Evaluation of a commercial dengue combo rapid test kit for the detection of NS1 and IgM

Accurate and timely diagnosis is critical for dengue patient management due to no specific treatment is available for the disease. The use of rapid diagnostic tests (RDTs) could assist in disease screening because of their simplicity and inexpensiveness but nonetheless, the performance of these tests needs to be carefully evaluated. Here, we report the performance of RVR Dengue Combo NS1-IgG/IgM Rapid Test for detection of dengue NS1 antigen and dengue-specific IgM using 98 samples that were screened initially using Panbio Dengue IgM Capture ELISA and Panbio Dengue Early Rapid Test. The positive percent agreement (PPA) between RVR Dengue Combo NS1-IgG/IgM Rapid Test and the reference comparator tests was 77.8% and negative percent agreement (NPA) was 95.7% for NS1 (kappa=0.748, P<0.001). As for IgM, the PPA and NPA was 54.5% and 100.0% respectively (kappa=0.561, P<0.001). Combining both NS1 and IgM results using a logical OR operator gave the best compromised PPA and NPA of 75.0% and 97.2% respectively (kappa=0.743, P<0.001). In another aspect, all dengue negative samples with high titer of rheumatoid factor (RF) and Hepatitis B surface Antigen (HBsAg) were tested negative for NS1, IgG and IgM using this RDT thus indicating no cross-reactivity to these interference factors.