Two-Color Duplex Platform for Point-of-Care Differential Detection of Malaria and Typhoid Fever

Malaria and typhoid fever are two febrile illnesses prevalent in the tropics that often present overlapping symptoms. In this work, we demonstrate an optical reader-based diagnostics platform for rapid codetection and quantification of two antigen targets: lipopolysaccharide (LPS) for typhoid fever and plasmodium lactate dehydrogenase (pLDH) for malaria infections. We report a limit of detection (LoD) of 5 ng/mL for LPS and 10 ng/mL for pLDH in a spiked serum test. We also validated the duplex test's performance of differentiating malaria infection, typhoid fever infection, and coinfection by testing clinical samples in human serum. Our platform provides the potential for further multiplexing by encoding different color codes to various detection targets. The rapid result (similar to 15 min), low cost (similar to$2), and minimal volume requirement for human serum clinical samples (4 L) of our diagnostic platform offer great potential for deployment in resource-limited settings to help distinguish common causes for acute febrile illnesses at the point-of-need.

Automated summary

This study demonstrates an optical reader-based diagnostics platform for rapid detection of malaria and typhoid fever, with the potential to differentiate between different infections. The platform offers rapid results, low cost, and minimal sample volume requirements, making it suitable for deployment in resource-limited settings to distinguish common causes of acute febrile illnesses at the point-of-need.