Those diseases that are caused by organisms, such as bacteria, viruses, fungi, or parasites, and can be passed from one person to another are known as infectious diseases or communicable diseases. COVID-19 is a disease that can spread from individuals who carry the virus. Small droplets from the mouth or nose are released when a person with COVID-19 coughs or exhales, this spreads the disease from one person to another. Thus, COVID-19 is an infectious disease.