[Identification and characterization of enterovirus 71 isolated in Yunnan province].

OBJECTIVE: Identification and characterization of eight enterovirus 71 samples isolated from Yunnan province. METHODS: Collecting specimens from cases of Hand, Foot and Mouth Disease (HFMD), samples were identificated by RT-PCR, isolated the virus with cells. The isolating virus passaged in vero cells, and the vpl genes sequencing. Immunization the mice with the virus, neutralization test and cross-protection test were conducted with those antisera. RESULT: All samples were identified as EV71, and eight strains had cytopathic effect (CPE) in vero cells, some antisera titers were more than 1:10,000. CONCLUSION: Eight strains of the virus grow well in vero cell, antiserum showed protection against EV71 A and C4 genotype.

[Genetic characteristics of EV71 in Yunnan Province from 2009 to 2010].

In order to learn about the genetic characteristic of human enterovirus type71 (HEV71) isolated from cases of Hand, Foot and Mouth Disease (HFMD) in Yunnan Province from 2009 to 2010. 50 isolates form HFMD cases were performed entire VP1 coding region amplification by reverse transcription-polymerase chain reaction and sequencing the nucleotide sequences; then the phylogenetic tree was constructed. The complete nucleotide sequences of region VP1 of the 50 strains were all 891nt length coding 297 amino acids. The result of molecular identification of the 50 strains is HEV71. Phylogenetic analysis indicated that 48 EV71 isolates belonged to subgenotype C4a and 2 EV71 isolates belonged to genotype A. From 2009 to 2010, the pathogen of HFMD cases were EV71 strains in Yunnan province, which were co-evolved with isolates from other provinces in mainland of China. There was no significant difference found in the whole sequence of VP1 gene of the strains isolated from different regions or under different diseases occurred, but the spread of genetype A appared in Yunnan Province in 2009.