Early diagnosis of Dengue infection using a commercial Dengue Duo rapid test kit for the detection of NS1, IGM, and IGG

Abstract

A commercial Dengue Duo rapid test kit was evaluated for early dengue diagnosis by detection of dengue virus NS1 antigen and immunoglobulin M (IgM)/IgG antibodies. A total of 420 patient serum samples were subjected to real-time reverse transcription-polymerase chain reaction (RT-PCR), in-house IgM capture enzyme-linked immunosorbent assay (ELISA), hemagglutination inhibition assay, and the SD Dengue Duo rapid test. Of the 320 dengue acute and convalescent sera, dengue infection was detected by either serology or RT-PCR in 300 samples (93.75%), as compared with 289 samples (90.31%) in the combined SD Duo NS1/IgM. The NS1 detection rate is inversely proportional, whereas the IgM detection rate is directly proportional to the presence of IgG antibodies. The sensitivity and specificity in diagnosing acute dengue infection in the SD Duo NS1/IgM were 88.65% and 98.75%, respectively. The assay is sensitive and highly specific. Detection of both NS1 and IgM by SD Duo gave comparable detection rate by either serology or RT-PCR.

Figure 1.

Hemagglutination inhibition (HI) value vs. positive detection rate for laboratory diagnosis of dengue. A total of 320 samples were used in the analysis. Samples were derived from the following category of samples: virus isolation positive (N = 30), dengue RT-PCR (N = 50), NS1 positive (N = 50), sero-negative acute sera but convalescent sero-converted (N = 50), random IgM positive samples (N = 100), primary dengue (N = 20), and secondary dengue (N = 20).

Figure 2.

Comparison of SD BIOLINE Dengue Duo commercial kit and conventional laboratory methods in relation to day of onset of fever. A total of 320 samples were used in the analysis. These sample panels are virus isolation positive (N = 30), dengue reverse transcription-polymerase chain reaction (RT-PCR) (N = 50), NS1 positive (N = 50), sero-negative acute sera but convalescent sero-converted (N = 50), random IgM positive samples (N = 100), primary dengue (N = 20), and secondary dengue (N = 20).