珠三角地区吸毒人群丙型肝炎病毒亚型分布状况

Distribution of hepatitis C virus subtypes among drug users in Pearl River Delta

目的了解珠三角地区吸毒人群丙型肝炎病毒(HCV)亚型的种类和组成。方法根据珠三角地区9个地级市艾滋病吸毒哨点的HCV患病率计算最低样本量,对吸毒哨点2014-2015年HCV抗体阳性样本进行系统抽样,得样本455份。通过提取样本RNA、PCR扩增、基因片段测序、构建不同片段进化树来确定亚型,并对其流行病学资料进行统计分析。结果 455份样本中,亚型及比重为1a(2.4%)、1b(7.0%)、2a(0.2%)、3a(16.9%)、3b(10.8%)、6a(61.5%)、6e(0.9%)、6k(0.2%)。亚型在年龄(χ2=30.798,P<0.05)、户籍所在地(χ2=12.924,P<0.05)、民族(χ2=21.432,P<0.05)的分布差异有统计学意义。6e与广西参考株有78%可靠性。1b、3a、6a分支下有小型进化簇。结论珠三角的吸毒人群中,6a是主要亚型,6e由广西传入。各亚型感染来源一致,存在小范围跨市传播情况。

Objective To define the main gene subtypes of hepatitis C virus（HCV）infestors among drug users in the Pearl River Delta,Guangdong province.Methods The sample size of nine cities in the province was determined according to HCV prevalence monitored by HIV sentinel of drug users.Systematic sampling was adopted for the samples of each city and 455 samples were collected in total.The gene sequences were acquired after PCR,DNA amplification,gene fragment sequencing and constructed phylogenetic analysis.Statistical analysis was made on the demographic data.Results Out of the 455 samples,the subtypes and proportion were found as 1a（2.4%）,1b（7.0%）,2a（0.2%）,3a（16.9%）,3b（10.8%）,6a（61.5%）,6e（0.9%）,and 6k（0.2%）.The difference of subtypes in age（x^2=30.798,P〈0.05）,place of permanent residency（χ^2=12.924,P〈0.05）and ethnic groups（χ^2=21.432,P〈0.05）was statistically significant.6eshowed 78% reliability with standard strain from Guangxi.There was cluster under phylogenetic tree of 1b,3aand 6a.Conclusion 6ais the main subtype among drug users in the Pearl River Delta.6eis introduced from Guangxi.The source of each subtype is consistent,and there is a small range of cross city transmission.