Sarbecovirus

Sarbecovirus is a subgenus of Betacoronavirus within the family Coronaviridae and the subfamily Orthocoronavirinae. It comprises SARS-related coronaviruses, most notably SARS-CoV and SARS-CoV-2, the agents of the 2002–2004 SARS outbreak and the COVID-19 pandemic, respectively. The subgenus, defined by the ICTV, includes several bat-associated viruses identified in recent decades.

Viruses in this group are enveloped, positive-sense single-stranded RNA viruses with genomes typically around 27 to 32 kilobases in length. They encode the spike glycoprotein that mediates entry into host cells. Receptor usage is primarily human ACE2 for SARS-CoV and SARS-CoV-2, though receptor usage can vary among sarbecoviruses; other members may use related receptors or alternative entry strategies.

Natural hosts are bats, particularly horseshoe bats of the genus Rhinolophus. Spillover events have produced human infections, sometimes via intermediate hosts, as seen in SARS and potentially in the origins of SARS-CoV-2, though the exact pathway remains under study. Zoonotic risk is driven by close contact between wildlife and humans and by viral genetic diversity and recombination in reservoir populations.

Notable members include SARS-CoV and SARS-CoV-2. Bat-derived sarbecoviruses such as RaTG13 have been used as reference genomes due to their close relationship with SARS-CoV-2. Taxonomic classification is subject to updates as new viruses are discovered and analyzed.