南京地区2011-2012年度门诊婴幼儿轮状病毒腹泻的分子流行病学研究

目的 了解南京地区门诊婴幼儿轮状病毒腹泻的分子流行病学特征及轮状病毒的G/P分型状况。方法 2011年7月至2012年6月对门诊腹泻患儿标本进行轮状病毒胶体金检测，阳性标本通过巢式反转录聚合酶连反应进行G/P分型，同时测序得出亚型。 结果 在2 081例腹泻标本中共检出胶体金阳性标本165例，阳性率为7.9%。轮状病毒感染的高峰季节在10月到次年2月之间， 94%的感染患儿都在2岁以下，其中13～24月龄为高发年龄段。轮状病毒分型结果表明G1, G3, G9为主要G分型，而P[8]则是最常见的P分型。常见的G／P组合为：G1P[8](16.4%)， G3P[8](13.9%)， G9P[8](24.8%)。进一步VP7和VP4基因测序比对后发现G1和G3毒株各分属于一个亚型G1 Ic，G3 Ia，而G9毒株大部分属于G9 IV亚型，同时也有一小部分毒株属于G9 III亚型，P[8]型毒株主要为P[8] II亚型，少数为P[8] IV亚型。 结论 研究结果表明G9P[8]是最主要的流行型别，同时G1P[8]和G3P[8]也占较大比例。

Molecular epidemiological research on outpatient infants with rotavirus diarrhea in Nanjing, 2011-2012

We evaluated the distribution of rotavirus G/P genotypes and performed molecular epidemiological characteristics of rotaviruses circulating in infants with diarrhea in this study. Stool specimens from the outpatient children with acute diarrhea were collected from Nanjing Maternity and Child Health Care Hospital in Nanjing during July 2011 and June 2012. Rotavirus antigen was detected by using commercial colloidal gold device, and G and P genotyping was performed by the nested RT-PCR. Results showed that group A rotavirus was detected in 165 of 2 081 (7.9%) specimens. The peak season of rotavirus infection was in the time from October to February. Of all episodes of rotavirus diarrhea, 94% occurred during the first 2 years of life, peaking at 10-12 months of age. Genotyping of rotavirus showed that G1, G3 and G9 were predominant. The P[8]was the most common P genotypes. The G/P genotype combinations were found as G1P[8](16.4%), G3P[8](13.9%) and G9P[8](24.8%). A comparison of the nucleotide sequences of the VP7 and VP4 with reference strains showed that G1 and G3 strains had the highest sequence similarity to the G1-Ic and G3-Ia strain respectively. Most of G9 strains shared with the highest homologous to G9-IV, and there were also a small part of the strains belonged to the G9-III. Analysis of VP4 region of P[8]strain showed that they were classified into cluster P[8]-II and P[8]-IV. Our results indicate that G9 P[8]was the predominant type during 2011-2012 in Nanjing.