Betacoronaviruses

Betacoronaviruses (β-CoVs or Beta-CoVs) are one of four genera (Alpha-, Beta-, Gamma-, and Delta-) of coronaviruses. It is in the subfamily Orthocoronavirinae in the family Coronaviridae, of the order Nidovirales. They are enveloped, positive-sense, single-stranded RNA viruses of zoonotic origin. The coronavirus genera are each composed of varying viral lineages with the betacoronavirus genus containing four such lineages: A, B, C, D. In older literature, this genus is also known as group 2 coronaviruses

Betacoronavirus
MERS-CoV particles as seen by negative stain electron microscopy. Virions contain characteristic club-like projections emanating from the viral membrane.
Illustration of a SARS-CoV-2 virion
Virus classification
(unranked):	Virus
Realm:	Riboviria
Kingdom:	Orthornavirae
Phylum:	Pisuviricota
Class:	Pisoniviricetes
Order:	Nidovirales
Family:	Coronaviridae
Subfamily:	Orthocoronavirinae
Genus:	Betacoronavirus
Subgenera and species[1][2]
Embecovirus (subgroup A) Betacoronavirus 1 Bovine coronavirus Human coronavirus OC43 China Rattus coronavirus HKU24 Human coronavirus HKU1 Murine coronavirus Mouse hepatitis virus Sarbecovirus (subgroup B) Severe acute respiratory syndrome-related coronavirus Severe acute respiratory syndrome coronavirus Severe acute respiratory syndrome coronavirus 2 Bat SARS-like coronavirus WIV1 Merbecovirus (subgroup C) Hedgehog coronavirus 1 Middle East respiratory syndrome-related coronavirus Pipistrellus bat coronavirus HKU5 Tylonycteris bat coronavirus HKU4 Nobecovirus (subgroup D) Rousettus bat coronavirus GCCDC1 Rousettus bat coronavirus HKU9 Hibecovirus Bat Hp-betacoronavirus Zhejiang2013

The Beta-CoVs of the greatest clinical importance concerning humans are OC43 (which can cause the common cold) and HKU1 of the A lineage, SARS-CoV and SARS-CoV-2 (which causes the disease COVID-19) of the B lineage,^[3] and MERS-CoV of the C lineage. MERS-CoV is the first betacoronavirus belonging to lineage C that is known to infect humans.^[4][5]

The Alphacoronavirus and Betacoronavirus genera descend from the bat gene pool.^[6][7][8]