(A) Taxonomy of Coronaviridae according to the International Committee on Taxonomy of Viruses. (B) Phylogenetic tree of 50 coronaviruses with partial nucleotide sequences of RNA-dependent RNA polymerase. The tree was constructed by the neighbor-joining method using MEGA 5.0. The scale bar indicates the estimated number of substitutions per 20 nucleotides. Abbreviations (accession numbers): AntelopeCoV, sable antelope coronavirus (EF424621); BCoV, bovine coronavirus (NC_003045); BdCoV HKU22, bottlenose dolphin coronavirus HKU22 (KF793826); BuCoV HKU11, bulbul coronavirus HKU11 (FJ376619); BWCoV-SW1, beluga whale coronavirus SW1 (NC_010646); CMCoV HKU21, common-moorhen coronavirus HKU21 (NC_016996); DcCoV UAE-HKU23, dromedary camel coronavirus UAE-HKU23 (KF906251); ECoV, equine coronavirus (NC_010327); ErinaceousCoV, betacoronavirus Erinaceus/VMC/DEU/2012 (NC_022643); FIPV, feline infectious peritonitis virus (AY994055); HCoV-229E, human coronavirus 229E (NC_002645); HCoV-HKU1, human coronavirus HKU1 (NC_006577); HCoV-NL63, human coronavirus NL63 (NC_005831); HCoV-OC43, human coronavirus OC43 (NC_005147); Hi-BatCoV HKU10, Hipposideros bat coronavirus HKU10 (JQ989269); IBV-partridge, avian infectious bronchitis virus partridge isolate (AY646283); IBV-peafowl, avian infectious bronchitis virus peafowl isolate (AY641576); KSA-CAMEL-363, KSA-CAMEL-363 isolate of Middle East respiratory syndrome coronavirus (KJ713298); MERS-CoV, Middle East respiratory syndrome coronavirus (NC_019843.3); MHV, murine hepatitis virus (NC_001846); Mi-BatCoV 1A, Miniopterus bat coronavirus 1A (NC_010437); Mi-BatCoV 1B, Miniopterus bat coronavirus 1B (NC_010436); Mi-BatCoV HKU7, Miniopterus bat coronavirus HKU7 (DQ249226); Mi-BatCoV HKU8, Miniopterus bat coronavirus HKU8 (NC_010438); MRCoV HKU18, magpie robin coronavirus HKU18 (NC_016993); MunCoV HKU13, munia coronavirus HKU13 (FJ376622); My-BatCoV HKU6, Myotis bat coronavirus HKU6 (DQ249224); NeoCoV, coronavirus Neoromicia/PML-PHE1/RSA/2011 (KC869678); NHCoV HKU19, night heron coronavirus HKU19 (NC_016994); PEDV, porcine epidemic diarrhea virus (NC_003436); PHEV, porcine hemagglutinating encephalomyelitis virus (NC_007732); Pi-BatCoV-HKU5, Pipistrellus bat coronavirus HKU5 (NC_009020); PorCoV HKU15, porcine coronavirus HKU15 (NC_016990); PRCV, porcine respiratory coronavirus (DQ811787); RbCoV HKU14, rabbit coronavirus HKU14 (NC_017083); RCoV parker, rat coronavirus Parker (NC_012936); Rh-BatCoV HKU2, Rhinolophus bat coronavirus HKU2 (EF203064); Ro-BatCoV-HKU9, Rousettus bat coronavirusHKU9 (NC_009021); Ro-BatCoV HKU10, Rousettus bat coronavirus HKU10 (JQ989270); SARS-CoV, SARS coronavirus (NC_004718); SARSr-CiCoV, SARS-related palm civet coronavirus (AY304488); SARSr-Rh-BatCoV HKU3, SARS-related Rhinolophus bat coronavirus HKU3 (DQ022305); Sc-BatCoV 512, Scotophilus bat coronavirus 512 (NC_009657); SpCoV HKU17, sparrow coronavirus HKU17 (NC_016992); TCoV, turkey coronavirus (NC_010800); TGEV, transmissible gastroenteritis virus (DQ443743.1); ThCoV HKU12, thrush coronavirus HKU12 (FJ376621); Ty-BatCoV-HKU4, Tylonycteris bat coronavirus HKU4 (NC_009019); WECoV HKU16, white-eye coronavirus HKU16 (NC_016991); WiCoV HKU20, wigeon coronavirus HKU20 (NC_016995).