Genetic Diversity of Echovirus 6 Strains Circulating in Korea

Echovirus 6 (ECV6) is the prevalent serotype detected in aseptic meningitis cases in Korea. To analyze the genetic variation of ECV6 isolates recently circulating in Korea, we determined the partial sequence of the VP1 capsid gene from 22 Korean ECV6 isolates and performed pairwise analysis against 42 reference strains from the GenBank database using MegAlign. The 22 Korean ECV6 isolates formed 3 distinct genetic clusters: Kor-lineage Ⅰ, Ⅱ, and Ⅲ. The Korean ECV6 strains showed significant genetic diversity with 14.8~22.8% nucleotide divergence among the 3 different lineages. These ECV6 Kor-lineages were demonstrated to belong to different genetic clusters using VP1 sequence-based phylogenetic analysis, implying that the recently circulating Korean ECV6 strains have potential antigenic variation.