Lungs affected by Covid-19 coronavirus. Coloured 3D computed tomography (CT) scan of human lungs (viewed from above) affected by Covid-19 atypical pneumonia (patchy red/yellow areas), with models of the coronavirus that causes the disease. Covid-19 is a respiratory infection that can lead to fatal pneumonia. It is caused by the coronavirus SARS-CoV-2 (previously known as 2019-nCoV) which was first identified in Wuhan, China, in December 2019. The coronaviruses take their name from their crown (corona) of surface proteins, which are used to attach and penetrate their host cells. As of March 2020, the virus has spread to many countries worldwide. Around 90,000 have been infected with several thousand deaths.