The virus MERS-CoV is a new member of the beta group of coronavirus, Betacoronavirus, lineage C. MERS-CoV genomes are phylogenetically classified into two clades, clade A and B. The earliest cases of MERS were of clade A clusters (EMC/2012 and Jordan-N3/2012), and new cases are genetically distinct (clade B).[10]
MERS-CoV is distinct from SARS coronavirus and distinct from the common-cold coronavirus and known endemic human betacoronaviruses HCoV-OC43 and HCoV-HKU1.[11] Until 23 May 2013, MERS-CoV had frequently been referred to as a SARS-like virus,[12] or simply the novel coronavirus, and early it was referred to colloquially on messageboards as the "Saudi SARS".