Usefulness of Commercial Rapid Test Kits as an Effective Diagnostic Tool of Dengue Virus Infection in a Low Resource Setting

Rapid immuno-chromatographic tests (ICTs) or diagnostic kits that are commercially available were
evaluated for their sensitivity, specificity, cost and turnaround time (TAT) results with Dengue IgM/IgG
capture enzyme linked immunosorbent assays (ELISA) as the standard test, in blood samples from a
cross-section of individuals with clinical features suggestive of dengue fever attending health care
facilities in Trinidad and Tobago. Blood samples taken from 100 consented participants were
analyzed using the two rapid ICTs (SD Bioline Dengue Duo NS1/IgM/IgG and Panbio Dengue Duo
Cassette) and compared with the Dengue IgM/IgG capture ELISAs. Standardized questionnaire was
used to obtain bio and epidemiological data of the participants. The laboratory evaluation also
assessed the TAT to complete the tests as well as the cost for each test method. The laboratory
analysis on a given number (n=93) revealed that the SD Bioline was more sensitive (39.9%) than the
Panbio (22.1%; p=0.005), and specificities for both were 100%. The SD Bioline includes an extra
biomarker test with the same TAT and differs in cost by USD$ 1.14 as opposed to the Panbio. The
ELISA has a cost of USD$ 8.07 and despite its longer TAT, it has the advantage of running more
samples (1 vs 96) at a given time. While SD Bioline may be the better choice with a higher sensitivity,
dengue ELISAs should also be favourably considered as an option for diagnostic purposes. In a
resource strapped setting like the laboratories in Trinidad and Tobago, the ELISA should be preferred
because its sensitivity and specificity were higher than the Panbio and SD Bioline kits. Besides, more
samples were tested giving an effective TAT for amounts of samples completed despite a higher cost.