重庆地区婴幼儿轮状病毒腹泻VP7型别分析

VP7 typing of rotavirus from children with diarrhea in Chongqing Region

目的 研究重庆地区 1998～ 2 0 0 0年度秋冬季婴幼儿轮状病毒腹泻分子流行病学。方法 采用逆转录 聚合酶链反应 (RT PCR)扩增婴幼儿腹泻便样中的编码轮状病毒VP7蛋白的全基因片段 (10 6 2bp) ,再用巢式 聚合酶链反应 (net PCR)对扩增得到的VP7基因进行分型。同时利用核苷酸序列分析方法进行分型。结果 在 1998～ 1999年度 130例婴幼儿腹泻便样中VP7基因阳性者 5 0例 (38.46 % ) ,其中G1型占 88% (4 4/5 0 ) ,G3型占 8% (4 /5 0 ) ,混合型占 4% (2 /5 0 ) ,均为G1+G3型 ;而 1999～ 2 0 0 0年度轮状病毒流行季节采集的 112份标本中VP7基因扩增阳性者 38例(33.93% ) ,其中G3型占 78.95 % (30 /38) ,G1型占 13.16 % (5 /38) ,混合型占 7.89% (3/38) ,均为G1+G3型。核苷酸序列分型结果与PCR分型结果一致。结论 重庆地区 1998～ 1999年度轮状病毒流行季节中流行的轮状病毒以G1型为主 ,而 1999～ 2 0 0 0年度轮状病毒流行季节中G3型为主 。

Objective To study VP7 type of rotavirus from children with diarrhea in Chongqing area from 1998 to 2000. Methods Double strand RNA of rotavirus extracted from stool samples was used as the template for reverse transcription of gene VP7,which was followed by nested PCR for VP7 typing. Nucleotide sequence analysis was used for VP7 typing. Results Among the 130 fecal specimens from pediatric patients with acute gastroenteritis during the epidemic season of 1998 1999, fifty specimens ( 38.46 %) were identified as rotavirus positive by RT PCR. Of these, serotype G1 was found to be largely predominant and accounted for 88% (44/50), while serotype G3 accounted for 8% (4/50), coinfection of G1 and G3 accounted for 4% (2/50) respectively. While during the next epidemic season from 1999 to 2000, thirty eight ( 33.93 %) rotavirus positive specimens were detected from 112 stool samples by RT PCR. Serotype G3 increased significantly up to 78.95 % (30/38) and became the most prevalent serotype in that season. It was found that only 13.16 % (5/38) were serotype G1, 7.89 % (3/38) were G1 and G3 mixture. The nucleotide sequence analysis results agreed with the RT PCR typing assay. Conclusions Serotype G1 and G3 were the prevalent VP7 types in Chongqing, China from 1998 to 2000. A shift from G1 to G3 was observed in the last two successive epidemic seasons of rotavirus epidemics.