The complete sequence analysis of Enterovirus 71 strain from the fatal case of the hand, foot and mouth disease during an epidemic of Guangdong province in 2008 / 中华微生物学和免疫学杂志

ABSTRACT

Objective To understand the genetic characteristics of Enterovirus 71 ( EVT1 ) circu-lating strains of Guangdong province in 2008. Methods We isolated an EV71 strain from the fatal case of the hand, foot and mouth disease during an epidemic of Guangdong in 2008. Its complete genome was se-quenced and analyzed comparatively. Results The results showed that the full length of EV71 GDFS-3 ge-nome( not including poly A tail ) is 7405 bp. No insertion or deletion is detected in the coding region. There are several insertions and deletions in 5'and 3'UTR. Phylogenetic analysis of GDFS-3 and reference strains showed GDFS-3 strain shares the highest nueleotide homology with TW984 strain(96.0% ) but low homology with SIN5865, MS and BrCr( about 81.0% ). GDFS-3 strain also shares the highest amino acid homology with TW984 strain(99.0% ). It clustered with reference strains of CA subgenotype in the phylogenetie tree. The nucleotide identity with CA reference strains is 91.0% -95.0%. Conclusion The phylogenetic analysis based on the entire genome demonstrates that GDFS-3 strain has the nearest genetic relationship with TW984 strains ( isolated in 2004). GDFS-3 may belong to the same subgenogroup ( CA ) with Taiwan predominant strains. Otherwise,Some mutations in 5'UTR of EV71 may play the very important role in heightened viru-lence.