[Genetic characterization of enterovirus 71 stains isolated in Ningxia province in 2008]

Abstract

Objective: To study the genetic characterization of enterovirus 71 (EV71) strains isolated from specimens of patients with hand-foot-mouth disease (HFMD) in Ningxia province in 2008.

Methods: All the stool, throat swab and vesicle samples that collected from patients with HFMD were cultured. The positive isolates were identified by reverse transcriptase PCR (RT-PCR) with specific primers of EV71. Complete VP1 gene sequences (891 nucleotides) of 29 strains (part of 93 EV71 strains) were determined and compared with A, B and C genotype reference EV71 strains while EV71 China isolates by homogeneity and phylogenetic tree analyses.

Results: 215 strains of EV were isolated from 439 specimens. Results from RT-PCR indicated that 93 strains belong to EV71. Phylogenetic tree analysis revealed that the selected 29 stains were clustered with reference strains of C4 subgenotype. The nucleotide identity with C4 reference strains was 91.7%-99.4%. The amino acid homogeneity was 96.6%-100.0%.

Conclusion: The recently identified EV71 strains in Ningxia province belonged to subgenotype C4 which resembled to most of the isolates in China.