A study on genetic characteristics of Enterovirus type 71 of hand-foot-mouth disease in Shaoxing city / 预防医学

ABSTRACT

Objective To undersyand the genetic characteristics of Enterovirus Type 71 (EV 71 )isolated from clinical specimens of children with hand-foot-mouth disease (HFMD)in Shaoxing city from 2012 to 2013.Methods RNA was extracted from specimens collected from stool,throat swab and vesicle from children with HFMD,and EV 71 were identified by reverse transcriptase polymerase chain reaction (RT-PCR).Ten positive samples were isolated and were amplified by segmented PCR,then,they were spliced into a full-length after sequenced according to the reference strains. Homology analysis on region VP1 and phylogenetic tree were carried out based on nucleotide sequence and amino acid sequence.Results The results indicated that the ten isolated strains were all EV 71 positive.Sequence alignment of VP1 showed that the nucleotide and amino acid homogeneity of these 10 strains were related to C4a genotypes,with 95.06%-97.87% and 93.60%-98.99% respectively.Phylogenetic tree based on VP1 indicated that these 10 strains all belonged to C4a genotype.Conclusion The identified EV 71 strains isolated from HFMD children in Shaoxing city belong to genotype C4a.