Comparative study on the utility of automated chemiluminescence immunoassay for NS1 antigen-based dengue diagnosis

With newer dengue outbreaks extending to regions that were previously unaffected, about half of the world's population is now at risk of dengue infection. This scale of dengue spread and its undistinguishing primary fever symptom demands embracing automated high-throughput diagnostic techniques for quicker confirmatory diagnosis which otherwise requires time, cost and skill intensive reverse transcription-polymerase chain reaction (RT-PCR). Magnetic bead-based automated chemiluminescence immunoassay (CLIA) is one potential platform that has proven its diagnostic potential for different diseases. However, adoption of CLIA for dengue diagnosis demands extensive validation for widespread implementation. To this end, we evaluated the diagnostic performance of CLIA in comparison with routine dengue diagnostic approaches such as rapid diagnostic test (RDT) and RT-PCR. RDT and CLIA detected the presence of dengue non-structural protein 1 (NS1) antigen while RT-PCR detected the presence of viral RNA. From the analysis of 204 samples, the dengue test positive percentage was 17.6 %, 16.7 % and 19.6 % by RDT, CLIA and RT-PCR methods, respectively. CLIA exhibited a sensitivity of 77.5 %, specificity of 98.17 % and a Cohen's kappa agreement (κ) value of 0.802 with RT-PCR. In addition, CLIA also exhibited a high κ-value of 0.931 with RDT. These findings show the reliability of NS1 antigen detection using automated CLIA for dengue diagnosis. This supports the potential to adopt high-throughput automated CLIA for dengue diagnosis when resources and expertise required to meet the need for quick test result turnaround during outbreaks may be limited.