Background: Dengue is an emerging infectious disease that infects up to 390 million people yearly. The growing demand of dengue diagnostics especially in low-resource settings gave rise to many rapid diagnostic tests (RDT). This study evaluated the accuracy and utility of ViroTrack Dengue Acute - a new biosensors-based dengue NS1 RDT, SD Bioline Dengue Duo NS1/IgM/IgG combo - a commercially available RDT, and SD Dengue NS1 Ag enzyme-linked immunosorbent assay (ELISA), for the diagnosis of acute dengue infection. Methods: This prospective cross-sectional study consecutively recruited 494 patients with suspected dengue from a health clinic in Malaysia. Both RDTs were performed onsite. The evaluated ELISA and reference tests were performed in a virology laboratory. The reference tests comprised of a reverse transcription-polymerase chain reaction and three ELISAs for the detection of dengue NS1 antigen, IgM and IgG antibodies, respectively. The diagnostic performance of evaluated tests was computed using STATA version 12. Results: The sensitivity and specificity of ViroTrack were 62.3% (95%CI 55.6–68.7) and 95.0% (95%CI 91.7–97.3), versus 66.5% (95%CI 60.0–72.6) and 95.4% (95%CI 92.1–97.6) for SD NS1 ELISA, and 52.4% (95%CI 45.7–59.1) and 97.7% (95%CI 95.1–99.2) for NS1 component of SD Bioline, respectively. The combination of the latter with its IgM and IgG components were able to increase test sensitivity to 82.4% (95%CI 76.8–87.1) with corresponding decrease in specificity to 87.4% (95%CI 82.8–91.2). Although a positive test on any of the NS1 assays would increase the probability of dengue to above 90% in a patient, a negative result would only reduce this probability to 23.0–29.3%. In contrast, this probability of false negative diagnosis would be further reduced to 14.7% (95%CI 11.4–18.6) if SD Bioline NS1/IgM/IgG combo was negative. Conclusions: The performance of ViroTrack Dengue Acute was comparable to SD Dengue NS1 Ag ELISA. Addition of serology components to SD Bioline Dengue Duo significantly improved its sensitivity and reduced its false negative rate such that it missed the fewest dengue patients, making it a better point-of-care diagnostic tool. New RDT like ViroTrack Dengue Acute may be a potential alternative to existing RDT if its combination with serology components is proven better in future studies.

Diverse clinical manifestation makes early dengue diagnosis difficult. Detection of dengue non structural antigen-1 (NS1) can confirm dengue diagnosis early. This study aimed to compare the diagnostic accuracy of a new biosensors-based rapid diagnostic test (RDT) and an enzyme-linked immunosorbent assay (ELISA) for the detection of dengue NS1 antigen. 91 archived serum samples previously collected from hospitalised patients with suspected dengue were used. 50 cases and 41 controls were ascertained using reverse transcription-polymerase chain reaction, Pan-E Dengue Early ELISA, Immunoglobulin M ELISA, and haemagglutination inhibition. The samples were tested on ViroTrack Dengue Acute and SD Dengue NS1 Ag ELISA by two independent researchers blinded to the reference standard. Statistical analysis was performed using STATA version 12. The sensitivity and specificity of ViroTrack were 92.0% (95%CI 80.8-97.8) and 95.1% (95%CI 83.5-99.4), as compared to 82.0% (95%CI 68.6-91.4) (p=0.03) and 92.7% (95%CI 80.1-98.5) (p=0.32) for the ELISA, respectively. The positive and negative predictive values were 95.8% (95%CI 85.7-99.5) and 90.7% (95%CI 77.9-97.4) for ViroTrack, versus 93.2% (95%CI 81.3-98.6) (p-0.58) and 80.9% (95%CI 66.7-90.9) (p=0.18) for the ELISA, respectively. The diagnostic accuracy of ViroTrack was comparable to ELISA. It may be a more efficient tool for the diagnosis of acute dengue in low resource settings

Dengue is a major threat to public health globally. While point-of-care diagnosis of acute/recent dengue is available to reduce its mortality, a lack of rapid and accurate testing for the detection of previous dengue remains a hurdle in expanding dengue seroepidemiological surveys to inform its prevention, especially vaccination, to reduce dengue morbidity. This study evaluated ViroTrack Dengue Serostate, a biosensors-based semi-quantitative anti-dengue IgG (immunoglobulin G) immuno-magnetic agglutination assay for the diagnosis of previous and recent dengue in a single test. Blood samples were obtained from 484 healthy participants recruited randomly from two communities in Petaling district, Selangor, Malaysia. The reference tests were Panbio Dengue IgG indirect and capture enzyme-linked immunosorbent assays, in-house hemagglutination inhibition assay, and focus reduction neutralization test. Dengue Serostate had a sensitivity and specificity of 91.1% (95%CI 87.8–93.8) and 91.1% (95%CI 83.8–95.8) for the diagnosis of previous dengue, and 90.2% (95%CI 76.9–97.3) and 93.2% (95%CI 90.5–95.4) for the diagnosis of recent dengue, respectively. Its positive predictive value of 97.5% (95%CI 95.3–98.8) would prevent most dengue-naïve individuals from being vaccinated. ViroTrack Dengue Serostate’s good point-of-care diagnostic accuracy can ease the conduct of dengue serosurveys to inform dengue vaccination strategy and facilitate pre-vaccination screening to ensure safety.