Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial s...Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial screening tests introduced. The ”first generation“ antibody EIAs detected seroconversion after unduly long infectious window period. Improved HCV antibody assays still had an infectious window period around 66 d. HCV core antigen EIAs shortened the window period considerably, but high costs did not lead to widespread acceptance. A fourth-generation HCV antigen and antibody assay (combination EIA) is more convenient as two infectious markers of HCV are detected in the same assay. Molecular testing for HCV-RNA utilizing nucleic acid amplification technology (NAT) is the most sensitive assay and shortens the window period to only 4 d. Implementation of NAT in many developed countries around the world has resulted in dramatic reductions in transfusion transmissible HCV and relative risk is now < 1 per million donations. However, HCV serology still continues to be retained as some donations are serology positive but NAT negative. In resource constrained countries HCV screening is highly variable, depending upon infrastructure, trained manpower and financial resource. Rapid tests which do not require instrumentation and are simple to perform are used in many small and remotely located blood centres. The sensitivity as compared to EIAs is less and wherever feasible HCV antibody EIAs are most frequently used screening assays. Efforts have been made to implement combined antigen-antibody assays and even NAT in some of these countries.展开更多
Transfusion-transmitted infections including hepatitis B virus(HBV) have been a major concern in transfusion medicine. Implementation of HBV nucleic acid testing(NAT) has revealed occult HBV infection(OBI) in blood do...Transfusion-transmitted infections including hepatitis B virus(HBV) have been a major concern in transfusion medicine. Implementation of HBV nucleic acid testing(NAT) has revealed occult HBV infection(OBI) in blood donors. In the mid-1980 s, hepatitis B core antibody(HBc) testing was introduced to screen blood donors in HBV non-endemic countries to prevent transmission of non-A and non-B hepatitis. That test remains in use for preventing of potential transmission of HBV from hepatitis B surface antigen(HBs Ag)-negative blood donors, even though anti-hepatitis C virus testshave been introduced. Studies of anti-HBc-positive donors have revealed an HBV DNA positivity rate of 0%-15%. As of 2012, 30 countries have implemented HBV NAT. The prevalence of OBI in blood donors was estimated to be 8.55 per 1 million donations, according to a 2008 international survey. OBI is transmissible by blood transfusion. The clinical outcome of occult HBV transmission primarily depends on recipient immune status and the number of HBV DNA copies present in the blood products. The presence of donor anti-HBs reduces the risk of HBV infection by approximately five-fold. The risk of HBV transmission may be lower in endemic areas than in non-endemic areas, because most recipients have already been exposed to HBV. Blood safety for HBV, including OBI, has substantially improved, but the possibility for OBI transmission remains.展开更多
目的基于血液筛查核酸检测反应性献血者的HBV感染的确认,探讨核酸检测反应性献血者的归队策略。方法联合应用自建的高灵敏度核酸检测体系、血液核酸筛查等多种核酸检测(NAT)方法,并结合血清学检测、献血者随访,对核酸检测反应性(NAT-yie...目的基于血液筛查核酸检测反应性献血者的HBV感染的确认,探讨核酸检测反应性献血者的归队策略。方法联合应用自建的高灵敏度核酸检测体系、血液核酸筛查等多种核酸检测(NAT)方法,并结合血清学检测、献血者随访,对核酸检测反应性(NAT-yield)献血者中的HBV感染进行确认和感染状态识别。依据确认的HBV感染血浆样本,比较不同确认方法、确认指标或指标组合对HBV感染确认的效果。结果2010年11月—2021年2月,在血液筛查检出的876位NAT-yield献血者中共确认HBV感染者511人(OBI 451人,急性早期HBV感染者27人,不能确认感染者33人,无感染者30人,不能确认HBV感染者335人)。采用单检系统对混检系统检出的HBV感染血浆进行复测的检出率为96.6%,明显高于混检系统对单检系统检出的HBV DNA反应性(HBV DNA R)组和鉴别试验无反应性(NDR)组的复测检出率(76.4%和55.7%)(P<0.05)。NDR样本在模式2(ID×5+鉴别×2)下复测检出率(65.2%)高于模式1(ID×2+鉴别×1)(39.2%)(P<0.05);2种单检复测模式下的HBV DNA R样本复测检出率无明显差异(P>0.05),但均明显高于NDR样本(P<0.05)。回溯OBI献血者既往NAT数据,有46%经历多次NAT检测而未能检出。有59.1%OBI献血者随访检不出HBV DNA。OBI献血者中抗-HBc+占比为90.2%,单独抗-HBc+为49.2%,远高于不能确认感染组(P<0.05);HBeAg、抗-HBe和抗-HBc IgM在OBI和不能确认感染组中的比例极低且无差异(P>0.05)。结论近60%的NAT-yield献血者可以确认HBV感染。为保证献血者归队的安全性,需要更高灵敏度的HBV DNA确证技术提高HBV感染的确认率。抗-HBc是NAT-yield献血者OBI风险排查和归队评估最重要的血清学指标。展开更多
目的通过分析罗氏Cobas s 201的血液核酸检测(NAT)结果评估其对HBV的检测效果。方法将检测结果根据酶联免疫吸附试验(ELISA)和NAT混合检测(MP)、NAT单样本检测(ID)以及重复NAT单样本检测(rID)分组,分为ELISA+/NAT(ID)+、ELISA+/NAT(rID)...目的通过分析罗氏Cobas s 201的血液核酸检测(NAT)结果评估其对HBV的检测效果。方法将检测结果根据酶联免疫吸附试验(ELISA)和NAT混合检测(MP)、NAT单样本检测(ID)以及重复NAT单样本检测(rID)分组,分为ELISA+/NAT(ID)+、ELISA+/NAT(rID)+、ELISA-/NAT(ID)+、ELISA-/NAT(rID)+4组进行统计分析,探讨重复NAT对反应性结果的检出是否存在差异,对于不同ELISA结果的NAT反应性标本的循环阈值(cycle threshold,Ct)与核酸检出率的关联性。再通过补充试验,包括其他方法学的NAT系统和化学发光血清学标志物检测,进一步分析献血者的真实感染情况。结果766293份献血者标本中共有1691组HBV NAT(MP)+,其中1418组(83.86%)检出反应性结果(1418份HBV NAT+,7090份NAT-),仍有273组(16.14%)经重复检测仍未检出[共计1638份NAT-,Ct(MP):39.49±3.62]。HBV NAT+中,881份(62.13%)ELISA+/NAT(ID)+,19份(1.34%)ELISA+/NAT(rID)+,451份(31.81%)ELISA-/NAT(ID)+,67份(4.72%)ELISA-/NAT(rID)+。对于不同ELISA结果的标本,重复NAT对HBV的检出存在差异(P<0.05)。各组间Ct(ID)值仅ELISA+/NAT(rID)+和ELISA-/NAT(ID)+、ELISA+/NAT(rID)+和ELISA-/NAT(rID)+2组比较无差异(P>0.05),其余各组间两两比较,均有差异(P<0.05)。对228份ELISA-/NAT(MP)+(ID)-进行补充试验,有56份(24.56%)经化学发光检测HBsAg+和7份(3.07%)经其他NAT系统检出反应性。剩余221份(96.93%)NAT-标本中,53份(23.98%)HBsAg+的献血者可能存在慢性感染,40份(18.10%)抗-HBe+和(或)抗-HBc+的献血者可能存在既往感染,其余128份(57.92%)均无反应性的献血者为NAT(MP)假反应性,且各组间抗-HBs含量差异较大(P<0.05)。结论重复NAT对不同反应性类别或不同血清学结果的献血者标本存在差异性检出,尤其在一定区间范围内,对于ELISA-标本进行重复NAT可明显提高检出率。Ct值可辅助评估NAT系统的稳定性和准确性。对于ELISA-/NAT(MP)+(ID)-献血者,结合其他高灵敏度的检测手段可降低病毒残余风险,保障临床用血安全。展开更多
戊型肝炎是一种戊型肝炎病毒(Hepatitis E Virus,HEV)感染后以肝脏损伤为主的急性传染病,主要经粪-口传播,好发于青壮年及中老年人,在孕妇及免疫抑制人群中危害较大。据世界卫生组织(World Health Organization,WHO)统计,全球每年约有2...戊型肝炎是一种戊型肝炎病毒(Hepatitis E Virus,HEV)感染后以肝脏损伤为主的急性传染病,主要经粪-口传播,好发于青壮年及中老年人,在孕妇及免疫抑制人群中危害较大。据世界卫生组织(World Health Organization,WHO)统计,全球每年约有2000万人感染HEV,其中约330万患者出现戊型肝炎症状。近期,通过血源传播而感染HEV的病例受到了广泛关注。经研究发现在全世界的无症状献血者中仅有0.013%~0.281%存在HEV病毒血症,但HEV在非常低的病毒血液浓度下同样具有传染性,并且迄今无特异的治疗药物和方法,所以对献血者进行HEV筛查是必要的。目前HEV筛查政策只在少数国家实施,包括普遍筛查和选择性筛查。而对献血者提供的血液,尚没有明确规定检测HEV感染的标志物。本综述主要通过对比国内外HEV的核酸血液筛查情况探讨其研究进展及必要性。展开更多
文摘Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial screening tests introduced. The ”first generation“ antibody EIAs detected seroconversion after unduly long infectious window period. Improved HCV antibody assays still had an infectious window period around 66 d. HCV core antigen EIAs shortened the window period considerably, but high costs did not lead to widespread acceptance. A fourth-generation HCV antigen and antibody assay (combination EIA) is more convenient as two infectious markers of HCV are detected in the same assay. Molecular testing for HCV-RNA utilizing nucleic acid amplification technology (NAT) is the most sensitive assay and shortens the window period to only 4 d. Implementation of NAT in many developed countries around the world has resulted in dramatic reductions in transfusion transmissible HCV and relative risk is now < 1 per million donations. However, HCV serology still continues to be retained as some donations are serology positive but NAT negative. In resource constrained countries HCV screening is highly variable, depending upon infrastructure, trained manpower and financial resource. Rapid tests which do not require instrumentation and are simple to perform are used in many small and remotely located blood centres. The sensitivity as compared to EIAs is less and wherever feasible HCV antibody EIAs are most frequently used screening assays. Efforts have been made to implement combined antigen-antibody assays and even NAT in some of these countries.
文摘Transfusion-transmitted infections including hepatitis B virus(HBV) have been a major concern in transfusion medicine. Implementation of HBV nucleic acid testing(NAT) has revealed occult HBV infection(OBI) in blood donors. In the mid-1980 s, hepatitis B core antibody(HBc) testing was introduced to screen blood donors in HBV non-endemic countries to prevent transmission of non-A and non-B hepatitis. That test remains in use for preventing of potential transmission of HBV from hepatitis B surface antigen(HBs Ag)-negative blood donors, even though anti-hepatitis C virus testshave been introduced. Studies of anti-HBc-positive donors have revealed an HBV DNA positivity rate of 0%-15%. As of 2012, 30 countries have implemented HBV NAT. The prevalence of OBI in blood donors was estimated to be 8.55 per 1 million donations, according to a 2008 international survey. OBI is transmissible by blood transfusion. The clinical outcome of occult HBV transmission primarily depends on recipient immune status and the number of HBV DNA copies present in the blood products. The presence of donor anti-HBs reduces the risk of HBV infection by approximately five-fold. The risk of HBV transmission may be lower in endemic areas than in non-endemic areas, because most recipients have already been exposed to HBV. Blood safety for HBV, including OBI, has substantially improved, but the possibility for OBI transmission remains.
文摘目的基于血液筛查核酸检测反应性献血者的HBV感染的确认,探讨核酸检测反应性献血者的归队策略。方法联合应用自建的高灵敏度核酸检测体系、血液核酸筛查等多种核酸检测(NAT)方法,并结合血清学检测、献血者随访,对核酸检测反应性(NAT-yield)献血者中的HBV感染进行确认和感染状态识别。依据确认的HBV感染血浆样本,比较不同确认方法、确认指标或指标组合对HBV感染确认的效果。结果2010年11月—2021年2月,在血液筛查检出的876位NAT-yield献血者中共确认HBV感染者511人(OBI 451人,急性早期HBV感染者27人,不能确认感染者33人,无感染者30人,不能确认HBV感染者335人)。采用单检系统对混检系统检出的HBV感染血浆进行复测的检出率为96.6%,明显高于混检系统对单检系统检出的HBV DNA反应性(HBV DNA R)组和鉴别试验无反应性(NDR)组的复测检出率(76.4%和55.7%)(P<0.05)。NDR样本在模式2(ID×5+鉴别×2)下复测检出率(65.2%)高于模式1(ID×2+鉴别×1)(39.2%)(P<0.05);2种单检复测模式下的HBV DNA R样本复测检出率无明显差异(P>0.05),但均明显高于NDR样本(P<0.05)。回溯OBI献血者既往NAT数据,有46%经历多次NAT检测而未能检出。有59.1%OBI献血者随访检不出HBV DNA。OBI献血者中抗-HBc+占比为90.2%,单独抗-HBc+为49.2%,远高于不能确认感染组(P<0.05);HBeAg、抗-HBe和抗-HBc IgM在OBI和不能确认感染组中的比例极低且无差异(P>0.05)。结论近60%的NAT-yield献血者可以确认HBV感染。为保证献血者归队的安全性,需要更高灵敏度的HBV DNA确证技术提高HBV感染的确认率。抗-HBc是NAT-yield献血者OBI风险排查和归队评估最重要的血清学指标。
文摘戊型肝炎是一种戊型肝炎病毒(Hepatitis E Virus,HEV)感染后以肝脏损伤为主的急性传染病,主要经粪-口传播,好发于青壮年及中老年人,在孕妇及免疫抑制人群中危害较大。据世界卫生组织(World Health Organization,WHO)统计,全球每年约有2000万人感染HEV,其中约330万患者出现戊型肝炎症状。近期,通过血源传播而感染HEV的病例受到了广泛关注。经研究发现在全世界的无症状献血者中仅有0.013%~0.281%存在HEV病毒血症,但HEV在非常低的病毒血液浓度下同样具有传染性,并且迄今无特异的治疗药物和方法,所以对献血者进行HEV筛查是必要的。目前HEV筛查政策只在少数国家实施,包括普遍筛查和选择性筛查。而对献血者提供的血液,尚没有明确规定检测HEV感染的标志物。本综述主要通过对比国内外HEV的核酸血液筛查情况探讨其研究进展及必要性。
