Knowledge, and attitude of service user of intermittent preventive treatment of malaria in pregnancy using sulfadoxine pyrimethamine in the Volta Region of Ghana.

BACKGROUND: Malaria in pregnancy (MiP) is a condition that can be prevented by using intermittent preventive treatment using Sulfadoxine-pyrimethamine. However, despite all the effort to reduce the consequences of MiP for the woman, the unborn child, and the neonate, the knowledge of Intermittent Preventive Treatment of Malaria in pregnancy using sulfadoxine-pyrimethamine (IPTp-SP) is low in most malaria-endemic countries, including Ghana. Thus, the need to examine knowledge, and attitude of service users of intermittent preventive treatment of malaria in pregnancy using sulfadoxine-pyrimethamine. METHODS: The study was a cross-sectional survey of two selected districts in the Volta Region of Ghana. The study participants were randomly selected from communities within Nkwanta North and North Tongu District. In all a total of 438 mothers who have delivered in the past 24 months were selected for the study. The women were interviewed using a structured questionnaire and the bivariate and multivariable logistic regression results presented in tables. RESULTS: The level of knowledge, and attitude were reported as 45.9% and 58.9% respectively. Knowledge of the service user is determined by the level of education of the women. The attitude of the service user is determined by making 4-7 visits during ANC, Gestational age at booking for ANC is 4-7 weeks, income level between 100 to 999, partner educational level above Middle/JHS/JSS, and age of a partner is above 40 years. CONCLUSION: The findings from the present studies highlighted important factor such as number of antenatal visits that affect both knowledge of services and attitude to use IPTp-SP. Therefore, a community-based health promotion programmes to help to increase knowledges and improved attitude on timely and regular antenatal attendance to promote the benefit of IPTp-SP should be encouraged.

Diagnostic role of Sysmex hematology analyzer in the detection of malaria: A systematic review and meta-analysis.

BACKGROUND: Malaria control depends primarily on rapid and accurate diagnosis followed by successful treatment. Light microscopy is still used as a gold standard method for the diagnosis of malaria. The Sysmex hematology analyzer is a novel method for malaria detection. Therefore, the aim of this review was to investigate the diagnostic accuracy of the Sysmex hematology analyzer for malaria diagnosis. METHODS: Electronic databases like PubMed, PubMed Central, Science Direct databases, Google Scholar, and Scopus were used to find relevant articles from April to June 14, 2023. The studies' methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Using Review Manager 5.4.1, the estimates of sensitivity and specificity, as well as their 95% confidence intervals, were shown in forest plots. Midas software in Stata 14.0 was utilized to calculate the summary estimates of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio. Heterogeneity was assessed by using I2 statistics. In addition, publication bias was assessed using a funnel plot and Deeks' test. Sub-group and meta- regression analysis were also performed. RESULTS: A total of 15 studies were assessed for diagnostic accuracy. The sensitivity and specificity of Sysmex hematology analyzer for studies ranged from 46% to 100% and 81% to 100%, respectively. The summary estimate of sensitivity and specificity of Sysmex hematology analyzer were 95% (95% CI: 85%-99%) and 99% (95% CI: 97%-100%), respectively. It had excellent diagnostic accuracy. There were significant heterogeneity among the studies included in this meta-analysis. The summary estimate of sensitivity and specificity of Sysmex hematology analyzer using polymerase chain reaction as the gold standard was 97.6% (95% CI: 83.2, 99.7) and 99.4% (98.5, 99.8), respectively. CONCLUSION: In this review, Sysmex hematology analyzer had excellent diagnostic accuracy. Therefore, it could be used as an alternate diagnostic tool for malaria diagnosis in the hospital and health center. TRIAL REGISTRATION: Systematic review registration PROSPERO (2023: CRD42023427713). https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023427713.

Effectiveness of malaria chemoprevention in the first two years of life in Cameroon and Côte d'Ivoire compared to standard of care: study protocol for a population-based prospective cohort impact evaluation study.

BACKGROUND: Perennial malaria chemoprevention (PMC) is a chemoprevention strategy endorsed by the World Health Organization (WHO) and is increasingly being adopted by National Malaria Programmes. PMC aims to reduce morbidity and mortality caused by malaria and anaemia in in young children through provision of antimalarial drugs at routine contact points with the local health system. This study aims to evaluate the impact of the programmatically-implemented country-tailored PMC programmes targeting children up to two years of age using sulfadoxine-pyrimethamine (SP) on the incidence of malaria and anaemia in children in Cameroon and Côte d'Ivoire. METHODS: We will assess the impact of PMC using passive and active monitoring of a prospective observational cohort of children up to 36 months of age at recruitment in selected study sites in Cameroon and Côte d'Ivoire. The primary and secondary outcomes include malaria, anaemia and malnutrition incidence. We will also conduct a time-series analysis of passively detected malaria and anaemia cases comparing the periods before and after PMC introduction. This study is powered to detect a 30% and 40% reduction of malaria incidence compared to the standard of care in Cameroon and Côte d'Ivoire, respectively. DISCUSSION: This multi-country study aims to provide evidence of the effectiveness of PMC targeting children in the first two years of life on malaria and anaemia and will provide important information to inform optimal operationalization and evaluation of this strategy. TRIAL REGISTRATION: Cameroon - NCT05889052; Côte d'Ivoire - NCT05856357.

Perceived barriers and opportunities for the introduction of post-discharge malaria chemoprevention (PDMC) in five sub-Saharan countries: a qualitative survey amongst malaria key stakeholders.

BACKGROUND: Post-discharge malaria chemoprevention (PDMC) is an intervention aimed at reducing morbidity and mortality in patients hospitalized with severe anaemia, with its effectiveness established in several clinical trials. The aim of this study was to better understand factors that would influence the scale up of this intervention, and to identify preferences for two delivery mechanisms, facility-based or community-based. METHODS: Forty-six qualitative individual interviews were conducted in five sub-Saharan countries amongst malaria key opinion leaders and national decision makers. Findings were analysed following a thematic inductive approach. RESULTS: Half of participants were familiar with PDMC, with a satisfactory understanding of the intervention. Although PDMC was perceived as beneficial by most respondents, there was some unclarity on the target population. Both delivery approaches were perceived as valuable and potentially complementary. From an adoption perspective, relevant evidence generation, favorable policy environment, and committed funding were identified as key elements for the scale up of PDMC. CONCLUSIONS: The findings suggest that although PDMC was perceived as a relevant tool to prevent malaria, further clarification was needed in terms of the relevant patient population, delivery mechanisms, and more evidence should be generated from implementation research to ensure policy adoption and funding.

Larvicidal potential of Trachyspermum ammi essential oil and Delphinium speciosum extract against malaria, dengue, and filariasis mosquito vectors.

Mosquito-borne diseases, such as malaria, dengue, and Zika, pose major public health challenges globally, affecting millions of people. The growing resistance of mosquito populations to synthetic insecticides underscores the critical need for effective and environmentally friendly larvicides. Although chemical pesticides can initially be effective, they often lead to negative environmental consequences and health hazards for non-target species, including humans. This study aimed to evaluate the larvicidal effects of Trachyspermum ammi essential oil and Delphinium speciosum extract on the larvae of three major mosquito species: Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Mosquito larvae of Ae. aegypti, An. stephensi, and Cx. quinquefasciatus were reared under controlled laboratory conditions. The larvicidal activity of T. ammi essential oil and D. speciosum extract was evaluated through standard bioassays, using various concentrations of essential oils (10, 20, 40, 80, and 160 ppm) and extracts (160, 320, 640, 1280, and 2560 ppm) to determine the lethal concentration (LC50) values after 24 h of exposure. Fresh plant materials were collected, with the essential oil extracted via hydro-distillation, and the extract prepared using methanol solvent extraction. The chemical composition of T. ammi essential oil was examined using gas chromatography-mass spectrometry (GC-MS). Additionally, the preliminary analysis of the chemical compounds in D. speciosum extract was carried out using thin layer chromatography (TLC) and nuclear magnetic resonance spectroscopy (NMR) techniques. The results indicated that the essential oil of T. ammi exhibited more effective larvicidal activity compared to the D. speciosum extract. Specifically, the essential oil demonstrated LC50 values of 18 ppm for Cx. quinquefasciatus and 19 ppm for Ae. aegypti. In contrast, the D. speciosum extract showed the strongest larvicidal effect against An. stephensi, with an LC50 of 517 ppm. Concentrations of 40 ppm of the essential oil and 1280 ppm of the extract resulted in 100% mortality across all three species. Both the essential oil of T. ammi and the D. speciosum extract exhibited concentration-dependent larvicidal activity, and these results were statistically significant (p < 0.001) compared to the no-treatment group. GC-MS analysis revealed thymol (88.95%), o-cymen-5-ol (4.11%), and γ-terpinene (2.10%) as the major constituents of the T. ammi essential oil. Additionally, TLC verified the presence of alkaloids in both chloroform and methanolic extracts. Proton NMR identified a diterpene structure for these alkaloids. These findings suggest that T. ammi essential oil is a promising candidate for natural mosquito control strategies. Given its efficacy, further research is warranted to explore its potential in integrated vector management programs.

Fabrication of Phytosome with Enhanced Activity of Sonneratia alba: Formulation Modeling and in vivo Antimalarial Study.

Introduction: Sonneratia alba extract exhibits antimalarial activity, mainly due to its secondary metabolites-naphthoquinones, flavonoids, tannins, and saponins-where naphthoquinone is the primary active component. However, its low bioavailability limits its effectiveness. To improve this, a phytosome-based vesicular system was proposed. This study focused on formulating a phytosome with S. alba and developing a predictive model to enhance its antimalarial activity. Methods: Phytosomes were produced using antisolvent precipitation and optimized with 3-factor, 3-level Box-behnken model. Particle size, zeta potential, and entrapment efficiency were assessed. The optimized phytosomes were characterized by their physical properties and release profiles. Their antimalarial activity was tested in white BALB/c mice infected with Plasmodium berghei using Peter's 4-day suppressive test. Results: The optimal phytosome formulation used a phospholipid-to-extract ratio of 1:3, reflux temperature of 50°C, and a duration of 2.62 hours. The phytosomes had a particle size of 471.8 nm, a zeta potential of -54.1 mV, and an entrapment efficiency (EE) of 82.4%. In contrast, the phytosome-fraction showed a particle size of 233.4 nm, a zeta potential of -61.5 mV, and an EE of 87.08%. TEM analysis confirmed both had a spherical shape. In vitro release rates at 24 hours were 86.2 for the phytosome-extract and 95.9% for the phytosome-fraction, compared to 46.9% and 37.7% for the extract and fraction alone. Overall, the phytosome formulation demonstrated good stability. The actual experimental values closely matched the predicted values from the Box-Behnken model, indicating a high degree of accuracy in the model. Additionally, the phytosomes exhibited significantly greater antimalarial activity than the S. alba extract and fraction alone. Conclusion: The findings indicated that the vesicular formulation in phytosomes can enhance the antimalarial activity of S. alba extract and fraction.

Spatio-temporal dynamics of malaria in Rwanda between 2012 and 2022: a demography-specific analysis.

BACKGROUND: Despite global efforts to reduce and eventually interrupt malaria transmission, the disease remains a pressing public health problem, especially in sub-Saharan Africa. This study presents a detailed spatio-temporal analysis of malaria transmission in Rwanda from 2012 to 2022. The main objective was to gain insights into the evolving patterns of malaria and to inform and tailor effective public health strategies. METHODS: The study used yearly aggregated data of malaria cases from the Rwanda health management information system. We employed a multifaceted analytical approach, including descriptive statistics and spatio-temporal analysis across three demographic groups: children under the age of 5 years, and males and females above 5 years. Bayesian spatially explicit models and spatio scan statistics were utilised to examine geographic and temporal patterns of relative risks and to identify clusters of malaria transmission. RESULTS: We observed a significant increase in malaria cases from 2014 to 2018, peaking in 2016 for males and females aged above 5 years with counts of 98,645 and 116,627, respectively and in 2018 for under 5-year-old children with 84,440 cases with notable geographic disparities. Districts like Kamonyi (Southern Province), Ngoma, Kayonza and Bugesera (Eastern Province) exhibited high burdens, possibly influenced by factors such as climate, vector control practices, and cross-border dynamics. Bayesian spatially explicit modeling revealed elevated relative risks in numerous districts, underscoring the heterogeneity of malaria transmission in these districts, and thus contributing to an overall rising trend in malaria cases until 2018, followed by a subsequent decline. Our findings emphasize that the heterogeneity of malaria transmission is potentially driven by ecologic, socioeconomic, and behavioural factors. CONCLUSIONS: The study underscores the complexity of malaria transmission in Rwanda and calls for climate adaptive, gender-, age- and district-specific strategies in the national malaria control program. The emergence of both artemisinin and pyrethoids resistance and persistent high transmission in some districts necessitates continuous monitoring and innovative, data-driven approaches for effective and sustainable malaria control.

Whole-genome sequencing of major malaria vectors reveals the evolution of new insecticide resistance variants in a longitudinal study in Burkina Faso.

BACKGROUND: Intensive deployment of insecticide based malaria vector control tools resulted in the rapid evolution of phenotypes resistant to these chemicals. Understanding this process at the genomic level is important for the deployment of successful vector control interventions. Therefore, longitudinal sampling followed by whole genome sequencing (WGS) is necessary to understand how these evolutionary processes evolve over time. This study investigated the change in genetic structure and the evolution of the insecticide resistance variants in natural populations of Anopheles gambiae over time and space from 2012 to 2017 in Burkina Faso. METHODS: New genomic data have been generated from An. gambiae mosquitoes collected from three villages in the western part of Burkina Faso between 2012 and 2017. The samples were whole-genome sequenced and the data used in the An. gambiae 1000 genomes (Ag1000G) project as part of the Vector Observatory. Genomic data were analysed using the analysis pipeline previously designed by the Ag1000G project. RESULTS: The results showed similar and consistent nucleotide diversity and negative Tajima's D between An. gambiae sensu stricto (s.s.) and Anopheles coluzzii. Principal component analysis (PCA) and the fixation index (FST) showed a clear genetic structure in the An. gambiae sensu lato (s.l.) species. Genome-wide FST and H12 scans identified genomic regions under divergent selection that may have implications in the adaptation to ecological changes. Novel voltage-gated sodium channel pyrethroid resistance target-site alleles (V402L, I1527T) were identified at increasing frequencies alongside the established alleles (Vgsc-L995F, Vgsc-L995S and N1570Y) within the An. gambiae s.l. POPULATIONS: Organophosphate metabolic resistance markers were also identified, at increasing frequencies, within the An. gambiae s.s. populations from 2012 to 2017, including the SNP Ace1-G280S and its associated duplication. Variants simultaneously identified in the same vector populations raise concerns about the long-term efficacy of new generation bed nets and the recently organophosphate pirimiphos-methyl indoor residual spraying in Burkina Faso. CONCLUSION: These findings highlighted the benefit of genomic surveillance of malaria vectors for the detection of new insecticide resistance variants, the monitoring of the existing resistance variants, and also to get insights into the evolutionary processes driving insecticide resistance.

Prospective acceptability of mass drug administration for malaria in Kedougou region in Senegal: a mixed method study.

BACKGROUND: In Senegalese high-burden regions, the existing package of interventions is insufficient to reach the malaria elimination goal. Asymptomatic carriers of Plasmodium contribute significantly to malaria persistence and are not targeted by current interventions. The systematic treatment of all individuals in a community (mass drug administration, MDA) is a relevant intervention to tackle asymptomatic infections. The intervention can only be effective with a high participation of the population and, therefore, depends largely on its acceptability. This study aims to investigate the prospective acceptability of MDA in the Kedougou region to inform its potential use in a future strategy. METHODS: Following a 7-construct theoretical framework, prospective acceptability of MDA implemented in the rainy season was studied. In four villages, a sequential mixed design, from qualitative to quantitative, was used. In November 2021, interviews with healthcare professionals and focus groups with villagers were conducted. Findings from thematic analysis informed the development of a questionnaire administered to individuals aged ≥ 15 years in March 2022. Based on the questionnaire, an acceptability score was constructed and associations with socio-demographic factors were investigated using a linear mixed model. RESULTS: The 7 interviews, the 12 focus groups, and the questionnaire administered to 289 individuals demonstrated a good acceptability of MDA. Two potential barriers were identified: the contradiction of taking a medication without feeling sick and the occurrence of side effects; and four facilitators: the perception of malaria as a burden, a good understanding of MDA, a good perceived effectiveness, and the resulting economic benefits. The average acceptability score was 3.5 (range from -7 to + 7). Young adults aged 15 to 21 had a lower acceptability score compared to the other age groups, indicating an additional barrier to acceptability (ß = -0.78 [-1.67;0.1]). CONCLUSION: MDA is a priori acceptable to communities of Kedougou region in Senegal. Sensitization campaigns co-constructed with the communities, especially targeting young adults, are essential to ensure good acceptability.

Assessment of the efficiency of the routine epidemiological surveillance system for malaria at the Tambacounda Health District, Senegal.

Introduction: as part of the fight against malaria, epidemiological surveillance (ES) is one of the key pillars of the global technical strategy 2016-2030 to combat this disease. However, in the south-east of Senegal, where malaria poses a major public health problem, epidemiological surveillance has until recently been very neglected. To help reduce malaria-related morbidity and mortality in Senegal, an evaluation of the routine malaria ES system was conducted in the Tambacounda Health District in 2021. Methods: we conducted a cross-sectional, descriptive survey of 27 health structures in Tambacounda district from 20th February to 1st March 2022. Results: overall, the routine ES system in the district was acceptable according to its users, with satisfactory tool filling time in 96.3% of the structures in our study, a cumulative completeness of reports at 92% despite a 77% promptness. The data collected at the services delivery points (SDP) level allowed a representativeness of the ES system in 100% of health facilities. The ES system was also rated as simple by 74.1% of SDP managers even though only 55.6% of them were trained. However, the stability of the system was low because 55.6% of SDP had staff to ensure the continuity of ES service despite the availability of management tools (100%) and the telephone network (96.3%). The same was true for the usefulness of the ES because only 25.9% of SDP managers analyzed their produced data. The reported ES and malaria morbidity data were not adequate. On the other hand, the ES system was reactive with a speed of transmission of information at 96.3% and a possibility of rapid diagnosis and management of cases at 100%. Conclusion: the routine malaria ES system at the level of health facilities in Tambacounda District was acceptable, simple, flexible, representative, and responsive. However, an increase in qualified staff at the health posts, capacity strengthening of the ES staff and regular supervision of SDP are needed essentials to make the district's malaria surveillance system more efficient.

The demand for intermittent preventive treatment of malaria in pregnancy using sulfadoxine-pyrimethamine in the Volta Region of Ghana.

BACKGROUND: Malaria in pregnancy (MiP) is a preventable condition leading to maternal and neonatal morbidity and mortality. Invariably, with all the knowledge about the serious consequences of MiP for the woman, the unborn child, and the neonate, the uptake of Intermittent Preventive Treatment of Malaria in pregnancy using sulfadoxine-pyrimethamine (IPTp-SP) is low in most malaria-endemic countries, including Ghana. This study sought to examine the uptake and service user predictors of the implementation of IPTp-SP after the policy upgrade in 2014. METHODS: This cross-sectional survey was carried out in two selected districts in the Volta Region. The study participants were randomly selected from communities within Nkwanta North and North Tongu District. A total of 438 mothers who have delivered in the past 24 months were selected for the study. The women were interviewed on their background, knowledge, and attitude toward the use of IPTp-SP using a structured questionnaire. Multiple logistic regression was done to determine the factors that influence the demand for IPTp-SP. The results were presented in the form of tables. RESULTS: The mean number of antenatal care (ANC) attendance was 5 (SD:2.6) visits per client, with 262 (59.82%) of them getting the 3+ doses of IPTp-SP. Also, a significant 44 (10.1%) of the mothers did not receive any dose of IPTp-SP. Respondents who attended antenatal clinics 4-7 times had 7 (CI:3.9-12.3) times higher uptake of 3+ doses of IPTp-SP as compared to others who attended less than 4 visits. Similarly, women who had 8 or more visits had a 16.1 (CI: 5.9-43.6) times higher chance of getting more than 2 doses of IPTp-SP compared with others who had fewer than 4 attendances. CONCLUSION: The uptake of 3+ doses of IPTp-SP is still lower than the global target of 80%. Thus, the need for innovative interventions aimed at improving antenatal attendance and early booking for IPTp-SP are recommended.

Bovine lactoferrin inhibits Plasmodium berghei growth by binding to heme.

Bovine lactoferrin (bLF) is a 77 kDa glycoprotein that is abundant in bovine breast milk and exerts various bioactive functions, including antibacterial and antiviral functions. Few studies have explored bLF activity against parasites. We found that bLF affects hemozoin synthesis by binding to heme, inhibiting heme iron polymerization necessary for Plasmodium berghei ANKA survival in infected erythrocytes, and also binds to hemozoin, causing it to disassemble. In a challenge test, bLF administration inhibited the growth of murine malaria parasites compared to untreated group growth. To determine whether the iron content of bLF affects the inhibition of malaria growth, we tested bLFs containing different amounts of iron (apo-bLF, native-bLF, and holo-bLF), but found no significant difference in their effects. This indicated that the active sites were located within the bLFs themselves. Further studies showed that the C-lobe domain of bLF can inhibit hemozoin formation and the growth of P. berghei ANKA. Evaluation of pepsin degradation products of the C-lobe identified a 47-amino-acid section, C-1, as the smallest effective region that could inhibit hemozoin formation. This study highlights bLF's potential as a novel therapeutic agent against malaria, underscoring the importance of its non-iron-dependent bioactive sites in combating parasite growth.

Community awareness, knowledge and perception about malaria vaccine in the Kassena-Nankana East Municipality: A descriptive cross-sectional survey.

AIM: To assess community awareness, knowledge and perception of the malaria vaccine. DESIGN: A descriptive cross-sectional survey. METHODS: Multistage sampling was adopted in recruiting 400 participants. A structured questionnaire designed based on study objectives guided data collection. RESULTS: Participants were 18-47 years with a mean age of 30 years. A statistically significant association was observed between socio-demographic characteristics (age, marital status, religion, education) and the awareness of the malaria vaccine. Majority of the participants (n = 190, 86.4%) said the vaccine was for the protection of children and they perceived that the vaccine would improve children's ability to fight diseases (n = 158, 71.8%), hence should be administered to every child (n = 201, 91.4%). Nurses and other health workers should intensify public education on the malaria vaccine. PATIENT OR PUBLIC CONTRIBUTION: Caregivers of children in Kassena-Nankana East Municipality.

Investigating the association between household exposure to Anopheles stephensi and malaria in Sudan and Ethiopia: A case-control study protocol.

BACKGROUND: Endemic African malaria vectors are poorly adapted to typical urban ecologies. However, Anopheles stephensi, an urban malaria vector formerly confined to South Asia and the Persian Gulf, was recently detected in Africa and may change the epidemiology of malaria across the continent. Little is known about the public health implications of An. stephensi in Africa. This study is designed to assess the relative importance of household exposure to An. stephensi and endemic malaria vectors for malaria risk in urban Sudan and Ethiopia. METHODS: Case-control studies will be conducted in 3 urban settings (2 in Sudan, 1 in Ethiopia) to assess the association between presence of An. stephensi in and around households and malaria. Cases, defined as individuals positive for Plasmodium falciparum and/or P. vivax by microscopy/rapid diagnostic test (RDT), and controls, defined as age-matched individuals negative for P. falciparum and/or P. vivax by microscopy/RDT, will be recruited from public health facilities. Both household surveys and entomological surveillance for adult and immature mosquitoes will be conducted at participant homes within 48 hours of enrolment. Adult and immature mosquitoes will be identified by polymerase chain reaction (PCR). Conditional logistic regression will be used to estimate the association between presence of An. stephensi and malaria status, adjusted for co-occurrence of other malaria vectors and participant gender. CONCLUSIONS: Findings from this study will provide evidence of the relative importance of An. stephensi for malaria burden in urban African settings, shedding light on the need for future intervention planning and policy development.

Insights into malaria vectors-plant interaction in a dryland ecosystem.

Improved understanding of mosquito-plant feeding interactions can reveal insights into the ecological dynamics of pathogen transmission. In wild malaria vectors Anopheles gambiae s.l. and An. funestus group surveyed in selected dryland ecosystems of Kenya, we found a low level of plant feeding (2.8%) using biochemical cold anthrone test but uncovered 14-fold (41%) higher rate via DNA barcoding targeting the chloroplast rbcL gene. Plasmodium falciparum positivity was associated with either reduced or increased total sugar levels and varied by mosquito species. Gut analysis revealed the mosquitoes to frequently feed on acacia plants (~ 89%) (mainly Vachellia tortilis) in the family Fabaceae. Chemical analysis revealed 1-octen-3-ol (29.9%) as the dominant mosquito attractant, and the sugars glucose, sucrose, fructose, talose and inositol enriched in the vegetative parts, of acacia plants. Nutritional analysis of An. longipalpis C with high plant feeding rates detected fewer sugars (glucose, talose, fructose) compared to acacia plants. These results demonstrate (i) the sensitivity of DNA barcoding to detect plant feeding in malaria vectors, (ii) Plasmodium infection status affects energetic reserves of wild anopheline vectors and (iii) nutrient content and olfactory cues likely represent potent correlates of acacia preferred as a host plant by diverse malaria vectors. The results have relevance in the development of odor-bait control strategies including attractive targeted sugar-baits.

Real-time PCR for malaria diagnosis and identification of Plasmodium species in febrile patients in Cubal, Angola.

BACKGROUND: Malaria is the parasitic disease with the highest morbimortality worldwide. The World Health Organization (WHO) estimates that there were approximately 249 million cases in 2022, of which 3.4% were in Angola. Diagnosis is based on parasite identification by microscopy examination, antigen detection, and/or molecular tests, such as polymerase chain reaction (PCR). This study aimed to evaluate the usefulness of real-time PCR as a diagnostic method for malaria in an endemic area (Cubal, Angola). METHODS: A cross-sectional study was carried out at the Hospital Nossa Senhora da Paz in Cubal, Angola, including 200 patients who consulted for febrile syndrome between May and July 2022. From each patient, a capillary blood sample was obtained by finger prick for malaria field diagnosis [microscopy and rapid diagnostic test (RDT)] and venous blood sample for real-time PCR performed at the Hospital Universitario Vall d'Hebron in Barcelona, Spain. Any participant with a positive result from at least one of these three methods was diagnosed with malaria. RESULTS: Of the 200 participants included, 54% were female and the median age was 7 years. Malaria was diagnosed by at least one of the three techniques (microscopy, RDT, and/or real-time PCR) in 58% of the participants, with RDT having the highest percentage of positivity (49%), followed by real-time PCR (39.5%) and microscopy (33.5%). Of the 61 discordant samples, 4 were only positive by microscopy, 13 by real-time PCR, and 26 by RDT. Plasmodium falciparum was the most frequent species detected (90.63%), followed by P. malariae (17.19%) and P. ovale (9.38%). Coinfections were detected in ten participants (15.63%): six (60%) were caused by P. falciparum and P. malariae, three (30%) by P. falciparum and P. ovale, and one (10%) triple infection with these three species. In addition, it was observed that P. falciparum and P. malariae coinfection significantly increased the parasite density of the latter. CONCLUSIONS: RDT was the technique with the highest positivity rate, followed by real-time PCR and microscopy. The results of the real-time PCR may have been underestimated due to suboptimal storage conditions during the transportation of the DNA eluates. However, real-time PCR techniques have an important role in the surveillance of circulating Plasmodium species, given the epidemiological importance of the increase in non-falciparum species in the country, and can provide an estimate of the intensity of infection.

Analysis of care-seeking pathways and factors influencing early and appropriate care-seeking for malaria patients in the Republic of Guinea: a cross-sectional study.

BACKGROUND: Malaria is a major public health issue in Guinea and care-seeking behaviour is dominated by self-medication and delayed access to appropriate care. However early and appropriate care-seeking are essential to control and reduce complicate forms and mortality, particularly for the most vulnerable. This study was conducted to analyse the diagnostic pathway, and the factors associated with early and appropriate care-seeking for malaria patients in the Republic of Guinea. METHODS: A cross-sectional study was carried out between December 2022 to March 2023 in nine health districts within health facilities and at community level. The study population was confirmed malaria patients with RDT or microscopy. Kroeger's conceptual framework was used to design the questionnaire. Conventional recourse was defined as using a healthcare facility or community services, early and appropriate care-seeking was defined as within 24 h of symptom onset in a conventional recourse, and care pathway as the sequence of recourses followed by each patient. Sankey alluvial plots were used to represent patients' diagnostic pathways, and logistic regression to identify factors associated with early and appropriate care-seeking. RESULTS: A total of 3300 malaria patients were studied, of which 1632 (49.45%) were female and 1132 (34.30%) were under 5 years of age, with a median age of 23 months. At the time of the survey, 1337 (40.52%), 1423 (43.12%), and 437 (13.85%) of patients were respectively in their first, second and third recourse. A total of 2002 (60.67%) patients had sought care from a conventional recourse as a first line. Of all patients, 1757 (53.25%) had sought care within 24 h, while 28.55% had sought early and appropriate care. In the initial stages of treatment, self-medication was the most common approach, used by 1214 (37.30%). Patients from the health districts of Boffa (Lower Guinea, coastal region) OR = 0.48 95% CI 0.33-0.70, Dabola (Upper Guinea, savanna region) OR = 0.43 95% CI 0.30-0.63 and Labe (Middle Guinea, mountain region) OR = 0.63 CI 95% 0.43-0.91 (p < 0.05) were more likely to delay appropriate care-seeking, when compared to those in Dixinn, (Conakry). However, the under 5-year-old group OR = 1.55 95% CI 1.30-1.85 (p < 0.001) and the availability of a stable monthly household income OR = 4.98 95% CI 3.03, 8.27 (p < 0.001) were positively associated with early and appropriate care seeking. CONCLUSION: A low rate of early and appropriate care-seeking was observed. Patients sought care through multiple means, often resulting in a delay in adequate management. The results show the need to deploy strategies adapted to the needs of communities.

Potential impact of climatic factors on malaria in Rwanda between 2012 and 2021: a time-series analysis.

BACKGROUND: Malaria remains an important public health problem, particularly in sub-Saharan Africa. In Rwanda, where malaria ranks among the leading causes of mortality and morbidity, disease transmission is influenced by climatic factors. However, there is a paucity of studies investigating the link between climate change and malaria dynamics, which hinders the development of effective national malaria response strategies. Addressing this critical gap, this study analyses how climatic factors influence malaria transmission across Rwanda, thereby informing tailored interventions and enhancing disease management frameworks. METHODS: The study analysed the potential impact of temperature and cumulative rainfall on malaria incidence in Rwanda from 2012 to 2021 using meteorological data from the Rwanda Meteorological Agency and malaria case records from the Rwanda Health Management and Information System. The analysis was performed in two stages. First, district-specific generalized linear models with a quasi-Poisson distribution were applied, which were enhanced by distributed lag non-linear models to explore non-linear and lagged effects. Second, random effects multivariate meta-analysis was employed to pool the estimates and to refine them through best linear unbiased predictions. RESULTS: A 1-month lag with specific temperature and rainfall thresholds influenced malaria incidence across Rwanda. Average temperature of 18.5 °C was associated with higher malaria risk, while temperature above 23.9 °C reduced the risk. Rainfall demonstrated a dual effect on malaria risk: conditions of low (below 73 mm per month) and high (above 223 mm per month) precipitation correlated with lower risk, while moderate rainfall (87 to 223 mm per month) correlated with higher risk. Seasonal patterns showed increased malaria risk during the major rainy season, while the short dry season presented lower risk. CONCLUSION: The study underscores the influence of temperature and rainfall on malaria transmission in Rwanda and calls for tailored interventions that are specific to location and season. The findings are crucial for informing policy that enhance preparedness and contribute to malaria elimination efforts. Future research should explore additional ecological and socioeconomic factors and their differential contribution to malaria transmission.

Global acute malnutrition is associated with geography, season and malaria incidence in the conflict-affected regions of Ouham and Ouham Pendé prefectures, Central African Republic.

BACKGROUND: Ongoing conflict between multiple armed groups, including pastoralist herders in the Central African Republic (CAR) causes frequent population displacements, food insecurity and scarcity of healthcare services. The inaccessibility and insecurity of many areas of CAR limit data collection and assessments from national nutritional surveys. Community health workers (CHWs) trained by an international non-governmental organisation, The MENTOR Initiative, deliver basic healthcare to children under 5 years old living in hard-to-reach and conflict-affected areas in eight subprefectures of north-west CAR. Their nutritional status and its associations with geography, malaria, season and conflict are unknown. METHODS: CHW monthly records (October 2015-August 2021), Armed Conflict Location and Event Data project conflict data and The World Bank Group meteorological data for eight subprefectures of north-west CAR were analysed. Associations between counts of global acute malnutrition (GAM) assessed by mid-upper arm circumference and malaria, season and conflict were investigated using negative binomial regression. RESULTS: Of the 457,325 consultations with children aged 6-59 months, 6.2% and 0.4% were classified as moderately or severely malnourished, respectively. The negative binomial model demonstrated differences in counts of GAM by subprefecture. Counts of GAM were positively associated with the case rate of severe malaria (IRR = 1.045; 95% CI: 1.04-1.06) and the rainy season (July-September) (IRR = 1.10; 95% CI: 1.03-1.17). Conflict events coded as Battles in ACLED were associated with lower counts of GAM (IRR = 0.78; 95% CI: 0.62-0.97). CONCLUSIONS: This analysis shows geographical differences in levels of malnutrition in north-west CAR and demonstrates clear associations between malnutrition, season and malaria. It provides evidence that levels of GAM may be underestimated in north-west CAR in areas experiencing conflict. These findings highlight the need for targeted nutritional support to reach children most at risk of malnutrition. CHWs are a proven effective means of delivering essential primary healthcare services in hard-to-reach, conflict-affected areas.

Evaluating the impact of malaria rapid diagnostic tests on patient-important outcomes in sub-Saharan Africa: a systematic review of study methods to guide effective implementation.

OBJECTIVE: To perform critical methodological assessments on designs, outcomes, quality and implementation limitations of studies evaluating the impact of malaria rapid diagnostic tests (mRDTs) on patient-important outcomes in sub-Saharan Africa. DESIGN: A systematic review of study methods. DATA SOURCES: MEDLINE, EMBASE, Cochrane Library, African Index Medicus and clinical trial registries were searched up to May 2022. ELIGIBILITY CRITERIA: Primary quantitative studies that compared mRDTs to alternative diagnostic tests for malaria on patient-important outcomes within sub-Sahara Africa. DATA EXTRACTION AND SYNTHESIS: Studies were sought by an information specialist and two independent reviewers screened for eligible records and extracted data using a predesigned form using Covidence. Methodological quality was assessed using the National Institutes of Health tools. Descriptive statistics and thematic analysis guided by the Supporting the Use of Research Evidence framework were used for analysis. Findings were presented narratively, graphically and by quality ratings. RESULTS: Our search yielded 4717 studies, of which we included 24 quantitative studies; (15, 62.5%) experimental, (5, 20.8%) quasi-experimental and (4, 16.7%) observational studies. Most studies (17, 70.8%) were conducted within government-owned facilities. Of the 24 included studies, (21, 87.5%) measured the therapeutic impact of mRDTs. Prescription patterns were the most reported outcome (20, 83.3%). Only (13, 54.2%) of all studies reported statistically significant findings, in which (11, 45.8%) demonstrated mRDTs' potential to reduce over-prescription of antimalarials. Most studies (17, 70.8%) were of good methodological quality; however, reporting sample size justification needs improvement. Implementation limitations reported were mostly about health system constraints, the unacceptability of the test by the patients and low trust among health providers. CONCLUSION: Impact evaluations of mRDTs in sub-Saharan Africa are mostly randomised trials measuring mRDTs' effect on therapeutic outcomes in real-life settings. Though their methodological quality remains good, process evaluations can be incorporated to assess how contextual concerns influence their interpretation and implementation. PROSPERO REGISTRATION NUMBER: CRD42018083816.