Fireflies, also known as lightning bugs, are insects in the Lampyridae family who use bioluminescence to attract potential mates and prey. Their conspicuous glow at twilight comes from an enzyme called luciferase, which can be isolated in the lab. Now, UTMB virologists are using the enzyme to develop faster and more accurate diagnostic tests for COVID-19 as well as to analyze potential therapies and gain a clearer understanding of the SARS-CoV-2 virus itself.