[Analysis on molecular epidemiological features of enterovirus type 71 in Guizhou Province, 2008-2011].

To study the genotype and molecular epidemiological features of enterovirus type 71 (EV71) in Guizhou Province. The hand-foot-mouth disease(HFMD) patients since 2008 in Guizhou Province were surveyed. EV71 RNA positive samples, including mild cases, death cases and cases of serious conditions, were used for subsequent cell culture and sequencing of VP1 complete gene. Genotypes were compared between domestic and foreign epidemic strains. The results showed that the main pathogenwas EV71 subtype C4a in 2008, 2009 and 2011. The nucleotide homology was 95. 3 - 99. 7% among 109 sequenced strains isolated in Guizhou Province. Guizhou strains were more similar to the representative strains from neighbor Province or City, including Shandong, Shanghai, Nanjing, Jilin and Ningbo. There was no distinct sequence difference among the isolates from either of death, mild case or case of serious condition at the nucleotide and amino acid levels. The diversity of nucleotide sequence of isolates was less within same region and year than those trans-regional strains or strains in different year.