Abstract: Objective To understand the genetic characteristics of the Coxsackievirus B5 (CVB5) isolated from cases of acute flaccid paralysis (AFP) in Guangdong Province from 1995 to 2024. Methods High-throughput sequencing was used to identify non-polio enteroviruses isolated from AFP surveillance in Guangdong Province from 1995 to 2024. The VP1 gene sequences of CVB5 strains in GenBank were used to construct a phylogenetic tree and study the genetic evolution of CVB5. Results 31 CVB5 strains were identified from AFP case specimens, and their VP1 sequences were obtained.The full-length VP1 sequence was 849 bp, encoding 283 amino acids, with no insertions or deletions. The nucleotide and amino acid homology of the 31 CVB5 VP1 sequences were 88.05% (76.10%-100.00%) and 97.15% (94.30%-100.00%), respectively. Among them, there was 1 strain of genotype B, 27 strains of genotype C, and 3 strains of genotype D. Evolutionary analysis of the global CVB5 VP1 region showed that most strains isolated in Asia from 1996 to 2024 were genotype C, while strains from Europe were genotype D. Conclusions CVB5 has been circulating in many parts of the world. The CVB5 strains isolated in Guangdong Province from 1995 to 2024 included three genotypes, mainly genotype C, which is the same as the prevalent genotype in Asia. The emergence of genotype D strains indicates the need for continued monitoring and research on CVB5 in Guangdong.

Key words: Coxsackievirus B5, VP1, Evolutionary analysis