Coronavirus is a group of RNA viruses that cause a variety of diseases in humans and other animals. COVID-19 is a new disease first identified in Wuhan China, caused by a new coronavirus that has not previously been seen in humans. In COVID-19, "CO" stands for corona, "VI" stands for virus, and D stands for disease and the 19 indicates it was first discovered in 2019. The virus is related (but is not the same) to the SARS-associated coronavirus that caused an outbreak of severe acute respiratory syndrome (SARS) in 2002-2003.