Betacoronavirus

Betacoronaviruses are one of four genera of coronaviruses of the subfamily Coronavirinae in the family Coronaviridae, of the orderNidovirales. 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.

The Beta-CoVs of the greatest clinical importance concerning humans are OC43, and HKU1 of the A lineage, SARS-CoV of the B lineage, and MERS-CoV of the C lineage. MERS-CoV is the first betacoronavirus belonging to lineage C that is known to infect humans.