Abstract:

Objective To examine the Dengue virus (DENV) NS1 antigen and (or)the IgG/IgM antibody by gold immunochromatographic assay (GICA), and evaluate its preliminary clinical application effect. Methods 2 633 serum samples of which DENV nucleic acid has been tested by polymerase chain reaction (PCR)-fluorescence probe technique were separated into 3 groups: 948 samples of NS1 antigen in group Ⅰ, 1 156 samples of IgG/IgM antibody in group Ⅱ, and 529 samples of both NS1 antigen and IgG/IgM antibody in group Ⅲ have been tested by GICA. In addition, NS1 antigen and IgG/IgM antibody of 5 epidemic hemorrhagic fever antibody positive samples, 4 rubella/measles antibody positive samples as well as 50 samples of healthy subjects as group Ⅳ have also been tested by the same technique. Results The positive, negative and total coincidence rate of group Ⅰ compared to that of PCR were 89.09%, 92.41% and 89.87% respectively (P<0.01); The positive, negative and total coincidence rate of group Ⅱ were 64.68%, 66.41% and 64.88% respectively (P<0.01); The positive, negative and total coincidence rate of group Ⅲ were 64.68%, 66.41% and 64.88% (P>0.05). Among group Ⅲ, 419 samples showed positive by PCR. The positive rate of NS1 antigen, IgG/IgM antibody and both (or either)were 85.20%, 63.25% and 93.57% respectively. All results of group Ⅳ showed negative, and the specificity was 100%. Conclusions The union test results of the DENV NS1 antigen and the IgG/IgM antibody are comparable with those of PCR and the specificity is good. Therefore, it may be used for early auxiliary diagnosis and screening of the DENV.

Key words: Gold immunochromatographic assay, NS1antigen, IgG/IgM antibody, Polymerase chain reaction-fluorescent probe method, Dengue virus