 The onset of the Covid-19 pandemic in early 2020 led to a dramatic decrease in dengue cases in Sri Lanka, with an increase towards the end of 2021. In order to better understand why the number of cases differed so much from year to year, researchers looked at the contributions of virological factors, human mobility, school closure and mosquito factors. They found that school closures were strongly associated with a decrease in dengue cases, as well as a decrease in the circulation of DNB2, the most common dengue serotype. Additionally, they saw a positive correlation between the number of dengue cases and the vector indices, suggesting that the presence of 80s Egyptian mosquitoes may have contributed to the spread of the disease. This article was authored by Dinoche O'Riiran, Loxirigomes, Tabushis T.P. Jadass and others.