ENTEROVIRUS-71 ISOLATED FROM CHINA IS SEROLOGICALLY SIMILAR TO THE PROTOTYPE E71 BRCR STRAIN BUT DIFFERS IN THE 5'-NONCODING REGION

Enterovirus 71 H (E71 H), an isolate from an adult patient with hand-f oot-mouth disease (HFMD) in China, was serologically similar to the pr ototype strain E71 BrCr, which was isolated from a patient with asepti c meningitis. The study further analyzed the similarity of E71 H to E7 1 BrCr at the 5'-noncoding region (NCR), a location in genomic RNA tha t recently was found to be related to neurovirulence in poliovirus and Venezuelan equine encephalitis virus. Using a reverse transcription-p olymerase chain reaction (RT-PCR) technique and a unique primer pair I , a 397 bp product was detected from E71 BrCr, Cox A9 (Griggs), Cox A 16 (NIH), Cox 61 (HA antigen 201-468), Cox B5 (wild type), and ECHO 11 (Gregory), but not from E71 H, Cox A24 (Joseph), and ECHO 5 (Noyce). However, all of the viruses generated a 154 bp product using a univers al enterovirus primer pair II. Further comparative analysis using prim er-directed sequencing of both the E71 H and E71 BrCr 154 bp products revealed that they differed by 12 bases. The variations between the tw o viruses were clustered in two loci, one in the region of nucleotides 43-61 with eight variations, and the other in the region of nucleotid es 120-133 with three variations. The differences within the 5'-NCR be tween the E71 H (HFMD) and the E71 BrCr (aseptic meningitis) viruses m ight provide a clue to explain why E71 was associated with two differe nt clinical patterns: polio-like disease in the United States, Austral ia, and Eastern Europe, HFMD in China, Japan, and Singapore. (C) 1995 Wiley-Liss, Inc.