accurately identify the Plasmodium spp. that are causing malaria in patients. The capacity for disease surveillance will be significantly increased by the development of more accurate, precise, automated, and high-throughput diagnostic techniques. In conclusion, although morphological identification is quick and achievable at a reduced cost, molecular identification is preferred for specificity and sensitivity. To achieve the targeted malaria elimination goal, proper identification of vectors using accurate techniques for effective control measures should be prioritized.

Malaria treatment health seeking behaviors among international students at the University of Ghana Legon

INTRODUCTION

Appropriate management of malaria demands early health seeking behaviour upon suspicion of malaria-like symptoms. This study examined malaria treatment seeking behaviour and associated factors among international students at University of Ghana.

METHODS

The study used a cross-sectional and quantitative approach. Data collection was undertaken using a structured questionnaire administered on a random sample of 264 international students. Data obtained on malaria treatment and factors influencing treatment behaviors were analyzed using IBM, SPSS Statistics version 22. Associations between individual characteristics and Malaria treatment seeking behavior was assessed by Pearson Chi-square(X2) test of independence. Binary logistic regression model was built using a backwards Wald approach, with variables retained at Wald p-value <0.05.

RESULTS

The findings show that 35% of the respondents obtained self-prescribed antimalarial at their utmost first choice of Malaria treatment. At bivariate level, a significant relationship between Malaria health-care seeking behaviour and:- Respondents continent, X2(1, N = 264) = 7.936, p = .005; Service accessibility, X2(1, N = 264) = 7.624, p = .006; Wait time, X2(1, N = 264) = 22.514, p <0.001; Treatment cost, X2(1, N = 264) = 97.160, p <0.001; Health insurance, X2(1, N = 264) = 5.837, p = 0.016, and Perceived staff attitude, X2(1, N = 264) = 18.557, p < 0.001. At multivariable analysis, inappropriate malaria health seeking behaviours was associated with low perceived service accessibility as (≥30mins) (aOR = 6.67; p<0.001), perceived long wait time (≥30mins), (aOR = 5.94; p = 0.015), perceived treatment cost affordability (<15 GHC) (aOR = 19.88; p<0.001) and age group: -34-41years (aOR = 8.83; p<0.001).

CONCLUSION

There were widespread inappropriate health-care seeking behavior for Malaria treatment among international students. Improving accessibility to malaria treatment services, reducing wait time at health facilities and the treatment cost will address inappropriate malaria treatment health seeking behaviours among the international students.

Understanding the China-Tanzania Malaria Control Project: lessons learned from a multi-stakeholder qualitative study

Background

Tanzania is among the countries with the highest malaria cases and deaths worldwide, where vulnerable populations have been severely affected due to poverty and weakness in health system and infrastructure. The China-Tanzania Malaria Control Project (the Project) was a two-phase global health intervention project implemented between 2015 and 2021 that aimed to transfer project-designated intervention experience in malaria elimination to the Tanzanian health system. This study aims to identify the barriers and facilitators encountered during the Project and to improve our understanding of the emerging phenomenon of South-South global health collaboration.

Methods

We conducted thematic analysis of qualitative data collected from a purposive sample of 14 participants from multiple stakeholders including project management office, project implementation agency, funding partners and external evaluators of the Project. A conceptual framework was developed to construct the interviews guides. The interviews were transcribed verbatim, crossover checked, translated into English, and analyzed with NVivo 12.0. We conducted the open coding followed by the axial coding based on the Grounded Theory to generate themes and subthemes, and identified key influencing factors that aided or hindered the malaria control in Tanzania.

Results

The findings suggested that malaria control strategies should largely be tailored due to varied socioeconomic contexts. The perceived enablers in practice include project-designated intervention experiences and technologies, professional and self-learning capabilities of the implementation team, sustainable financial assistance, and support from the international partners. The barriers include the shortage of global health talents, existing gaps to meet international standards, defects in internal communication mechanisms, inadequacy of intergovernmental dialogue, and limitations in logistical arrangements. A checklist and policy implications for China's future engagement in malaria control in resource-limited settings have been proposed.

Conclusions

The initiative of Health Silk Road has generated strong global interest in promoting development assistance in health. In the hope of generalizing the evidence-based interventions to high malaria-endemic countries in Africa, the need for China to carefully face the challenges of funding gaps and the lack of support from recipient governments remains ongoing. It is recommended that China should form an institutionalized scheme and sustainable funding pool to ensure the steady progress of development assistance in health.

Curcumin or quercetin loaded nutriosomes as oral adjuvants for malaria infections

Artemisinin, curcumin or quercetin, alone or in combination, were loaded in nutriosomes, special phospholipid vesicles enriched with Nutriose FM06®, a soluble dextrin with prebiotic activity, that makes these vesicles suitable for oral delivery. The resulting nutriosomes were sized between 93 and 146 nm, homogeneously dispersed, and had slightly negative zeta potential (around -8 mV). To improve their shelf life and storability over time, vesicle dispersions were freeze-dried and stored at 25 °C. Results confirmed that their main physico-chemical characteristics remained unchanged over a period of 12 months. Additionally, their size and polydispersity index did not undergo any significant variation after dilution with solutions at different pHs (1.2 and 7.0) and high ionic strength, mimicking the harsh conditions of the stomach and intestine. An in vitro study disclosed the delayed release of curcumin and quercetin from nutriosomes (∼53% at 48 h) while artemisinin was quickly released (∼100% at 48 h). Cytotoxicity assays using human colon adenocarcinoma cells (Caco-2) and human umbilical vein endothelial cells (HUVECs) proved the high biocompatibility of the prepared formulations. Finally, in vitro antimalarial activity tests, assessed against the 3D7 strain of Plasmodium falciparum, confirmed the effectiveness of nutriosomes in the delivery of curcumin and quercetin, which can be used as adjuvants in the antimalaria treatment. The efficacy of artemisinin was also confirmed but not improved. Overall results proved the possible use of these formulations as an accompanying treatment of malaria infections.

Effectiveness of health education interventions to improve malaria knowledge and insecticide-treated nets usage among populations of sub-Saharan Africa: systematic review and meta-analysis

Introduction

Malaria health education intervention is a community-directed approach that has long been considered important in preventing malaria in sub-Saharan Africa. However, its effectiveness is being questioned due to a lack of strong evidence. We aim to synthesize the evidence of the impact of health education on malaria knowledge and insecticide-treated nets (ITN) usage. Specifically, we analyzed the odds of correctly answering malaria-related questions and the odds of using ITN between the intervention and control groups.

Methods

Experimental and observational studies conducted in sub-Saharan Africa between 2000 and 2021 which had quantitatively evaluated the impact of health education interventions on malaria knowledge and ITN usage were included in the review.

Results

A total of 11 studies (20,523 participants) were included. Four studies used educational interventions to teach appropriate ITN strategies and promote ITN usage. Two others focused on improving knowledge of malaria transmission, prevention, treatment, and its signs and symptoms. The remaining five studies assessed both ITN use and malaria knowledge. Of these, 10 were eligible for meta-analysis. On average, the odds of a person in the intervention group reporting better malaria knowledge (odds ratio 1.30, 95% CI: 1.00 to 1.70, p = 0.05) and higher ITN usage (odds ratio 1.53, 95% CI: 1.02 to 2.29, p = 0.004) increased significantly after receiving health education interventions compared to those in the control group. The odds of ITN usage also substantially increased when the interventions were based on a theory or model (odds ratio 5.27, 95% CI: 3.24 to 8.58, p = 0.05).

Discussion

Our review highlights sub-Saharan Africa's various health education strategies to curb malaria over the past two decades. Meta-analysis findings show that health education interventions are moderately effective in improving malaria knowledge and ITN usage and have contributed to the effort of global malaria strategy.

Limited genetic variations of the Rh5-CyRPA-Ripr invasion complex in Plasmodium falciparum parasite population in selected malaria-endemic regions, Kenya

The invasion of human erythrocytes by Plasmodium falciparum merozoites requires interaction between parasite ligands and host receptors. Interaction of PfRh5-CyRPA-Ripr protein complex with basigin, an erythrocyte surface receptor, via PfRh5 is essential for erythrocyte invasion. Antibodies raised against each antigen component of the complex have demonstrated erythrocyte invasion inhibition, making these proteins potential blood-stage vaccine candidates. Genetic polymorphisms present a significant challenge in developing efficacious vaccines, leading to variant-specific immune responses. This study investigated the genetic variations of the PfRh5 complex proteins in P. falciparum isolates from Lake Victoria islands, Western Kenya. Here, twenty-nine microscopically confirmed P. falciparum field samples collected from islands in Lake Victoria between July 2014 and July 2016 were genotyped by whole genome sequencing, and results compared to sequences mined from the GenBank database, from a study conducted in Kilifi, as well as other sequences from the MalariaGEN repository. We analyzed the frequency of polymorphisms in the PfRh5 protein complex proteins, PfRh5, PfCyRPA, PfRipr, and PfP113, and their location mapped on the 3D protein complex structure. We identified a total of 58 variants in the PfRh5 protein complex. PfRh5 protein was the most polymorphic with 30 SNPs, while PfCyRPA was relatively conserved with 3 SNPs. The minor allele frequency of the SNPs ranged between 1.9% and 21.2%. Ten high-frequency alleles (>5%) were observed in PfRh5 at codons 147, 148, 277, 410, and 429 and in PfRipr at codons 190, 255, 259, and 1003. A SNP was located in protein-protein interaction region C203Y and F292V of PfRh5 and PfCyRPA, respectively. Put together, this study revealed low polymorphisms in the PfRh5 invasion complex in the Lake Victoria parasite population. However, the two mutations identified on the protein interaction regions prompts for investigation on their impacts on parasite invasion process to support the consideration of PfRh5 components as potential malaria vaccine candidates.

Antimalarial and Cytotoxic Activity of Native Plants Used in Cabo Verde Traditional Medicine

Medicinal plants have historically been a source of drugs in multiple applications, including the treatment of malaria infections. The Cabo Verde archipelago harbors a rich diversity of native plants, most of which are used for medicinal purposes. The present study investigated the in vitro antiplasmodial activities of four native plants from Cabo Verde (i.e., Artemisia gorgonum, Lavandula rotundifolia, Sideroxylon marginatum, and Tamarix senegalensis). Traditional preparations of these medicinal plants, namely aqueous extracts (infusions) and ethanolic extracts, were tested against both chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains using the SYBR Green detection method. The in vitro cytotoxicity was evaluated in Caco-2 and PLP2 cells using a sulforhodamine B colorimetric assay. An ethanolic extract of A. gorgonum and infusions of T. senegalensis exhibited high antiplasmodial activities (EC₅₀ < 5 μg/mL) without cytotoxicity (GI₅₀ > 400 μg/mL). Extracts of L. rotundifolia and S. marginatum exhibited moderate activities, with EC₅₀ values ranging from 10-30 μg/mL. The A. gorgonum ethanolic extract showed activity toward early ring stages, and parasites treated with the T. senegalensis infusions progressed to the early trophozoite stage, although did not develop further to the late trophozoite or schizont stages. Antimalarial activities and the lack of cytotoxicity of the extracts are reported in the present study and support previous claims by traditional practitioners for the use of these plants against malaria while suggesting their ethnopharmacological usefulness as future antimalarials.

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.

Plasmodium vivax: the potential obstacles it presents to malaria elimination and eradication

Initiatives to eradicate malaria have a good impact on P. falciparum malaria worldwide. P. vivax, however, still presents significant difficulties. This is due to its unique biological traits, which, in comparison to P. falciparum, pose serious challenges for malaria elimination approaches. P. vivax's numerous distinctive characteristics and its ability to live for weeks to years in liver cells in its hypnozoite form, which may elude the human immune system and blood-stage therapy and offer protection during mosquito-free seasons. Many malaria patients are not fully treated because of contraindications to primaquine use in pregnant and nursing women and are still vulnerable to P. vivax relapses, although there are medications that could radical cure P. vivax. Additionally, due to CYP2D6's highly variable genetic polymorphism, the pharmacokinetics of primaquine may be impacted. Due to their inability to metabolize PQ, some CYP2D6 polymorphism alleles can cause patients to not respond to treatment. Tafenoquine offers a radical treatment in a single dose that overcomes the potentially serious problem of poor adherence to daily primaquine. Despite this benefit, hemolysis of the early erythrocytes continues in individuals with G6PD deficiency until all susceptible cells have been eliminated. Field techniques such as microscopy or rapid diagnostic tests (RDTs) miss the large number of submicroscopic and/or asymptomatic infections brought on by reticulocyte tropism and the low parasitemia levels that accompany it. Moreover, P. vivax gametocytes grow more quickly and are much more prevalent in the bloodstream. P. vivax populations also have a great deal of genetic variation throughout their genome, which ensures evolutionary fitness and boosts adaptation potential. Furthermore, P. vivax fully develops in the mosquito faster than P. falciparum. These characteristics contribute to parasite reservoirs in the human population and facilitate faster transmission. Overall, no genuine chance of eradication is predicted in the next few years unless new tools for lowering malaria transmission are developed (i.e., malaria elimination and eradication). The challenging characteristics of P. vivax that impede the elimination and eradication of malaria are thus discussed in this article.

Utilization of 18s ribosomal RNA LAMP for detecting Plasmodium falciparum in microscopy and rapid diagnostic test negative patients

In this study, Plasmodium falciparum was detected in patients that were declared negative for malaria microscopy and rapid diagnostic test kit (mRDT), using Plasmodium 18s rRNA loop-mediated isothermal amplification (LAMP) technique. The main aim of this study was to assess the usefulness of LAMP assay for detecting pre-clinical malaria, when microscopy and mRDT were less sensitive. DNA was obtained from 100 μL of whole blood using the boil and spin method. Subsequently, the Plasmodium 18s rRNA LAMP assay was performed to amplify the specific Plasmodium 18s rRNA gene. Microscopy and mRDT negative samples [697/2223 (31.2%)] were used for this study. Compared to frequencies obtained for the other demographic variables, most of the patients were < 6 years (37.7%), females (59.0%), peri-urban dwellers (39.0%) and patients that sought outpatient department services (39.3%). Overall, the prevalence of Plasmodium 18s rRNA was 17.5%. when stratified by study variables, Plasmodium 18s rRNA LAMP positivity was higher in patients over 30 years [58/122 (54.2%)], males [69/122 (56.5%)], rural dwellers [69/122 (56.5%)] and patients that sought OPD services [68/122 (55.7%)]. The risk of being infected with Plasmodium when routine tests were negative was higher in 15-30-year group (OR = 3.03, 95% CI: 1.6-5.8, p = 0.0007), patients > 30 years (OR = 15.2, 95% CI: 8.3-27.7, p<0.001), males (OR = 2.1, 95% CI: 1.4-3.2, p = 0.0002) and rural dwellers (OR = 2.2, 95% CI:1.4-3.6, p = 0.0009). However, risk was lower in post-natal children (OR = 0.3, 95% CI: 0.18-0.51, p<0.001). Majority (81.5%) of the infected patients presented with headache, herpes labialis, diarrhea and vomiting. We demonstrated the lack of sensitivities of microscopy and mRDT for one-time diagnosis of malaria. Therefore, it is essential to utilize a sensitive technique such as Plasmodium 18s rRNA LAMP to increase the detection rate of Plasmodium infection.

Increasing challenges of malaria control in sub-Saharan Africa: Priorities for public health research and policymakers

The ever-increasing cases and mortality due to malaria remains one of the most important public health threats, especially in sub-Saharan Africa-where this burden is considerably high. In 2020, sub-Saharan Africa accounted for about 95% of all cases and 96% of all malaria deaths with about 80% of these deaths reported in children under the age of 5. This review, adopting a public health focus, aimed to understand the challenges of malaria control in sub-Saharan Africa despite ongoing public health interventions. Our review highlights two important findings. First, the increasing resistance of malaria parasites to artemisinin-based combination therapy (ACT) and its partner drugs coupled with increased vector resistance to pyrethroids and insecticides is reversing the progress of public health interventions in keeping malaria under control. Second, the wanning for the efficacy of the WHO-approved vaccine i.e. RTS,S from 60 to 70% following 18 months of observation, and its short-term availability remains an impediment to achieving the WHO target of producing malaria vaccines with more than 75% efficacy by 2030. Our findings underline the need to reassess research priorities with a focus on vaccine production in sub-Saharan Africa. Furthermore, African governments and policymakers must be committed to invest both the political and financial capital in vaccine production and distribution.

Malaria prevalence and risk factors among patients visiting Mizan Tepi University Teaching Hospital, Southwest Ethiopia

Background

Ethiopia is among sub-Saharan African countries with a high number of malaria cases each year, with most of the landmass favoring the breeding of the vectors. There have been extensive efforts to control and prevent the transmission of malaria, which is part of the country’s prevention-based health policy.

Objective

This study aimed to determine malaria prevalence and associated risk factors among patients visiting Mizan-Tepi University Teaching Hospital (MTUTH).

Materials and methods

A cross-sectional study was conducted from September to December 2021 among patients visiting MTUTH, Southwest Ethiopia. A pretested structured questionnaire was used to collect sociodemographic data, and a capillary blood sample was collected after obtaining written informed consent from the study participants. The data were entered into Epi-data manager (v4.0.2.101) and analyzed with SPSS version 25.0, with a P-value of < 0.05 set as a significance.

Results

A total of 439 patients participated, of which 20.7% (91) were positive for malaria parasites, with a higher prevalence observed among the age group interval of 25–34 years (5.5%). Inadequate access to insecticide-treated bed net (ITN) 23.9% (105) and a low level of ITN usage 20.5% (90) were recorded. Patients living in areas of stagnant water were more likely to get infected with the malaria parasite (AOR = 16.191, 95% CI: 9.137, 28.692) compared to those who live away from stagnant water, and individuals living in houses not sprayed with insecticides were more susceptible to malaria infection (AOR = 0.215, 95% CI: 0.128, 0.360).

Conclusion

The overall malaria prevalence in this study was 20.7% (91), which proves that malaria remains a major threat to the communities in the study area, with Plasmodium falciparum contributing to most of the cases. Improving the habits of ITN usage and indoor residual spray through health education may help to reduce the impact of malaria in the study area.

Malaria and Helminthic Co-Infection during Pregnancy in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

Malaria and helminthic co-infection during pregnancy causes fetomaternal haemorrhage and foetal growth retardation. This study determined the pooled burden of pregnancy malaria and helminthic co-infection in sub-Saharan Africa. CINAHL, EMBASE, Google Scholar, Scopus, PubMed, and Web of Science databases were used to retrieve data from the literature, without restricting language and publication year. The Joanna Briggs Institute's critical appraisal tool for prevalence studies was used for quality assessment. STATA Version 14.0 was used to conduct the meta-analysis. The I2 statistics and Egger's test were used to test heterogeneity and publication bias. The random-effects model was used to estimate the pooled prevalence at a 95% confidence interval (CI). The review protocol has been registered in PROSPERO, with the number CRD42019144812. In total, 24 studies (n = 14,087 participants) were identified in this study. The pooled analysis revealed that 20% of pregnant women were co-infected by malaria and helminths in sub-Saharan Africa. The pooled prevalence of malaria and helminths were 33% and 35%, respectively. The most prevalent helminths were Hookworm (48%), Ascaris lumbricoides (37%), and Trichuris trichiura (15%). Significantly higher malaria and helminthic co-infection during pregnancy were observed. Health systems in sub-Saharan Africa must implement home-grown innovative solutions to underpin context-specific policies for the early initiation of effective intermittent preventive therapy.

Malaria diagnostic methods with the elimination goal in view

Malaria control measures have been in use for years but have not completely curbed the spread of infection. Ultimately, global elimination is the goal. A major playmaker in the various approaches to reaching the goal is the issue of proper diagnosis. Various diagnostic techniques were adopted in different regions and geographical locations over the decades, and these have invariably produced diverse outcomes. In this review, we looked at the various approaches used in malaria diagnostics with a focus on methods favorably used during pre-elimination and elimination phases as well as in endemic regions. Microscopy, rapid diagnostic testing (RDT), loop-mediated isothermal amplification (LAMP), and polymerase chain reaction (PCR) are common methods applied depending on prevailing factors, each with its strengths and limitations. As the drive toward the elimination goal intensifies, the search for ideal, simple, fast, and reliable point-of-care diagnostic tools is needed more than ever before to be used in conjunction with a functional surveillance system supported by the ideal vaccine.