Development and Evaluation of a Rapid Diagnostic Test for Malaria Detection

Thesis Abstract

Malaria remains a leading cause of morbidity and mortality in many tropical and subtropical regions, particularly in low-resource settings where timely diagnosis is critical for effective treatment and disease control. Conventional diagnostic methods such as microscopy and polymerase chain reaction (PCR) are considered gold standards but often require sophisticated laboratory infrastructure, trained personnel, and are time-intensive, limiting their use in peripheral clinics and field settings. This study aims to develop and evaluate a cost-effective, highly sensitive, and specific rapid diagnostic test (RDT) for malaria detection to enhance early diagnosis, especially in resource-constrained environments. The primary objectives are to design an immunochromatographic assay capable of detecting Plasmodium species-specific antigens, particularly histidine-rich protein II (HRP-II) and lactate dehydrogenase (pLDH), and to evaluate the diagnostic performance of the developed RDT in comparison with existing commercial kits and laboratory-based gold standards. A cross-sectional study design was employed, involving a sample size of 500 febrile patients presenting at primary healthcare centers in a malaria-endemic region. Participants were selected through systematic random sampling, ensuring representative sampling of different age groups and genders. Data collection involved the collection of finger-prick blood samples for the rapid test, microscopy, and PCR analysis. The RDT was developed by conjugating monoclonal antibodies specific to HRP-II and pLDH antigens onto nitrocellulose strips, optimizing antibody concentrations and buffer compositions through iterative laboratory testing. Validation of the assay's technical parameters included assessing specificity, sensitivity, limit of detection, and cross-reactivity with other infectious agents. The diagnostic performance of the RDT was analyzed statistically using SPSS version 26, with receiver operating characteristic (ROC) curves constructed to determine sensitivity and specificity. Kappa statistics measured agreement with microscopy and PCR results, and the student’s t-test assessed differences in mean detection times. It is anticipated that the developed RDT will demonstrate a sensitivity of over 95% and specificity exceeding 98%, with a limit of detection that effectively identifies low parasitemia levels. Moreover, the assay is expected to reduce diagnosis time to under 15 minutes, considerably faster than microscopy and PCR, thereby facilitating immediate clinical decision-making. The study will also explore the application of the Health Belief Model to understand healthcare workers' acceptance and potential barriers to RDT implementation. This research contributes to the body of knowledge by providing an empirically validated, affordable, and easy-to-use diagnostic tool tailored for field deployment in malaria-endemic areas, addressing current limitations associated with existing RDTs. Findings will inform policymakers and health program managers regarding the practicality and accuracy of the new assay, facilitating its integration into existing malaria control strategies. In conclusion, the study underscores the potential of the newly developed RDT to improve early malaria detection, thereby reducing disease transmission, morbidity, and mortality. Recommendations include large-scale field validation across diverse epidemiological settings, training health workers in RDT usage, and establishing supply chain logistics to ensure widespread accessibility. Future research should explore the integration of digital health technologies for result reporting and surveillance purposes, further enhancing malaria control efforts in resource-limited environments.