Animation of the surface of a human lung cell showing ACE2 surface enzymes (light blue) being blocked by a new anti-COVID drug (dark blue). The presence of the drug on each surface protein means that the viruses (red) have no point to attach to the cell, and they roll on harmlessly. COVID-19 is caused by the new SARS-CoV-2 coronavirus. This enters the body through the lungs, where it binds to an enzyme called angiotensin converting enzyme 2 (ACE2) on the cells' surfaces. It then enters the cell and makes copies of itself. Blocking the binding sites of these enzymes may prevent the virus binding and entering the cell, stopping the progress of the disease.