Diagnostic accuracy of the OnSite Dengue Ag rapid test in symptomatic patients from Dhaka, Bangladesh.

BACKGROUND

Dengue fever poses an extreme public health risk in the tropical and subtropical zones around the world. Prompt and correct diagnosis is critical for dengue case management and control. Dengue NS1 antigen detection is the basic diagnostic method for dengue. Although PCR is the gold standard for detecting dengue, it is expensive, equipment-intensive, and requires skilled personnel posing major challenges for many healthcare facilities. A rapid and affordable diagnostic method for dengue is essential to address these limitations.

METHODS

This study examine the clinical performance of OnSite Dengue Ag Rapid Test (developed by CTK Biotech Inc., Poway, CA, USA) utilizing 316 symptomatic patients from three outreach centers of icddr, b diagnostic unit of Dhaka, Bangladesh. RT-PCR was used as the gold standard and Bioline™ Dengue NS1 Ag (developed by Abbott Laboratories, Illinois, U.S.) was used as comparator.

RESULTS

The Overall sensitivity and specificity of OnSite Dengue Ag Rapid Test were 96.93% (95% CI: 95.03%- 98.83%) and 99.35% (95% CI: 98.46-100.23%) respectively against RT-PCR. These values were slightly higher than those of comparator device, which demonstrated sensitivity and specificity of 93.87% (95% CI: 91.22%-96.51%) and 96.73% (95% CI: 94.77%-98.69%) respectively. Between two and five days following the onset of fever, the RDT kit can detect patients and is able to detect dengue NS1 even in samples with very low viral load (high RT-PCR Ct values ≤ 36.96), indicating its high sensitivity and accuracy.

CONCLUSIONS

OnSite Dengue Ag Rapid Test demonstrated substantial potential for clinical diagnosis of symptomatic dengue patients, providing a fast, cheap and reliable detection method. Its simplicity, ease of use and minimal equipment requirements make it highly suitable for use in diverse healthcare settings, particularly in resource-limited areas around the world.