Over a two-year period, despite widespread availability of diagnostic testing for both dengue and COVID-19, only 21 cases of COVID-19 infection with false-positive dengue IgM and 2 cases of dengue and SARS-CoV-2 co-infection were identified at our centre, forming <0.5% of all COVID-19 cases admitted over the same time period. This evidence concerns the gene CD40LG and COVID-19.