Phylogenetic analysis of enterovirus 71 isolated from patients with hand, foot and mouth disease in Guangdong and Fujian provinces, 2000-2001 / 中华实验和临床病毒学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To identify enterovirus 71 (EV71) strains isolated from patients with hand, foot and mouth disease (HFMD) in Guangdong and Fujian provinces from 2000 to 2001 by using phylogenetic analysis.</p><p><b>METHODS</b>All 25 samples were first tested for enteric viruses by RT-PCR using enterovirus specific primers EV-1 and EV-2, and then were identified for EV71 by RT-PCR using EV71 specific primers 159S and 162A. The amplicons of 485bp segment (part of the VP1 gene) were cloned into pGEM-T and sequenced. A phylogenetic tree was constructed by comparison of the sequences with other 12 EV71 strains isolated from China, Japan, Hungary, and the United States including the prototype BrCr.</p><p><b>RESULTS</b>The positive rate of EV71 was about 20%. The sequence analysis showed that the new isolate (GZH2000) shared 94%-96% nucleotide identity with three strains isolated in 1998 and 2000, and 91% with a strain isolated in 1987 from Chinese mainland, but shared only 82%-84% homology with EV71 isolates studied abroad.</p><p><b>CONCLUSIONS</b>EV71 is one of the important pathogens of HFMD in south China. The strains isolated from mainland were closely related with most isolates from Taiwan, but different from most EV71 strains reported abroad. The symptoms of EV71 infection in mainland were not as intensive as those described in Taiwan's outbreak.</p>