Table 2.

Spike (S) amino acid homology of selected isolates of PEDV CV777.

Strains of CV777 were maintained in various labs around the globe, passaged partially in vivo and in vitro as discussed in the text. The original CV777 (GenBank AccNo NC_003436.1) and its derivatives maintained through sequential passage in pigs or Vero cells (CV777 APHA and Br1/87/GenBank AccNo Z254831) are almost identical, demonstrating their common origin. Only the presumed Chinese CV777 vaccine strain (GenBank AccNo KT323979, for which the authors could not find further history), whose S-protein is in fact almost identical to the Korean strain DR13 (GenBank AccNo DQ462404) is different, raising questions about the provenance and relation to this strain.