In 2003, a novel vesivirus (strain 2117) genetically similar to CaCV strain 48 was accidentally isolated as a contaminant in Chinese hamster ovary (CHO) cell cultures by a pharmaceutical company in Germany (13).
The sequences shared closest nucleotide identity (90.7%-92.6%) with vesivirus strains 2117, Geel/2008, Allston/2008/USA, and Allston/2009, which were identified as contaminants in CHO cells; the sequences shared 73.6%-74.8% nt identity with CaCV strain 48.
Comparison with other members of the Circoviridae demonstrated that RaCV shares the greatest sequence homology with canary circovirus (CaCV
) and pigeon circovirus (PiCV) and was more distantly related to the beak and feather disease virus, goose circovirus, duck circovirus, and the 2 porcine circoviruses, PCV1 and PCV2.
The virus, strain 48, was antigenically and genetically unrelated to feline calcivirus, was tentatively proposed as a "true" canine calicivirus (CaCV), and was included in the Vesivirus genus (6).
The sequence (3381 nt) from the 3' end of open reading frame 1 (ORF 1) to the poly-A tail of the CaCV (strain 170/07) was made available in GenBank (accession no.