Archived dengue serum samples produced false-positive results in SARS-CoV-2 lateral flow-based rapid antibody tests

Abstract

Co-endemicity of SARS-CoV-2 and dengue virus (DV) infection is becoming a matter of serious concern as it has been already reported that antibodies (Ab) elicited by SARS-CoV-2 infection can produce false-positive results in dengue IgG and IgM rapid tests and vice versa. Here we communicate that five of thirteen DV antibody-positive serum samples from Kolkata, archived in 2017 (predating the COVID-19 outbreak), produced false-positive results in SARS-CoV-2 IgG/IgM lateral flow-based rapid tests. Our results emphasize the importance of implementing tests with higher specificity to conduct sero-surveillance for accurate estimation of SARS-CoV-2/DV prevalence in regions where both viruses now co-exist.

Keywords: COVID-19; SARS-CoV-2; antibody test; cross-reactive; dengue virus; false-positive; strip test.

Fig. 1.

Representative images of COVID-19 and dengue rapid IgG and IgM strip tests. (a) Sample 17-D-15; (b) sample 17-D-37; (c) sample 17-D-15 test using AbCheck kit; (d) sample 17-D-16. (a, c) A serum sample confirmed positive for dengue but false-positive for COVID-19. (b) A serum sample confirmed positive for dengue but negative for COVID-19. (d) A serum sample negative for both dengue and COVID-19 antibodies.