Bioanalytical Detection of Parasitic Infections: Advances in Immunological Assays and Biosensor-Based Diagnostics

Parasitic diseases continue to be an important public health problem and impact over one billion people worldwide; therefore, there is an urgent need for new, high-performance diagnostic methods that are sensitive, rapid, and accessible. Conventional parasitological and laboratory-based diagnosis can be time-consuming, require specialized equipment and highly trained personnel, and often has limited sensitivity at low parasite loads, all of which can hinder effective treatment, disease surveillance, and transmission control. This review critically analyzes the latest developments in immunological assays and new biosensor technologies for detecting parasitic infections. This review assesses established immunodiagnostic tests such as indirect immunofluorescence (IFA) assays, enzyme-linked immunosorbent assays (ELISA), and antigen-based detection methods for their analytical performance, clinical usefulness, and limitations. This review will focus on the development of electrochemical immunosensors, nucleic acid-based biosensors, and aptamer-based sensing platforms, which can offer enhanced sensitivity, selectivity, rapid response, miniaturization, and potential for point-of-care (POC) analysis. Conventional reviews discuss parasitological and/or immunological diagnostic approaches in isolation, whereas this review combines established immunodiagnostic approaches with next-generation biosensing approaches and critically evaluates the analytical transition to portable POC platforms. Lastly, we discuss opportunities for novel uses in signal amplification using nanomaterials, multiplexed detection of multiple biomarkers, microfluidic integration, and portable analytical devices. This holistic view can inform the design of rational platforms for sensitive, economical, and easy-to-deploy diagnostics for parasitic infections.