深圳献血者中HCV感染自然清除与病毒血症特征分析

Classification and characterization to spontaneous recovery and chronic HCV infection from blood donors in Shenzhen

目的测定我国深圳地区献血者中的丙型肝炎病毒(hepatitis C virus,HCV)感染者自然清除和病毒血症,即自然康复与慢性感染者比率及其人群特征,为丙型肝炎防治研究提供数据。方法对深圳献血者中抗-HCV初筛阳性的血清标本采用2种EIA方法进行抗体再测定,以定量PCR方法测定病毒载量,并采用巢式PCR对核酸进行确认,进而将标本分为3种HCV感染状态,即病毒自然清除(RNA-/Ab+)、病毒血症(RNA+/Ab+)和假阳性(RNA-/Ab-),通过统计学方法分析3种感染状态献血者在临床信息(性别、年龄)、ALT、抗-HCV的差异。HCV RNA阳性标本通过分析5'-NCR序列进行基因分型。结果 152份初筛抗-HCV阳性的标本中,病毒自然清除标本45份、病毒血症51份、假阳性56份。50份HCV定量PCR阳性标本病毒载量范围从[(12.6～2.43)×106]IU/ml(中位值2.54×104IU/ml)。36份进行基因分型的标本包括47.2%基因1型、5.6%基因2型、19.4%基因3型和27.8%基因6型。慢性感染组标本的年龄及抗-HCV水平(S/CO值)显著高于病毒自然清除和假阳性组(χ2=7.812,P<0.05;χ2=90.865,P<0.01)。结论深圳地区献血者HCV感染病毒自然清除率约为46.9%。HCV基因型中1型为主要,6型也占有较高比例。年龄小、女性献血者更易于自然清除病毒。病毒血症即慢性感染者HCV抗体水平显著升高,其在HCV自然康复过程中的作用还有待进一步研究。

Objective To determine the ratio of recovery hepatitis C virus （HCV） infection,to understand HCV genotype distribution and to explore the characterization of HCV recovery and chronic infection in .blood donors from Guangdong. Methods Antibody reactive serums confirmed by at least two anti-HCV EIAs were tested for viral load by QPCR, confirmed by RT-Nested PCR, and then classified into three statuses of recovery （ RNA-/Ah ＋ ）, chronic （ RNA ＋/Ab ＋ ） and false positive infections （RNA-/Ab-）. Data analysis was performed among three HCV infection statuses regarding to clinical information （gender and age）, ALT level and anti-HCV activity. HCV phylogenetie analyses were also performed by 5＇-NCR genotyping. Results 152 index plasma samples were stratified into 45 recovered,51 chronic and 56 false positive HCV infections. Viral loads of 50 HCV plasmas ranged between 12.6 IU/ml and 2.43×10^6 IU/ml （ median 2.54×10^4 IU/nll）. Genotypes 1 （47.2%） ,2 （5.6%） ,3 （ 19. ,1% ） and 6 （27.8%） of 38 HCV strains were identified phylogenetieally. Chronic donors were significantly older,bad higher levels of anti-HCV activity （S/CO value） than recovery and false positive HCV infected donors （χ^2 =7.812,P〈0.05;χ^2 =90. 865,P 〈0. 01,respectively）. Conclusion The spontaneous reeovery rate is 46.9% of blood donors in Guangdong. HCV genotype 1 was dominant and genotype 6 is also prevalent. Younger and female donors seem easier to be recovered from HCV infection. Elevated anti-HCV antibody activity is observed in chronic donors,whether it played a role in HCV recovery need to be further studied.