A rapid point-of-care test for dengue virus-1 based on a lateral flow assay with a near-infrared fluorescent dye

Dengue fever is caused by the dengue virus (DENV), and DENV1 is the prevalent epidemic serotype in south China. A new lateral flow assay (LFA) based on a near-infrared (NIR) fluorescent dye was developed to detect anti-DENV1 IgG antibodies. DyLight-800 was used as the marker conjugated to goat anti-human IgG antibodies, and recombinant dengue type 1 envelope protein was used as the capture protein on the test line. Twenty samples from patients infected with DENV1 and 160 negative controls were analyzed using this new NIR-LFA. The results of the NIR-LFA were compared with the results of Panbio Dengue IgG ELISA and the Dengue Duo IgM/IgG Cassette. Nineteen confirmed DENV1-positive samples were identified by NIR-LFA, giving 95% (19/20) sensitivity. No significant differences existed in the results when the 20 primary clinical samples were analyzed using NIR-LFA, Panbio ELISA, and the Dengue Duo Cassette. However, NIR-LFA had a lower limit of detection than IgG ELISA and Duo IgM/IgG Cassette did when analyzing a 2-fold dilution series of the 19 samples positively identified by NIR-LFA. When incorporated with an NIR POCT device, the new NIR-LFA was rapid, easy to use, and highly sensitive in detecting DENV1, and has potential for application to clinical diagnosis.