Genetic susceptibility to Covid-19, conceptual illustration. DNA (deoxyribonucleic acid) molecule surrounded by SARS-Cov-2 coronavirus particles. Covid-19 is a respiratory disease caused by the new coronavirus SARS-Cov-2, which emerged in Wuhan, China, in December 2019. Certain genes have been shown to increase the risk of developing a severe illness that requires hospitalisation and increasing the risk of death. Other genetic factors may play a role in how likely an individual is to become infected in the first place.