深圳献血者中HCV感染自然清除与病毒血症特征分析

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,P0.05;χ2=90.865,P0.01)。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。

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

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-/Ab+),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 phylogenetic 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 2.43×106 IU/ml(median 2.54×104 IU/ml).Genotypes 1(47.2%),2(5.6%),3(19.4%) and 6(27.8%) of 38 HCV strains were identified phylogenetically.Chronic donors were significantly older,had higher levels of anti-HCV activity(S/CO value) than recovery and false positive HCV infected donors(χ2=7.812,P<0.05;χ2=90.865,P<0.01,respectively).Conclusion The spontaneous recovery 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.