Scientists have made a breakthrough in understanding how to combat two viruses that cause severe respiratory illnesses, including COVID-19. By studying the structure of the main enzyme responsible for these viruses' replication, researchers discovered that a specific compound can effectively inhibit the virus's ability to multiply. This is significant because the virus's enzyme has different structures and functions depending on which type of coronavirus it belongs to - one from pigs and another from humans. The discovery could lead to the development of new treatments that are effective against both types of viruses, offering hope for a more comprehensive solution to combat these illnesses.