The Severe Acute Respiratory Syndrome (SARS) first emerged in the Guangdong Province of southern China in November 2002. Due to initially poor reporting and containment procedures, this novel respiratory disease caused a local outbreak. The worldwide effect of SARS can be attributed to one patient who stayed at the Metropole Hotel (Hong Kong) in February 2003. Dr. Jianlun Liu infected 16 others at the hotel; these guests eventually carried the virus to other countries. By the end of the SARS epidemic in July, the disease had afflicted over 8000 individuals and killed 774 in 29 countries.

SARS is caused by the SARS-associated coronavirus (SARS-CoV), a member of the Coronaviridae family.