Severe acute respiratory syndrome–related coronavirus (SARSr-CoV or SARS-CoV, Betacoronavirus pandemicum) is a species of virus consisting of many known strains. Two strains of the virus have caused outbreaks of severe respiratory diseases in humans: severe acute respiratory syndrome coronavirus 1 (SARS-CoV or SARS-CoV-1), the cause of the 2002–2004 outbreak of severe acute respiratory syndrome (SARS), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the pandemic of COVID-19. There are hundreds of other strains of SARSr-CoV, which are only known to infect non-human mammal species: bats are a major reservoir of many strains of SARSr-CoV; several strains have been identified in Himalayan palm civets, which were likely ancestors of SARS-CoV-1.
These enveloped, positive-sense single-stranded RNA viruses enter host cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor. The SARSr-CoV species is a member of the genus Betacoronavirus and the only species of the subgenus Sarbecovirus (SARS Betacoronavirus).