Clinical evaluation of lateral flow Mologic malaria P.f Ag (LDH) Rapid Diagnostic Test diagnostic accuracy: A cross-sectional study, Sudan 2020-2021

Clinical evaluation of lateral flow Mologic malaria P.f Ag (LDH) Rapid Diagnostic Test diagnostic accuracy: A cross-sectional study, Sudan 2020-2021 | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Clinical evaluation of lateral flow Mologic malaria P.f Ag (LDH) Rapid Diagnostic Test diagnostic accuracy: A cross-sectional study, Sudan 2020-2021 Abdelrahim O. Mohamed, Muzamil M. Abdel Hamid, Arwa Elaagip, Waleed M. A. Jebreel, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7124055/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 29 Oct, 2025 Read the published version in Malaria Journal → Version 1 posted 10 You are reading this latest preprint version Abstract Background Malaria diagnosis by Rapid Diagnostic Test (RDTs) is challenged by the newly emerging histidine-rich protein 2 (HRP2) gene deletion in the Plasmodium falciparum species. The alternative lactate dehydrogenase (LDH)-dependent RDTs suffer from low sensitivity, and improvement in the sensitivity of LDH RDTs is the cornerstone for detecting (HRP2) gene deletion species. This study aimed to evaluate a novel improved Mologic LDH-dependent RDT for the diagnosis of P. falciparum malaria in partnership with FIND, Switzerland. Methods This is a descriptive cross-sectional study evaluating the clinical performance of improved Mologic P. falciparum LDH RDTs in two rural sites in Khartoum state, Sudan. Five hundred patients presenting with symptoms suggestive of malaria in the two primary care health centers were included after signing an informed consent. On-site microscopy screening, resulting in positive P. falciparum parasites or negative results, was included. Exclusion criteria included children under 5 years old, microscopy-positive P. vivax malaria, and severely ill patients. Finger-prick blood was collected for examination with microscopy, the index Mologic RDT, the comparator RDT, and preparation of DBS blood for nested PCR. Nested PCR was used as a reference method. The tests of microscopy and RDTs were performed by different lab personnel, blinded to each other's results. Results The mean age of the study subjects was 31 years, ranging from 5 to 80 years. Out of 500 patients, 210 were positive by PCR, 200 by expert microscopy, 193 by index Mologic RDT, and 199 by comparator RDT. The sensitivities of microscopy, index RDT, and comparator RDT were 95.24% (95% CI, 91.4–97.6), 91.9% (95% CI, 87.3–95.2), and 93.81% (95% CI, 89.6–96.6), respectively. All tests were nearly 100% specific for the detection of P. falciparum parasites. The concordance test (κ) showed more than 0.929 for all the tests. Seven samples were P. falciparum HRP2 Ag negative and were detected by Mologic RDT. Conclusions The novel Mologic P f LDH RDT showed performance concordant with standard expert microscopy and the comparator P f HRP2 Ag RDT. The lower sensitivity of the Mologic P f RDT, although not significant, makes it suitable for the clinical management of P. falciparum HRP2-negative malaria. Clinical evaluation lateral flow Rapid Diagnostic Test diagnostic accuracy malaria field testing Plasmodium falciparum Sudan Background Malaria remains a life-threatening parasitic disease affecting millions globally. According to the WHO, there were an estimated 263 million cases of malaria in 2023, an additional 11 million cases compared to 2022, and two-thirds of all mortality occurred in the under-5-year-olds [ 1 ]. Sudan is a conflict-laden country that has recently adopted the high-burden impact approach to strengthen the control of malaria. In 2020, Sudan had the heaviest burden of malaria in the Eastern Mediterranean Region, with the disease accounting for 56% of the cases and 61% of the deaths. The post-Millennium Development Goals Project era was marked by a drastic ~ 40% increase in malaria cases in Sudan [ 2 ]. In 2021, 3.7 million cases of malaria were reported, 1760 of whom succumbed to the disease [ 3 , 4 ]. This highlights challenges in prevention and control, including climate change, funding gaps, conflicts, drug and insecticide resistance, and Plasmodium falciparum histidine-rich protein-2 gene-deleted parasites (P f HRP2 gene-deleted parasites) [ 5 – 7 ]. Light microscopy forms the cornerstone of malaria case management; however, its operational challenges paved the way for rapid diagnostic tests (RDTs) to support diagnosis in situations where microscopy is impractical. Plasmodium falciparum HRP2 RDTs form the bulk of malaria case management in many resource-limited settings [ 8 ]. While RDTs are fast, sensitive, and simple to use, the growing circulation of HRP2-deleted parasites has raised concerns about malaria control and prevention due to false negative diagnoses. Plasmodial lactate dehydrogenase (pLDH) is increasingly becoming an optimal biomarker for the diagnosis of malaria owing to threats of P f HRP2 gene-deleted parasites; however, it is hampered by low sensitivity [ 9 ]. A few studies have confirmed that LDH lateral flow assays can perform as well as standard-of-care RDTs if improved [ 10 ]. The Mologic RDT is a novel prototype LDH-based lateral flow assay designed to be highly sensitive, and its potential low cost could expand accessibility of the test to vast resource-constrained settings. However, there is currently no data to support its performance in a clinical testing environment. This study aimed to evaluate the clinical performance of a novel Mologic LDH-dependent RDT diagnostic test for P. falciparum malaria endemic areas with reported HRP2 gene deletion parasites. Methods Study design and study sites This was a descriptive cross-sectional study aimed at assessing the performance of the novel Mologic P f LDH Ag RDTs in detecting the falciparum malaria parasite. Two primary health care centers, Gezira Slanj (GS) and Alsororab (SOR), 40 and 50 km from rural Omdurman, North Khartoum, respectively, were used to recruit the study subjects between December 2020 and February 2021. Both sites are endemic for P. falciparum and P. vivax malaria, with seasonal transmission [ 11 ]. Study subjects and Inclusion criteria Patients with symptoms suggestive of malaria who were at least 5 years of age were requested to participate in the study. All participants who agreed to participate were asked to sign an informed consent. Adults and guardians of children were asked to sign informed consent forms. Children aged 12 years and above were also asked to sign an assent form. Subjects diagnosed by expert microscopy with P. vivax infection were excluded. Following WHO guidelines, patients with severe diseases, those who had received malaria treatment within the last four weeks, and children under 5 years of age were excluded from this study [ 12 ]. Sample collection A total of 75 µL of a finger-prick blood sample was collected by trained laboratory personnel from each patient. Fifteen µL was used to prepare two thick and two thin smears, 5 µL each for Mologic and SD Bioline RDTs. Fifty µL was used to prepare 2 dried blood spots (DBS) protein saver cards for molecular analysis. Light microscopy Blood smears were allowed to air dry, then stained with 3% Giemsa (RAL Diagnostics, France) and examined within an hour by trained microscopists in the two hospitals for malaria parasite detection and species identification. Parasite densities were estimated by counting the number of asexual parasites per 200 leukocytes or 500 leukocytes; if the count was less than 10 asexual parasites per 200 leukocytes, a normal leukocyte count of 8,000/µL was assumed [ 13 ]. Verification of microscopic slide readings and quantification of malaria parasites was performed by WHO-certified expert microscopists at the Institute of Endemic Diseases (IEND), University of Khartoum. Discordance between the site microscopist and the expert microscopist was resolved by a third reader using the Obare method calculator [ 14 ]. Index and Comparator Rapid Diagnostic Tests Mologic CARD Malaria P f (LDH) RDT (Mologic inc,UK) (index test) is a qualitative lateral flow immunochromatography test. The SD Bioline CARD Malaria HRP2 (P f ) and pLDH (P. v ) Antigen Rapid Test device (SD Bioline RDT) (comparator test) contains a membrane strip, which is coated with a monoclonal antibody and another monoclonal antibody as two separate lines across a test strip. Testing was performed following the manufacturer's instructions. Two laboratory technicians read the test independently and were blinded to each other's readings, including the microscopy results. DNA extraction and nested PCR DNA was extracted from a half circle of a dried blood spot using a QIAamp DNA extraction kit following the manufacturer's instructions (QIAGEN # 51306, Netherlands). Nested PCR was performed targeting the 18S rRNA gene according to the protocol of [ 15 ]. Outer PCR was performed in a 25 µL reaction consisting of outer genus-specific primers—fPLU5/rPLU6. An inner PCR reaction, consisting of species-specific primers, was performed in a 25 µL reaction. PCR products were visualized on a 1.5% agarose gel under UV transillumination using BDA gel image documentation system (Biometra Analytika Jena Company, Germany). A positive reaction yielded a fragment of ~ 205 bp for P. falciparum parasites and ~ 100 bp for P. vivax . Each assay included a no-template control, a negative control, and a positive control. Ethical consideration This Research initially received approval from the institutional committee of the Institute of Endemic Diseases. Then the study obtained ethical approvals from the ethical committee of the Medical and Health Sciences, University of Khartoum (REF: FM/DO/EC, Date: 22/01/2020) and the Federal Ministry of Health's National Ethical Committee (REF NO: FMoH/ERC, Date: 15/09/2020). All participants or guardians of minor patients signed written informed consent (or assent when applicable). According to Sudan's National Guidelines, all Plasmodium -infected participants received antimalarial treatment [ 16 ]. Statistical analysis Demographic and clinical data, including age, gender, and clinical presentation, were entered into OpenClinica, which is a platform used by EDC, Needham, USA and is externally monitored by FIND, Switzerland. Diagnostic performance and statistical analysis were performed using IBM SPSS Statistics version 21.0 (Statistical Package for the Social Sciences), MedCalc® statistical software (MedCalc Software Ltd, Ostend, Belgium), and RStudio (version 4.4.1), an integrated development environment for R. Sensitivity, specificity, positive and negative predictive values were calculated using the standard formula from MedCalc, and 95% confidence interval (CI) was calculated using Wilson’s score method (a statistical technique used to estimate the confidence interval for a population proportion based on the binomial distribution) in comparison to the reference method). Concordance of the index and comparator tests with the reference was assessed using Cohen’s kappa agreement test, to measure the level of agreement between two raters or diagnostic methods, beyond what would be expected by chance. It quantifies inter-rater reliability for categorical variables. RStudio 4.4.1 was used to calculate the Area Under the Curve (AUC) to evaluate the overall diagnostic performance of the test. AUC refers to operating characteristic (ROC) curve and reflects the test's ability to distinguish between positive and negative cases. Results Demographic and parasitological characteristics of study subjects Table (1) presents the characteristics of 500 patients with symptoms of malaria enrolled in this study. The mean age of the subjects was 31 years, ranging from 5 to 80 years. There were 262 male subjects and 238 female subjects. Eighty-three percent (415) of the participants were adults. Patients presenting with temperature ≥ 37.5 comprised 49.6% of the patients. Fever was the main presenting symptom among the patients (492), with other symptoms including headache, fatigue, and nausea presenting as Suppl. Table 1. Microscopic examination showed that 200 subjects were positive for P. falciparum malaria and 300 were negative. The geometric mean of the parasite density was 7161 parasites/µL, with a standard error of ± 809, and a range of parasitemia of 80–162,000 parasites/µL. Nested PCR yielded 210 positives, of which 206 were P. falciparum monoinfections, and 4 were P. falciparum / P. vivax mixed infections. The index Mologic P f Ag RDT was positive in 193 samples, and the comparator SD Bioline P f Ag was positive in 199 patients (Table 1 ). All positive samples by PCR and microscopy were confirmed as P. falciparum infections. Seven HRP2 Ag-negative samples were found to be positive by Mologic and PCR. Six of these samples were also positive by microscopy (Suppl. File 1). Table 1 Demographic and parasitological characteristics of the study participants Characteristic Description N (%) Study Site Alsororab 323 (64.6) Gezira Slanj 177 (35.4) 18 415 (83) Fever < 37.5 252 (50.4) ≥ 37.5 248 (49.6) Gender Female 238 (47.6) Male 262 (52.4) Expert Microscopy Negative 300 (60) Positive* 200 (40) Parasite density (parasites/µl) 10,000 92 (42.3) Nested PCR Negative 290 (58) P.f 206 (41.2) P.f/P.v 4 (0.8) Mologic P f Ag RDT Negative 307 (61.4) Positive 193 (38.6) SD Bioline P f /P.v Ag RDT Negative 301 (60.2) P.f 198 (39.8) P.f/P.v 1 (0.2) *= P.f Diagnostic Performance of Mologic P.f Ag and the Comparator Test compared to the reference test Table (2) shows the sensitivity, specificity, and accuracy of Mologic, SD Bioline, and microscopy compared to the nested PCR reference method. Mologic RDT showed a sensitivity of 91% (95% CI 87.3–95.2), 100% (95% CI 98.7–100) specificity, and accuracy of 96% (95% CI 94.1–97.6). Comparator SD Bioline showed sensitivity of 93.8% (95% CI 89.6–96.6), specificity of 99% (95% CI 97.5–99.9), and accuracy of 97.7% (95% CI 94.7–98.1). While the expert microscopic examination showed sensitivity of 95% (95% CI 91.4–97.6), specificity of 100% (95% CI 98.7–100), and accuracy of 96.7% (95% CI 96.0-98.8). The positive and negative predictive values are also provided in (Table 2 ). Concordance of the index and the comparator tests with the reference Nested PCR The weighted Cohen Kappa agreement testing values (κ) and 95% confidence intervals (CI) were 0.929 (0.896–0.962), 0.938 (0.907–0.968), and 0.959 (0.933–0.984) for Mologic P f Ag RDT, SD Bioline P f RDT, and expert microscopy, respectively. Figure (1) illustrates the Receiver Operating Characteristic Curve, which compares the diagnostic performance of three malaria diagnostic methods, expert microscopy, RDT (SD Bioline), and RDT (Mologic) with the reference line representing a random classifier. Discussion Rapid diagnostic tests have revitalized the global malaria elimination agenda by offering simple-to-use, quick, and yet accurate test options that are amenable to resource-constrained settings. This descriptive study was designed to assess the performance of a novel improved P. falciparum LDH (Mologic P f Ag card) for diagnosing falciparum malaria in areas of HRP2 deletion threads. The sensitivity, specificity, and accuracy of Mologic RDT have revealed that its performance, though seemingly less than other comparators, was not significantly different from them. It has been reported earlier that LDH-dependent RDTs have lower sensitivity [ 17 , 18 ]. This novel product has shown that improved LDH-dependent RDT sensitivity can be achieved to bridge the gap created by HRP2 deletion. HRP2 gene deletion, a newly emerging threat to an important diagnostic tool, is reported in Ethiopia, Peru, and Sudan and seems to be progressive, so the introduction of improved LDH RDTs is required and timely [ 19 – 21 ]. The novel Mologic RDT showed slightly less sensitivity than HRP2-based SD Bioline RDT and expert microscopy. However, it demonstrated complete concordance with expert microscopy in avoiding false-positive results compared to the reference PCR, resulting in a specificity of 100%. The HRP2 antigen-dependent RDTs in this study showed high sensitivity comparable with expert microscopy, despite seven samples not being detected by this RDT. This implies the need for a supplementary RDT, such as Mologic, to diagnose those cases suspected of HRP2 gene deletion. This gene deletion is evident because these samples were detected by PCR, Mologic, and expert microscopy. The emergence of HRP2 deletion is becoming a reality in malaria-endemic areas, necessitating the introduction of novel diagnostic tools to help manage patients harboring this gene [ 22 – 24 ]. This study showed that LDH Mologic's low sensitivity is mostly in the lower parasite count profile, probably making it unfavorable for elimination screening and only suited for symptomatic clinical management. Eliminating malaria is a global target within the Sustainable Development Goals, and countries should be able to detect both symptomatic and low parasitemia in their endeavors to eliminate malaria [ 22 ]. Concordance and the area under the curve have demonstrated that Mologic is a well-suited diagnostic rapid tool for managing P. falciparum malaria. Conclusion In conclusion, Mologic LDH-based RDTs have demonstrated performance comparable to that of the standard expert microscopic examination and the in-use HRP2 antigen-dependent RDT. Mologic can help detect parasites harboring an emerging HRP2 gene deletion. Abbreviations WHO: World Health Organization RDT: Rapid Diagnostic Test MOH: Ministry of Health HRP2: Histidine-rich Protein-2 IEND: Institute of Endemic Diseases, University of Khartoum, Sudan PCR: polymerase chain reaction pLDH: Plasmodial lactate dehydrogenase CI: confidence interval ROC: Receiver Operating Characteristic AUC: Area Under Curve DBS: dried blood spots FIND: global alliance for diagnostics GS: Gezira Slanj SOR: Alsororab Declarations Ethics approval and consent to participate This study protocol was reviewed and received ethical approval from the National Ethics Committee, Federal Ministry of Health, Sudan (REF NO: FMoH/ERC, Date: 15/09/2020), and the Medical and Health Sciences Ethical Committee, University of Khartoum (REF: FM/DO/EC, Date: 22/01/2020). Informed written consent was obtained from all participants aged 18 years or older. For children aged 5 years and older but younger than 13 years, consent was sought from their parents or legal guardians. For children aged 13 years and older but younger than 18 years, assent from the child and consent of the parent or legal guardian were obtained. Consent for publication Not applicable. Availability of data and materials The datasets used and analysed during the current study are available from the corresponding author upon reasonable request. Competing interests The authors declare that they have no competing interests. Funding The Australian Government funded this study, Department for Foreign Affairs and Trade, as part of the FIND Malaria Innovation Platform Project. Authors’ contributions MMA, SD, AOM: proposal development, study design, and implementation of research. AOM: supervision of medical officers and sample collection. AOM, MMA, WMA, MC: Data analysis and interpretation, draft preparation, critical appraisal, and revision of the final manuscript. FOM, AE, and MMA: Sample collection, data entry, and PCR test performance. WMA, SBA, SAM, and MC: Data curation and analysis. SAM and TE: Expert microscopy examination. MMA, AOM, WMA, AE, and MC: reviewed the manuscript. All authors read and approved of the final manuscript. Acknowledgments The authors thank the directors and all staff at the two hospitals in GS and SOR for their assistance and collaboration in patient recruitment and performing on-site microscopy. Also, we would like to thank the WHO Malaria NAAT EQA (External Quality Assessment) scheme for providing malaria positive DNA samples for the PCR assays. Authors’ details Abdelrahim O. Mohamed 1,2 , Muzamil M. Abdel Hamid 1* , Waleed M. A. Jebreel 1 , Martin Chamai 3 , Shaden B. A. Ahmed 1, Fayad Osman Mohammed 1 , Arwa Elaagip 1 , Musab M. Albsheer 1,4 , Sabine Dittrich 5 , Sayed A. Mustafa 6 , Tarig Elfaki 6 , Xavier Ding 5,7 . 1 Department of Parasitology and Medical Entomology, Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan. 2 Department of Biochemistry, Faculty of Medicine, University of Khartoum, Khartoum, Sudan. 3 West Africa Centre for Cell and Molecular Biology of Infectious Pathogens, University of Ghana, LG, Accra, Ghana. 4 Faculty of Medical Laboratory Sciences, Sinnar University, Sinnar, Sudan. 5 FIND, Geneva, Switzerland. 6 Malaria Control Program, Federal Ministry of Health, Khartoum, Sudan. 7 . References World Health Organization . World malaria report 2024. Geneva: World Health Organization; 2024. World Health Organization. World malaria report 2022. Geneva: World Health Organization; 2022 World Health Organization. World malaria report 2023. Geneva: World Health Organization; 2023. Federal Ministry of Health—Sudan. Malaria program review, 2023. National Malaria Control Program; 2023. 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Aptamers as innovative tools for malaria diagnosis and treatment: advances and future perspectives. Biology Methods and Protocols. 2025;10(1):bpaf025. Bachman C, Cate D, Grant B, Boyce M, Lemoine J, Bondzie E, et al. A novel malaria lateral flow assay for detecting Plasmodium falciparum lactate dehydrogenase in Busia, Uganda. Am J Trop Med Hyg. 2022;106(3):850-852. Abdelwhab O, Elaagip A, Albsheer M, Ahmed A, Paganotti G, Abdel Hamid M. Molecular and morphological identification of suspected Plasmodium vivax vectors in Central and Eastern Sudan. Malar J. 2021;20:1-7. World Health Organization. WHO technical consultation on preferred product characteristics for drugs used in malaria chemoprevention: meeting report, 15–16 December 2020. World Health Organization; 2022 Oct 14. World Health Organization. Basic malaria microscopy: Part I. Learner’s guide. 2nd ed. Geneva: World Health Organization; 2010. Torres K, Bachman C, Delahunt C, Alarcon Baldeon J, Alava F, Gamboa Vilela D, et al. Automated microscopy for routine malaria diagnosis: a field comparison on Giemsa-stained blood films in Peru. Malar J. 2018;17(1):339. Snounou G, Singh B. Nested PCR analysis of Plasmodium parasites. Methods Mol Med. 2002;72:189-203. Elhassan S, Mohamed S, Alnaeem K, Noureddin A, Abass S, Saad F. Technical Advisory Committee. Adapted guidelines for malaria case management in Sudan. Sudan Journal of Medical Sciences. 2024;19(4):531-546. Coldiron M, Assao B, Langendorf C, Sayinzoga-Makombe N, Ciglenecki I, de La Tour R, et al. Clinical diagnostic evaluation of HRP2 and pLDH-based rapid diagnostic tests for malaria in an area receiving seasonal malaria chemoprevention in Niger. Malar J. 2019;18(1):443. Mukkala A, Kwan J, Lau R, Harris D, Kain D, Boggild A. An update on malaria rapid diagnostic tests. Current infectious disease reports. 2018;20:1-8. Mekonen B, Dugassa S, Feleke S, Dufera B, Gidisa B, Adamu A, et al . Widespread pfhrp2/3 deletions and HRP2-based false-negative results in southern Ethiopia. Malar J. 2024;23(1):108. Fontecha G, Mejía R, Banegas E, Ade M, Mendoza L, Ortiz B, et al . Deletions of pfhrp2 and pfhrp3 genes of Plasmodium falciparum from Honduras, Guatemala and Nicaragua. Malar J. 2018;17(1):320. Boush M, Djibrine M, Mussa A, Talib M, Maki A, Mohammed A, et al . Plasmodium falciparum isolate with histidine-rich protein 2 gene deletion from Nyala City, Western Sudan. Scientific Reports. 2020;10(1):12822. Hamid M, Mohamed A, Mohammed F, Elaagip A, Mustafa S, Elfaki T, et al . Diagnostic accuracy of an automated microscope solution (miLab™) in detecting malaria parasites in symptomatic patients at point-of-care in Sudan: a case–control study. Malar J. 2024;23(1):200. Yu H, Mohammed F, Abdel Hamid M, Yang F, Kassim Y, Mohamed A, et al . Patient-level performance evaluation of a smartphone-based malaria diagnostic application. Malar J. 2023;22(1):33. Oyegoke O, Maharaj L, Akoniyon O, Kwoji I, Roux A, Adewumi T, et al . Malaria diagnostic methods with the elimination goal in view. Parasitology research. 2022;121(7):1867-1885. Table 2 Table 2 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table2.docx SupplFigureandTable.docx EvaluationofPfLDHbasedmologicRDTcardrawdata.xlsx MologicPfAgRDTStudySudanpatientssymptomsSHEET.xlsx Cite Share Download PDF Status: Published Journal Publication published 29 Oct, 2025 Read the published version in Malaria Journal → Version 1 posted Editorial decision: Revision requested 21 Aug, 2025 Reviews received at journal 14 Aug, 2025 Reviews received at journal 14 Aug, 2025 Reviewers agreed at journal 10 Aug, 2025 Reviewers agreed at journal 09 Aug, 2025 Reviewers agreed at journal 28 Jul, 2025 Reviewers invited by journal 28 Jul, 2025 Editor assigned by journal 16 Jul, 2025 Submission checks completed at journal 16 Jul, 2025 First submitted to journal 14 Jul, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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A.","lastName":"Ahmed","suffix":""},{"id":491709603,"identity":"1eff5174-3584-4315-bfad-c59243b36849","order_by":9,"name":"Martin Chamai","email":"","orcid":"","institution":"University of Ghana","correspondingAuthor":false,"prefix":"","firstName":"Martin","middleName":"","lastName":"Chamai","suffix":""},{"id":491709604,"identity":"f67cb9b5-b277-4973-aab2-fdf5e873d692","order_by":10,"name":"Sabine Dittrich","email":"","orcid":"","institution":"FIND","correspondingAuthor":false,"prefix":"","firstName":"Sabine","middleName":"","lastName":"Dittrich","suffix":""}],"badges":[],"createdAt":"2025-07-14 19:23:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7124055/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7124055/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12936-025-05609-x","type":"published","date":"2025-10-29T15:58:11+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":95040010,"identity":"cd874345-a62c-4c22-a768-d43e43eb0e8d","added_by":"auto","created_at":"2025-11-03 16:07:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":785489,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7124055/v1/dfeb0081-b984-45f8-b30a-88d3437d1fb5.pdf"},{"id":87868438,"identity":"84dba54a-14b2-4307-b00d-2c9eb8ac163f","added_by":"auto","created_at":"2025-07-29 21:28:45","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":17135,"visible":true,"origin":"","legend":"","description":"","filename":"Table2.docx","url":"https://assets-eu.researchsquare.com/files/rs-7124055/v1/b54a8ea4b3b05713e54bc24a.docx"},{"id":87868609,"identity":"18016d2b-8c72-495f-8cbe-c9c26e678d03","added_by":"auto","created_at":"2025-07-29 21:36:45","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":71796,"visible":true,"origin":"","legend":"","description":"","filename":"SupplFigureandTable.docx","url":"https://assets-eu.researchsquare.com/files/rs-7124055/v1/79bb05f3c07bb9cc032dd0bc.docx"},{"id":87868873,"identity":"1571827a-ba93-4ed3-9d4d-3f19de4c5b5e","added_by":"auto","created_at":"2025-07-29 21:44:45","extension":"xlsx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":35404,"visible":true,"origin":"","legend":"","description":"","filename":"EvaluationofPfLDHbasedmologicRDTcardrawdata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-7124055/v1/e01e14d3066f3adb51de1e07.xlsx"},{"id":87868448,"identity":"ea6e9b93-a237-4a70-bc2c-dccd57ba47d9","added_by":"auto","created_at":"2025-07-29 21:28:45","extension":"xlsx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":43075,"visible":true,"origin":"","legend":"","description":"","filename":"MologicPfAgRDTStudySudanpatientssymptomsSHEET.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-7124055/v1/7cd3167106068bd089104211.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eClinical evaluation of lateral flow Mologic malaria \u003cem\u003eP.f \u003c/em\u003eAg (LDH) Rapid Diagnostic Test diagnostic accuracy: A cross-sectional study, Sudan 2020-2021\u003c/p\u003e","fulltext":[{"header":"Background","content":"\u003cp\u003eMalaria remains a life-threatening parasitic disease affecting millions globally. According to the WHO, there were an estimated 263\u0026nbsp;million cases of malaria in 2023, an additional 11\u0026nbsp;million cases compared to 2022, and two-thirds of all mortality occurred in the under-5-year-olds [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Sudan is a conflict-laden country that has recently adopted the high-burden impact approach to strengthen the control of malaria. In 2020, Sudan had the heaviest burden of malaria in the Eastern Mediterranean Region, with the disease accounting for 56% of the cases and 61% of the deaths. The post-Millennium Development Goals Project era was marked by a drastic ~ 40% increase in malaria cases in Sudan [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. In 2021, 3.7\u0026nbsp;million cases of malaria were reported, 1760 of whom succumbed to the disease [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. This highlights challenges in prevention and control, including climate change, funding gaps, conflicts, drug and insecticide resistance, and \u003cem\u003ePlasmodium falciparum\u003c/em\u003e histidine-rich protein-2 gene-deleted parasites (P\u003cem\u003ef\u003c/em\u003eHRP2 gene-deleted parasites) [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e–\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eLight microscopy forms the cornerstone of malaria case management; however, its operational challenges paved the way for rapid diagnostic tests (RDTs) to support diagnosis in situations where microscopy is impractical. \u003cem\u003ePlasmodium falciparum\u003c/em\u003e HRP2 RDTs form the bulk of malaria case management in many resource-limited settings [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. While RDTs are fast, sensitive, and simple to use, the growing circulation of HRP2-deleted parasites has raised concerns about malaria control and prevention due to false negative diagnoses. \u003cem\u003ePlasmodial\u003c/em\u003e lactate dehydrogenase (pLDH) is increasingly becoming an optimal biomarker for the diagnosis of malaria owing to threats of P\u003cem\u003ef\u003c/em\u003eHRP2 gene-deleted parasites; however, it is hampered by low sensitivity [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eA few studies have confirmed that LDH lateral flow assays can perform as well as standard-of-care RDTs if improved [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The Mologic RDT is a novel prototype LDH-based lateral flow assay designed to be highly sensitive, and its potential low cost could expand accessibility of the test to vast resource-constrained settings. However, there is currently no data to support its performance in a clinical testing environment. This study aimed to evaluate the clinical performance of a novel Mologic LDH-dependent RDT diagnostic test for \u003cem\u003eP. falciparum\u003c/em\u003e malaria endemic areas with reported HRP2 gene deletion parasites.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cb\u003eStudy design and study sites\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThis was a descriptive cross-sectional study aimed at assessing the performance of the novel Mologic P\u003cem\u003ef\u003c/em\u003e LDH Ag RDTs in detecting the \u003cem\u003efalciparum\u003c/em\u003e malaria parasite. Two primary health care centers, Gezira Slanj (GS) and Alsororab (SOR), 40 and 50 km from rural Omdurman, North Khartoum, respectively, were used to recruit the study subjects between December 2020 and February 2021. Both sites are endemic for \u003cem\u003eP. falciparum\u003c/em\u003e and \u003cem\u003eP. vivax\u003c/em\u003e malaria, with seasonal transmission [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cb\u003eStudy subjects and Inclusion criteria\u003c/b\u003e\u003c/p\u003e\u003cp\u003ePatients with symptoms suggestive of malaria who were at least 5 years of age were requested to participate in the study. All participants who agreed to participate were asked to sign an informed consent. Adults and guardians of children were asked to sign informed consent forms. Children aged 12 years and above were also asked to sign an assent form. Subjects diagnosed by expert microscopy with \u003cem\u003eP. vivax\u003c/em\u003e infection were excluded. Following WHO guidelines, patients with severe diseases, those who had received malaria treatment within the last four weeks, and children under 5 years of age were excluded from this study [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cb\u003eSample collection\u003c/b\u003e\u003c/p\u003e\u003cp\u003eA total of 75 µL of a finger-prick blood sample was collected by trained laboratory personnel from each patient. Fifteen µL was used to prepare two thick and two thin smears, 5 µL each for Mologic and SD Bioline RDTs. Fifty µL was used to prepare 2 dried blood spots (DBS) protein saver cards for molecular analysis.\u003c/p\u003e\u003cp\u003e\u003cb\u003eLight microscopy\u003c/b\u003e\u003c/p\u003e\u003cp\u003eBlood smears were allowed to air dry, then stained with 3% Giemsa (RAL Diagnostics, France) and examined within an hour by trained microscopists in the two hospitals for malaria parasite detection and species identification. Parasite densities were estimated by counting the number of asexual parasites per 200 leukocytes or 500 leukocytes; if the count was less than 10 asexual parasites per 200 leukocytes, a normal leukocyte count of 8,000/µL was assumed [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Verification of microscopic slide readings and quantification of malaria parasites was performed by WHO-certified expert microscopists at the Institute of Endemic Diseases (IEND), University of Khartoum. Discordance between the site microscopist and the expert microscopist was resolved by a third reader using the Obare method calculator [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cb\u003eIndex and Comparator Rapid Diagnostic Tests\u003c/b\u003e\u003c/p\u003e\u003cp\u003eMologic CARD Malaria P\u003cem\u003ef\u003c/em\u003e (LDH) RDT (Mologic inc,UK) (index test) is a qualitative lateral flow immunochromatography test. The SD Bioline CARD Malaria HRP2 (P\u003cem\u003ef\u003c/em\u003e) and pLDH (P.\u003cem\u003ev\u003c/em\u003e) Antigen Rapid Test device (SD Bioline RDT) (comparator test) contains a membrane strip, which is coated with a monoclonal antibody and another monoclonal antibody as two separate lines across a test strip. Testing was performed following the manufacturer's instructions. Two laboratory technicians read the test independently and were blinded to each other's readings, including the microscopy results.\u003c/p\u003e\u003cp\u003e\u003cb\u003eDNA extraction and nested PCR\u003c/b\u003e\u003c/p\u003e\u003cp\u003eDNA was extracted from a half circle of a dried blood spot using a QIAamp DNA extraction kit following the manufacturer's instructions (QIAGEN # 51306, Netherlands). Nested PCR was performed targeting the 18S rRNA gene according to the protocol of [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Outer PCR was performed in a 25 µL reaction consisting of outer genus-specific primers—fPLU5/rPLU6. An inner PCR reaction, consisting of species-specific primers, was performed in a 25 µL reaction. PCR products were visualized on a 1.5% agarose gel under UV transillumination using BDA gel image documentation system (Biometra Analytika Jena Company, Germany).\u003c/p\u003e\u003cp\u003eA positive reaction yielded a fragment of ~ 205 bp for \u003cem\u003eP. falciparum\u003c/em\u003e parasites and ~ 100 bp for \u003cem\u003eP. vivax\u003c/em\u003e. Each assay included a no-template control, a negative control, and a positive control.\u003c/p\u003e\u003cp\u003e\u003cb\u003eEthical consideration\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThis Research initially received approval from the institutional committee of the Institute of Endemic Diseases. Then the study obtained ethical approvals from the ethical committee of the Medical and Health Sciences, University of Khartoum (REF: FM/DO/EC, Date: 22/01/2020) and the Federal Ministry of Health's National Ethical Committee (REF NO: FMoH/ERC, Date: 15/09/2020). All participants or guardians of minor patients signed written informed consent (or assent when applicable). According to Sudan's National Guidelines, all \u003cem\u003ePlasmodium\u003c/em\u003e-infected participants received antimalarial treatment [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eDemographic and clinical data, including age, gender, and clinical presentation, were entered into OpenClinica, which is a platform used by EDC, Needham, USA and is externally monitored by FIND, Switzerland. Diagnostic performance and statistical analysis were performed using IBM SPSS Statistics version 21.0 (Statistical Package for the Social Sciences), MedCalc® statistical software (MedCalc Software Ltd, Ostend, Belgium), and RStudio (version 4.4.1), an integrated development environment for R. Sensitivity, specificity, positive and negative predictive values were calculated using the standard formula from MedCalc, and 95% confidence interval (CI) was calculated using Wilson’s score method (a statistical technique used to estimate the confidence interval for a population proportion based on the binomial distribution) in comparison to the reference method). Concordance of the index and comparator tests with the reference was assessed using Cohen’s kappa agreement test, to measure the level of agreement between two raters or diagnostic methods, beyond what would be expected by chance. It quantifies inter-rater reliability for categorical variables. RStudio 4.4.1 was used to calculate the Area Under the Curve (AUC) to evaluate the overall diagnostic performance of the test. AUC refers to operating characteristic (ROC) curve and reflects the test's ability to distinguish between positive and negative cases.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eDemographic and parasitological characteristics of study subjects\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTable (1) presents the characteristics of 500 patients with symptoms of malaria enrolled in this study. The mean age of the subjects was 31 years, ranging from 5 to 80 years. There were 262 male subjects and 238 female subjects. Eighty-three percent (415) of the participants were adults. Patients presenting with temperature\u0026thinsp;\u0026ge;\u0026thinsp;37.5 comprised 49.6% of the patients. Fever was the main presenting symptom among the patients (492), with other symptoms including headache, fatigue, and nausea presenting as Suppl. Table 1. Microscopic examination showed that 200 subjects were positive for \u003cem\u003eP. falciparum\u003c/em\u003e malaria and 300 were negative. The geometric mean of the parasite density was 7161 parasites/\u0026micro;L, with a standard error of \u0026plusmn;\u0026thinsp;809, and a range of parasitemia of 80\u0026ndash;162,000 parasites/\u0026micro;L.\u003c/p\u003e\n\u003cp\u003eNested PCR yielded 210 positives, of which 206 were \u003cem\u003eP. falciparum\u003c/em\u003e monoinfections, and 4 were \u003cem\u003eP. falciparum\u003c/em\u003e/\u003cem\u003eP. vivax\u003c/em\u003e mixed infections. The index Mologic P\u003cem\u003ef\u003c/em\u003e Ag RDT was positive in 193 samples, and the comparator SD Bioline P\u003cem\u003ef\u003c/em\u003e Ag was positive in 199 patients (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). All positive samples by PCR and microscopy were confirmed as \u003cem\u003eP. falciparum\u003c/em\u003e infections.\u003c/p\u003e\n\u003cp\u003eSeven HRP2 Ag-negative samples were found to be positive by Mologic and PCR. Six of these samples were also positive by microscopy (Suppl. File 1).\u003c/p\u003e\n\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eDemographic and parasitological characteristics of the study participants\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCharacteristic\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDescription\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eN (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eStudy Site\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAlsororab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e323 (64.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGezira Slanj\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e177 (35.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29 (5.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge group\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10\u0026ndash;18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e56 (11.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026gt;\u0026thinsp;18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e415 (83)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eFever\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;37.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e252 (50.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ge;\u0026thinsp;37.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e248 (49.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e238 (47.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e262 (52.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eExpert Microscopy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e300 (60)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePositive*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e200 (40)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eParasite density (parasites/\u0026micro;l)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;1000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21 (10.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1000\u0026ndash;10,000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e81 (41.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026gt;\u0026thinsp;10,000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e92\u0026nbsp;(42.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eNested PCR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e290 (58)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP.f\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e206 (41.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP.f/P.v\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4 (0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eMologic P\u003cem\u003ef\u003c/em\u003e Ag RDT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e307 (61.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePositive\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e193 (38.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eSD Bioline P\u003cem\u003ef\u003c/em\u003e/P.v Ag RDT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e301 (60.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP.f\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e198 (39.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP.f/P.v\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"3\"\u003e*= P.f\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eDiagnostic Performance of Mologic\u003c/strong\u003e \u003cstrong\u003eP.f\u003c/strong\u003e \u003cstrong\u003eAg and the Comparator Test compared to the reference test\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTable (2) shows the sensitivity, specificity, and accuracy of Mologic, SD Bioline, and microscopy compared to the nested PCR reference method. Mologic RDT showed a sensitivity of 91% (95% CI 87.3\u0026ndash;95.2), 100% (95% CI 98.7\u0026ndash;100) specificity, and accuracy of 96% (95% CI 94.1\u0026ndash;97.6). Comparator SD Bioline showed sensitivity of 93.8% (95% CI 89.6\u0026ndash;96.6), specificity of 99% (95% CI 97.5\u0026ndash;99.9), and accuracy of 97.7% (95% CI 94.7\u0026ndash;98.1). While the expert microscopic examination showed sensitivity of 95% (95% CI 91.4\u0026ndash;97.6), specificity of 100% (95% CI 98.7\u0026ndash;100), and accuracy of 96.7% (95% CI 96.0-98.8). The positive and negative predictive values are also provided in (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConcordance of the index and the comparator tests with the reference Nested PCR\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe weighted Cohen Kappa agreement testing values (\u0026kappa;) and 95% confidence intervals (CI) were 0.929 (0.896\u0026ndash;0.962), 0.938 (0.907\u0026ndash;0.968), and 0.959 (0.933\u0026ndash;0.984) for Mologic P\u003cem\u003ef\u003c/em\u003e Ag RDT, SD Bioline P\u003cem\u003ef\u003c/em\u003e RDT, and expert microscopy, respectively.\u003c/p\u003e\n\u003cp\u003eFigure (1) illustrates the Receiver Operating Characteristic Curve, which compares the diagnostic performance of three malaria diagnostic methods, expert microscopy, RDT (SD Bioline), and RDT (Mologic) with the reference line representing a random classifier.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eRapid diagnostic tests have revitalized the global malaria elimination agenda by offering simple-to-use, quick, and yet accurate test options that are amenable to resource-constrained settings. This descriptive study was designed to assess the performance of a novel improved \u003cem\u003eP. falciparum\u003c/em\u003e LDH (Mologic P\u003cem\u003ef\u003c/em\u003e Ag card) for diagnosing \u003cem\u003efalciparum\u003c/em\u003e malaria in areas of HRP2 deletion threads. The sensitivity, specificity, and accuracy of Mologic RDT have revealed that its performance, though seemingly less than other comparators, was not significantly different from them. It has been reported earlier that LDH-dependent RDTs have lower sensitivity [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. This novel product has shown that improved LDH-dependent RDT sensitivity can be achieved to bridge the gap created by HRP2 deletion. HRP2 gene deletion, a newly emerging threat to an important diagnostic tool, is reported in Ethiopia, Peru, and Sudan and seems to be progressive, so the introduction of improved LDH RDTs is required and timely [\u003cspan additionalcitationids=\"CR20\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe novel Mologic RDT showed slightly less sensitivity than HRP2-based SD Bioline RDT and expert microscopy. However, it demonstrated complete concordance with expert microscopy in avoiding false-positive results compared to the reference PCR, resulting in a specificity of 100%. The HRP2 antigen-dependent RDTs in this study showed high sensitivity comparable with expert microscopy, despite seven samples not being detected by this RDT. This implies the need for a supplementary RDT, such as Mologic, to diagnose those cases suspected of HRP2 gene deletion. This gene deletion is evident because these samples were detected by PCR, Mologic, and expert microscopy. The emergence of HRP2 deletion is becoming a reality in malaria-endemic areas, necessitating the introduction of novel diagnostic tools to help manage patients harboring this gene [\u003cspan additionalcitationids=\"CR23\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThis study showed that LDH Mologic's low sensitivity is mostly in the lower parasite count profile, probably making it unfavorable for elimination screening and only suited for symptomatic clinical management. Eliminating malaria is a global target within the Sustainable Development Goals, and countries should be able to detect both symptomatic and low parasitemia in their endeavors to eliminate malaria [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Concordance and the area under the curve have demonstrated that Mologic is a well-suited diagnostic rapid tool for managing \u003cem\u003eP. falciparum\u003c/em\u003e malaria.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, Mologic LDH-based RDTs have demonstrated performance comparable to that of the standard expert microscopic examination and the in-use HRP2 antigen-dependent RDT. Mologic can help detect parasites harboring an emerging HRP2 gene deletion.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eWHO: World Health Organization\u003c/p\u003e\n\u003cp\u003eRDT: Rapid Diagnostic Test\u003c/p\u003e\n\u003cp\u003eMOH: Ministry of Health\u003c/p\u003e\n\u003cp\u003eHRP2: Histidine-rich Protein-2\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIEND: Institute of Endemic Diseases, University of Khartoum, Sudan\u003c/p\u003e\n\u003cp\u003ePCR: polymerase chain reaction\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;pLDH: \u003cem\u003ePlasmodial\u003c/em\u003e lactate dehydrogenase\u003c/p\u003e\n\u003cp\u003eCI:\u0026nbsp;confidence interval\u003c/p\u003e\n\u003cp\u003eROC: Receiver Operating Characteristic\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAUC: Area Under Curve\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDBS: dried blood spots\u003c/p\u003e\n\u003cp\u003eFIND: global alliance for diagnostics\u003c/p\u003e\n\u003cp\u003eGS: Gezira Slanj\u003c/p\u003e\n\u003cp\u003eSOR: Alsororab\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study protocol was reviewed and received ethical approval from the National Ethics Committee, Federal Ministry of Health, Sudan (REF NO: FMoH/ERC, Date: 15/09/2020), and the Medical and Health Sciences Ethical Committee, University of Khartoum (REF: FM/DO/EC, Date: 22/01/2020).\u003c/p\u003e\n\u003cp\u003eInformed written consent was obtained from all participants aged 18 years or older. For children aged 5 years and older but younger than 13 years, consent was sought from their parents or legal guardians. For children aged 13 years and older but younger than 18 years, assent from the child and consent of the parent or legal guardian were obtained.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and analysed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003cstrong\u003e\u003cu\u003e\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Australian Government funded this study, Department for Foreign Affairs and Trade, as part of the FIND Malaria Innovation Platform Project.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMMA, SD, AOM: proposal development, study design, and implementation of research. AOM: supervision of medical officers and sample collection. AOM, MMA, WMA, MC: Data analysis and interpretation, draft preparation, critical appraisal, and revision of the final manuscript. FOM, AE, and MMA: Sample collection, data entry, and PCR test performance. WMA, SBA, SAM, and MC: Data curation and analysis. SAM and TE: Expert microscopy examination. MMA, AOM, WMA, AE, and MC: reviewed the manuscript. All authors read and approved of the final manuscript.\u003cstrong\u003e\u003cu\u003e\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank the directors and all staff at the two hospitals in GS and SOR for their assistance and collaboration in patient recruitment and performing on-site microscopy. Also, we would like to thank the WHO Malaria NAAT EQA (External Quality Assessment) scheme for providing malaria positive DNA samples for the PCR assays.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; details\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAbdelrahim O. Mohamed\u003csup\u003e1,2\u003c/sup\u003e, Muzamil M. Abdel Hamid\u003csup\u003e1*\u003c/sup\u003e, Waleed M. A. Jebreel\u003csup\u003e1\u003c/sup\u003e, Martin Chamai\u003csup\u003e3\u003c/sup\u003e, Shaden B. A. Ahmed\u003csup\u003e1,\u003c/sup\u003e Fayad Osman Mohammed\u003csup\u003e1\u003c/sup\u003e, Arwa Elaagip\u003csup\u003e1\u003c/sup\u003e, Musab M. Albsheer\u003csup\u003e1,4\u003c/sup\u003e, Sabine Dittrich\u003csup\u003e5\u003c/sup\u003e, Sayed A. Mustafa\u003csup\u003e6\u003c/sup\u003e, Tarig Elfaki\u003csup\u003e6\u003c/sup\u003e, Xavier Ding\u003csup\u003e5,7\u003c/sup\u003e.\u003csup\u003e\u0026nbsp;\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u0026nbsp;\u003c/sup\u003eDepartment of Parasitology and Medical Entomology, Institute of Endemic Diseases, University of Khartoum, Khartoum, Sudan. \u003csup\u003e2\u003c/sup\u003e Department of Biochemistry, Faculty of Medicine, University of Khartoum, Khartoum, Sudan. \u003csup\u003e3\u0026nbsp;\u003c/sup\u003eWest Africa Centre for Cell and Molecular Biology of Infectious Pathogens, University of Ghana, LG, Accra, Ghana. \u003csup\u003e4\u0026nbsp;\u003c/sup\u003eFaculty of Medical Laboratory Sciences, Sinnar University, Sinnar, Sudan. \u003csup\u003e5\u0026nbsp;\u003c/sup\u003eFIND, Geneva, Switzerland. \u003csup\u003e6\u0026nbsp;\u003c/sup\u003eMalaria Control Program, Federal Ministry of Health, Khartoum, Sudan.\u003csup\u003e7\u0026nbsp;\u003c/sup\u003e.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eWorld Health Organization\u003cstrong\u003e.\u003c/strong\u003e World malaria report 2024. 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Current infectious disease reports. 2018;20:1-8.\u003c/li\u003e\n\u003cli\u003eMekonen B, Dugassa S, Feleke S, Dufera B, Gidisa B, Adamu A, \u003cem\u003eet al\u003c/em\u003e. Widespread pfhrp2/3 deletions and HRP2-based false-negative results in southern Ethiopia. Malar J. 2024;23(1):108.\u003c/li\u003e\n\u003cli\u003eFontecha G, Mej\u0026iacute;a R, Banegas E, Ade M, Mendoza L, Ortiz B, \u003cem\u003eet al\u003c/em\u003e. Deletions of pfhrp2 and pfhrp3 genes of \u003cem\u003ePlasmodium falciparum\u003c/em\u003e from Honduras, Guatemala and Nicaragua. Malar J. 2018;17(1):320.\u003c/li\u003e\n\u003cli\u003eBoush M, Djibrine M, Mussa A, Talib M, Maki A, Mohammed A, \u003cem\u003eet al\u003c/em\u003e. \u003cem\u003ePlasmodium falciparum\u003c/em\u003e isolate with histidine-rich protein 2 gene deletion from Nyala City, Western Sudan. Scientific Reports. 2020;10(1):12822.\u003c/li\u003e\n\u003cli\u003eHamid M, Mohamed A, Mohammed F, Elaagip A, Mustafa S, Elfaki T, \u003cem\u003eet al\u003c/em\u003e. Diagnostic accuracy of an automated microscope solution (miLab\u0026trade;) in detecting malaria parasites in symptomatic patients at point-of-care in Sudan: a case\u0026ndash;control study. Malar J. 2024;23(1):200.\u003c/li\u003e\n\u003cli\u003eYu H, Mohammed F, Abdel Hamid M, Yang F, Kassim Y, Mohamed A, \u003cem\u003eet al\u003c/em\u003e. Patient-level performance evaluation of a smartphone-based malaria diagnostic application. Malar J. 2023;22(1):33.\u003c/li\u003e\n\u003cli\u003eOyegoke O, Maharaj L, Akoniyon O, Kwoji I, Roux A, Adewumi T, \u003cem\u003eet al\u003c/em\u003e. Malaria diagnostic methods with the elimination goal in view. Parasitology research. 2022;121(7):1867-1885.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table 2","content":"\u003cp\u003eTable 2 is available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"malaria-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"malj","sideBox":"Learn more about [Malaria Journal](http://malariajournal.biomedcentral.com/)","snPcode":"12936","submissionUrl":"https://submission.nature.com/new-submission/12936/3","title":"Malaria Journal","twitterHandle":"@malariajournal","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Clinical evaluation, lateral flow, Rapid Diagnostic Test, diagnostic accuracy, malaria, field testing, Plasmodium falciparum, Sudan","lastPublishedDoi":"10.21203/rs.3.rs-7124055/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7124055/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003eMalaria diagnosis by Rapid Diagnostic Test (RDTs) is challenged by the newly emerging histidine-rich protein 2 (HRP2) gene deletion in the \u003cem\u003ePlasmodium falciparum\u003c/em\u003e species. The alternative lactate dehydrogenase (LDH)-dependent RDTs suffer from low sensitivity, and improvement in the sensitivity of LDH RDTs is the cornerstone for detecting (HRP2) gene deletion species. This study aimed to evaluate a novel improved Mologic LDH-dependent RDT for the diagnosis of \u003cem\u003eP. falciparum\u003c/em\u003e malaria in partnership with FIND, Switzerland.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eThis is a descriptive cross-sectional study evaluating the clinical performance of improved Mologic \u003cem\u003eP. falciparum\u003c/em\u003e LDH RDTs in two rural sites in Khartoum state, Sudan. Five hundred patients presenting with symptoms suggestive of malaria in the two primary care health centers were included after signing an informed consent. On-site microscopy screening, resulting in positive \u003cem\u003eP. falciparum\u003c/em\u003e parasites or negative results, was included. Exclusion criteria included children under 5 years old, microscopy-positive \u003cem\u003eP. vivax\u003c/em\u003e malaria, and severely ill patients. Finger-prick blood was collected for examination with microscopy, the index Mologic RDT, the comparator RDT, and preparation of DBS blood for nested PCR. Nested PCR was used as a reference method. The tests of microscopy and RDTs were performed by different lab personnel, blinded to each other's results.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eThe mean age of the study subjects was 31 years, ranging from 5 to 80 years. Out of 500 patients, 210 were positive by PCR, 200 by expert microscopy, 193 by index Mologic RDT, and 199 by comparator RDT. The sensitivities of microscopy, index RDT, and comparator RDT were 95.24% (95% CI, 91.4\u0026ndash;97.6), 91.9% (95% CI, 87.3\u0026ndash;95.2), and 93.81% (95% CI, 89.6\u0026ndash;96.6), respectively. All tests were nearly 100% specific for the detection of \u003cem\u003eP. falciparum\u003c/em\u003e parasites. The concordance test (κ) showed more than 0.929 for all the tests. Seven samples were \u003cem\u003eP. falciparum\u003c/em\u003e HRP2 Ag negative and were detected by Mologic RDT.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eThe novel Mologic P\u003cem\u003ef\u003c/em\u003e LDH RDT showed performance concordant with standard expert microscopy and the comparator P\u003cem\u003ef\u003c/em\u003e HRP2 Ag RDT. The lower sensitivity of the Mologic P\u003cem\u003ef\u003c/em\u003e RDT, although not significant, makes it suitable for the clinical management of \u003cem\u003eP. falciparum\u003c/em\u003e HRP2-negative malaria.\u003c/p\u003e","manuscriptTitle":"Clinical evaluation of lateral flow Mologic malaria P.f Ag (LDH) Rapid Diagnostic Test diagnostic accuracy: A cross-sectional study, Sudan 2020-2021","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-29 21:28:41","doi":"10.21203/rs.3.rs-7124055/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-21T09:28:38+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-14T20:13:56+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-14T10:07:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"7973476327156804151428368305008071593","date":"2025-08-10T13:22:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"154708514278996968000547969095412514240","date":"2025-08-09T08:12:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"57987047978120145958436986788132828429","date":"2025-07-28T05:38:51+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-28T04:13:04+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-16T08:54:59+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-16T08:54:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"Malaria Journal","date":"2025-07-14T19:17:37+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"malaria-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"malj","sideBox":"Learn more about [Malaria Journal](http://malariajournal.biomedcentral.com/)","snPcode":"12936","submissionUrl":"https://submission.nature.com/new-submission/12936/3","title":"Malaria Journal","twitterHandle":"@malariajournal","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7772d93b-ae2a-4d54-9c1a-a7a29289f391","owner":[],"postedDate":"July 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-03T16:02:26+00:00","versionOfRecord":{"articleIdentity":"rs-7124055","link":"https://doi.org/10.1186/s12936-025-05609-x","journal":{"identity":"malaria-journal","isVorOnly":false,"title":"Malaria Journal"},"publishedOn":"2025-10-29 15:58:11","publishedOnDateReadable":"October 29th, 2025"},"versionCreatedAt":"2025-07-29 21:28:41","video":"","vorDoi":"10.1186/s12936-025-05609-x","vorDoiUrl":"https://doi.org/10.1186/s12936-025-05609-x","workflowStages":[]},"version":"v1","identity":"rs-7124055","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7124055","identity":"rs-7124055","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}