Genotype distribution of HCV among the populations of IDUs and non-IDUs in Hainan

Objective To define the main gene subtypes and HCV-Ab, HCV-RNA of hepatitis C virus (HCV) infectors among inject drug users (IDUs) and non-inject drug users (non-IDUs) in Hainan Province. Methods The HCV-RNA(s) of 581 samples, that were from Methadone Maintenance Treatment Clinics, drug treatment center and Hainan Provincial People’s Hospital Infection Department, were extracted, amplified in the HCV Core-E1 region by RT-PCR and nested-PCR, and determine the HCV genotype distribution. Based on whether or not absence of intravenous drug abuse, the subjects were divided into IDUs group and non-IDUs group, statistical analysis was made on the demographic data. Results Among 802 methadone maintenance treatment outpatients and drug addicts in Hainan Province, 309 were HCV-Ab positive, with the HCV-Ab positive rate of 38.53%, and 215 were HCV-RNA positive, with the positive rate of 69.58%. And 251 patients tested HCV-RNA positive in Hainan People’s Hospital, 466 patients tested positive for HCV-RNA. Of the 581 HCV-Ab positive cases, 466 of them HCV-RNA positive cases.And 448 out of the 466 sampleswere successfully sequenced and genotyped as follows,the subtypes and proportion among 320 IDUs were found as 6a (58.75%) in mainly, and followed by 3b (16.88%), 3a (15.63%), 1a (4.38%), 1b (2.81%) and non-6a (0.93%); 128 non-IDUs were 1b (30.47%), 6a (28.12%), 3b (10.16%), 3a (3.91%), 1a (7.03%) and non-6a (14.84%), the difference was statistically significant ( P <0.01). Conclusion The spontaneous clearance rate of HCV infection in IDUs population was high in Hainan Province, 6a is the main subtype among IDUs, followed by 3b. There is a range transmission of HCV subtypes other than 6a in different regions. 摘要： 目的 了解海南省静脉吸毒人群 (inject drug users, IDUs) 中HCV-Ab、HCV-RNA的情况, 以及IDUs与非静 脉吸毒人群 (non-inject drug users, non-IDUs) 中丙型肝炎病毒 (Hepatitis C virus, HCV) 亚型分布特点。 方法 从海南省 的美沙酮维持治疗门诊、戒毒所和海南省人民医院住院患者中选择HCV-Ab阳性者检测HCV-RNA, 对HCV-RNA阳性 者抽取血清进行RT-PCR及巢式PCR扩增Core-E1区并测定其核酸序列、确定其基因亚型。根据是否存在静脉吸毒行 为分为IDUs组和non-IDUs组, 然后并对两组的资料统计分析。 结果 海南省802例美沙酮维持治疗门诊、戒毒所吸毒 者中HCV-Ab阳性309例, HCV-Ab阳性率38.53%, 其中215例HCV-RNA阳性, 阳性率为69.58%。海南省人民医院就 诊HCV-RNA阳性者251例, 共466例HCV-RNA检测阳性。466例HCV-RNA阳性者中448例样本成功测序和基因分 型及具体如下：IDUs组 (320例) 中6a (58.75%) 是最主要的基因型, 其次是3b (16.88%) 、3a (15.63%) 、1a (4.38%) 、1b (2.81%) 和非6a (0.93%) ; 而non-IDUs 组 (128 例) 中最主要的基因亚型是1b (30.47%), 其次是6a (28.12%) 、3b (10.16%) 、3a (3.91%) 、1a (7.03%) 和非6a (14.84%), 两组亚型之间的差异具有统计学意义( P <0.01)。 结论 海南省IDUs 人群中HCV感染后自发清除率较高, 其感染的主要亚型为6a, 其次为3b; 但有些地区的IDUs人群中存在其他亚型的小 范围流行。