Performance of two commercial dengue NS1 rapid tests for the diagnosis of adult patients with dengue infection

Objective: to determine the diagnostic performance of two commercially available dengue NS1 antigen rapid detection tests (RDTs); namely the SD BIOLINE Dengue NS1 RDT and the ImmuneMed Dengue NS1 Rapid, for the diagnosis of adult patients with dengue infection. Methods: The study was performed by using archived samples from 237 patients with the laboratory-confirmed dengue infection. Archived, well-characterized samples from an additional 208 febrile individuals from Thailand were used as the control group. Reference testing to confirm the diagnosis in dengue patients included RT-PCR andin-house NS1 ELISA, in-house IgM and IgG capture ELISAs. Results: The sensitivity of the SD BIOLINE Dengue NS1 RDT was 100%, and the specificity was 99% (95%CI 96.6 to 99.7%). False positive was found in 2 samples from patient with scrub typhus. The sensitivity and specificity of the ImmuneMed Dengue NS1 Ag Rapid were 97.4% (95% CI, 95.5 to 99.5%) and 96.6% (95%CI 93.5 to 98.4%) respectively. False positive results were found in 7 patients with murine typhus, scrub typhus, and influenza. Conclusion: Both RDTs showed comparable sensitivity and specificity in this study population. Data from this study could be used to facilitate data-driven laboratory test choices for managing patient care during dengue outbreaks.