Complete genome sequence of a new recombinant echovirus 25 strain isolated from a neonatal patient with hand, foot, and mouth disease complicated by encephalitis in Beijing, China.

Although human echovirus 25 (E-25), a type of the enterovirus B species, is implicated in aseptic meningitis, information on its gene structure, evolution, and virulence are limited. We report here the complete genome sequence of a novel recombinant E-25 strain (E25/2010/CHN/BJ) isolated from a neonate with hand, foot, and mouth disease complicated by encephalitis in Beijing, China in 2010. The complete viral genome consists of 7429 nucleotides (nts), including a 6585-nt open reading frame. Phylogenetic dendrogram based on VP1 gene regions revealed that this strain belonged to subgroup D4, which contains the other E-25 strains isolated from China in recent years. The difference in the amino acid sites (P130S, K/T135I) of the VP1 region may affect its immunogenicity. SimPlot and Bootscan analyses suggested that E25/2010/CHN/BJ is a recombination result of E-25 and Coxsackievirus B3 (CVB-3) strains. Our results would facilitate the study of the origin, evolution, and molecular epidemiology of E-25.