广州地区献血人群中HCV感染者HCV基因分型及感染途径研究

Study on routes of infection and viral genotypes among HCV infected blood donors in Guangzhou

目的了解广州地区献血人群中HCV感染者的感染途径及其HCV基因型/亚型。方法收集2009年10月-2013年7月在广州献血并成功随访到的抗-HCV ELISA呈反应性的献血者标本296(人)份,以转录介导的扩增(TMA)方法检测其HCV RNA;对HCV RNA阴性标本采用RIBA法确证,对HCV RNA阳性标本,膜吸附法提取HCV RNA经RT-PCR扩增E1和NS5B基因后进行sanger核苷酸序列测定。运用DNASTAR,Bio Edit,Mega5.0等软件作序列分析和基因分型。对献血者HCV感染途径的调查采用问卷调查的方法。结果 296名HCV感染者中,有197人(157例RNA阳性+40例RIBA阳性)确证为HCV感染者,按照HCV感染途径分为4组:静脉吸毒组8.63%(17/197)、输血或者血制品组17.26%(34/197)、其他途径组(除静脉吸毒和输血或血制品以外的传播途径,如手术、纹身等)13.71%(27/197)和感染途径不明组60.40%(119/197)。感染者不同年龄的比例为:18岁-<25岁32.49%(64/197),25岁-<35岁26.39%(52/197),35岁-<45岁29.95%(59/197),45岁-54岁11.17%(22/197),不同感染途径中不同年龄的分布总体比较具有明显差异(P<0.05)。HCV RNA阳性者157例,其中153人成功获得HCV基因分型:HCV-1b、2a、3a、3b和6a,分别占58.17%(89/153)、4.58%(7/153)、7.84%(12/153)、3.27%(5/153)和26.14%(40/153);静脉吸毒和输血或者血制品2组间HCV基因型分布有明显差异(P<0.01):静脉吸毒组中HCV-6a占58.82%(10/17),输血或血液制品组中HCV-1b占54.16%(13/24)。结论目前广州献血人群中HCV感染者的感染途径多数尚不明确;HCV毒株以HCV-1b和6a亚型最多见,静脉吸毒者中6a的流行率较高,有输血或血制品史的献血者中1b亚型的比例较高。

Objective To study the routes of infection and viral genotypes / subtypes in volunteer blood donors infected with HCV in Guangzhou. Methods 296 samples which were reactive in ELISA test for anti-HCV were collected from individuals who donated blood voluntarily between October 2009 and July 2013 in Guangzhou and were successfully followed up.HCV RNA was tested by transcription-mediated amplification（ TMA）. Samples with undetectable HCV RNA levels were further confirmed for the presence of anti-HCV antibody using a third-generation recombinant immunoblot assay（ RIBA）. RNA were extracted from HCV RNA（ ＋） samples by membrane absorption method and were subjected to detect for the presence of E1 and NS5 B by RT-PCR followed by Sanger sequencing. Sequence analysis and HCV genotyping were performed using DNASTAR,Bio Edit and Mega5. 0 softwares. Routes of infection were identified by questionnaire surveys. Results Different percentage of routes of infection among 197 confirmed HCV infected donors（ 157 RNA positive and 40 RIBA positive）were as followed： intra venous drug use（ IVDU） 8. 63%（ 17 /197）,transfusions of blood and / or blood products 17. 26%（ 34 /197）,other routes（ such as surgery,tattoos,etc） 13. 71%（ 27 /197）,and unknown 60. 40%（ 119 /197）. The proportion in age were as followed： 18- 25 32. 49%（ 64 /197）,25- 35 26. 39%（ 52 /197）,35- 45 29. 95%（ 59 /197）,and 45- 54 11. 17%（ 22 /197）. Overall,wide age distribution and their routes of infection were significantly different（ P〈0. 05）. 153 out of 157 HCV RNA（ ＋） samples were successfully genotyped. The frequencies of subtypes HCV-1b,2a,3a,3b,6a were 58. 17%（ 89 /153）,4. 58%（ 7 /153）,7. 84%（ 12 /153）,3. 27%（ 5 /153） and 26. 14 %（ 40 /153）,respectively. There were significant difference in HCV genotype distribution between intravenous drug users and blood donors who received transfusions of blood and / or blood products（ P 0. 01）. There was high frequency of HCV-6a among blood donors in Guangzhou： 58. 82%（ 10 /17） were intra venous drug users. There was also high frequency of 1b： 54. 16%（ 13 /24）were blood donors who received transfusions of blood and / or blood products. Conclusion There was a high proportion of HCV infection with unknown routes among blood donors in Guangzhou. HCV-1b and HCV-6a were the most predominant two subtypes among blood donors in Guangzhou. There was a high proportion of subtype 6a among intra venous drug users and 1b among blood donors who received transfusions of blood and / or blood products before.