NAT技术在德宏地区献血标本输血传染病筛检中的应用

目的应用NAT技术对德宏地区献血标本进行病毒核酸检测,探讨NAT技术对缩短ELISA法检测HIV、HBV和HCV"窗口期"、防范病毒变异与静默感染漏检的作用。方法采用ELISA和NAT检测技术同步对献血标本分别进行HBsAg、抗-HCV、抗-HIV和HBV DNA、HCV RNA、HIV-1RNA检测,对ELISA方法检测阴性NAT检测阳性的献血者进行追踪。结果 14 233例ELISA检测阴性献血者标本中NAT联检阳性14例,鉴别试验HBV DNA阳性12例,未能鉴别病毒种类2例,未检出HIV-1RNA、HCV RNA阳性。对HBV DNA阳性献血者进行1～3次追踪确认,发现1例为HBV"窗口期"感染,11例为OBI感染。结论血站实施病毒NAT筛检能进一步提高血液的安全性。     

核酸检测技术在襄阳地区献血筛查中的应用分析

目的 评估核酸检测技术(NAT)应用于献血者血液筛查的必要性和可行性.方法 采用上海浩源生物科技公司乙型肝炎病毒、丙型肝炎病毒、人类免疫缺陷病毒(1型)核酸检测试剂盒(PCR-荧光法),对2011年8月～2012年5月本血站ELISA检测合格的献血者36 678人份血液标本进行HBV DNA、HCV RNA和HIV RNA-1项联合检测,先对8人份混样标本进行检测,如为非反应性,则该合并检测池中的标本均为非反应性,如合并检测呈反应性,再进行拆分检测.本试剂盒合并和拆分检测使用相同的复合PCR扩增系统,单管实时荧光PCR检测3种病原体,通过将探针标记不同的荧光信号分辨HBV、HCV、HIV-1反应性病原体种类.结果 对36 678人份ELISA法检测抗-HIV、抗-HCV、HBsAg均为阴性的合格血液标本共检测出HBV DNA阳性57例,阳性率为0.16％;未检测出HCV RNA和HIV RNA.结论 NAT能在ELISA检测阴性的献血者血液标本中筛查到HBV、HCV和HIV-1反应性的标本,常规开展NAT能进一步提高血液及输血安全.     

核酸扩增技术在献血者血液筛查中的应用分析

目的探讨核酸扩增技术在献血者血液筛查中的应用价值。方法采用HBV/HCV/HIV核酸检测试剂对血站常规ELISA筛查阴性的献血者标本进行HBV DNA、HCV RNA和HIV-1RNA 3个项目的8人份汇集检测,阳性汇集池再拆分检测。结果 33 714份ELISA筛查阴性标本中,检出HBV DNA阳性标本5例,阳性检出率为0.015%,未检出HCV RNA阳性标本和HIV-1RNA阳性标本。结论核酸扩增技术应用于无偿献血者血液筛查,有助于提高献血者的血液质量,保证输血安全。     

核酸检测技术在无锡市献血筛查中的应用分析

目的：评估核酸检测技术（Nucleic Acid Technology ,NAT）应用于献血者血液筛查的必要性和可行性。方法采用美国罗氏诊断公司乙型肝炎病毒、丙型肝炎病毒、人类免疫缺陷病毒（1型＋2型）核酸联合检测试剂盒（PCR‐荧光法）,对2013年4月～7月本血站ELISA检测合格的献血者9418例血液标本进行 HBV DNA、HCV RNA和 HIV RNA1＋2联合检测,先对6人份混样标本进行检测,如为非反应性,则该合并检测池中的标本均为非反应性,如合并检测呈反应性,再进行拆分检测。本试剂盒合并和拆分检测使用相同的复合PCR扩增系统,单管实时荧光 PCR检测3种病原体,通过将探针标记不同的荧光信号分辨HBV、HCV、HIV‐1＋2反应性病原体种类。结果对9418人份ELISA检测 HBsAg、抗‐HCV、抗‐HIV均为阴性的合格血液标本共检测出HBV DNA阳性6例,阳性率为0．06％;HCV RNA阳性1例,阳性率为0．01％,HCV RNA阳性血液病毒定量为4．27×106 IU／mL ;未检测出HIV RNA。结论 NAT能在ELISA检测阴性的献血者血液标本中筛查到HBV、HCV反应性的标本,常规开展NAT能进一步提高血液及输血安全。     

我国5城市合格献血者血液HIV及HCV残余风险研究

目的研究我国献血者血液HIV及HCV残余风险;评估我国开展血液核酸检测(NAT)的可行性和必要性。方法采集乌鲁木齐、昆明、北京、广州、杭州5城市献血者血样,用Chiron Procleix HIV-1/HCV Assay血液核酸检测体系,对各项血清学筛查均合格的89 467份血液作16人份混合血样NAT检测,凡筛查不合格血样再作单人份检测;对于抗-HCV阴性而HCV RNA NAT阳性者,用备用管作抗-HCV、ALT、及HCV RNA NAT复检。结果共检出HCV RNA NAT阳性但抗-HCV EIA阴性标本3例,未检出HIV RNA NAT阳性但抗-HIV EIA阴性标本;在87 034份血清学筛查合格献血者中,检出HCV NAT阳性2例,其中1例复检ALT为254U/L,未检出HIVNAT阳性;在2 613份血清学筛查不合格者中,检出1例HCV NAT阳性但抗-HCV EIA阴性标本,该献血者抗-HIV阳性、ALT 372U/L;未检出HIV NAT阳性但抗-HIV EIA阴性的标本。结论血清学筛查使我国的血液安全性已有相当高的保障;而NAT技术可进一步提高血液的安全性,但在我国是否可应用于常规血液筛查,需考虑成本与效益比。此外,ALT筛查对排除抗-HCV漏检血液仍有一定的作用。     

一例抗-HCV阴性、HCVRNA阳性献血者的追踪随访

目的追踪随访1例抗-HCV阴性、HCV RNA阳性的献血者,观察其血清学何时发生阳性转换并确认其"窗口期"。方法采用罗氏Cobas’s201系统和科华核酸筛查系统对ELISA检测HBs Ag、抗-HCV和抗-HIV1/2为阴性的无偿献血者标本,进行HBV/HCV/HIV联合核酸定性检测。先进行混样检测,再对阳性的混合标本进行单检。对ELISA阴性、NAT阳性的献血者再进行追踪随访。结果从ELISA筛查阴性的247 936份标本中检出125例(1/1 983)NAT阳性标本,其中有1例抗-HCV阴性、HCV RNA阳性的献血者,追踪随访之后发现第6周时献血者抗-HCV完全转为阳性。结论 NAT应用于献血者血液筛查有助于缩短HCV检出"窗口期",有效地阻断了丙肝"窗口期"感染的血液传播。开展NAT在保障临床输血安全方面有重要的意义,应积极推广。     

核酸检测技术在献血者血液筛查中的应用

目的评估核酸检测技术(NAT)应用于献血者血液筛查的必要性和可行性。方法采用美国罗氏诊断公司cobas s 201系统对2010年8月～2011年12月血站ELISA检测合格的献血者79 414人份血液标本进行HIVRNA-1,-2、HCV RNA和HBV DNA 3项联合核酸检测(cobas TaqScreen MPX试剂),先对6人份标本混样进行NAT,如为阴性,则直接出具结果,如出现阳性结果,再进行拆分检测;对NAT检测反应性标本进行分项确证试验。结果ELISA法共检测了98 935人份标本,抗-HIV、抗-HCV、HBsAg均为阴性的合格血液共96 923份;对79 414人份血液标本NAT共检出阳性194例,阳性率为0.24%;分项检测发现127例阳性标本,病毒类型均为HBV DNA,未检测出HCV RNA和HIV RNA,阳性检出率为65.46%(127/194)。结论 NAT能在ELISA检测阴性的献血者血液标本中筛查到HIV RNA-1,-2、HCV RNA和HBV DNA反应性标本,常规开展NAT能进一步提高血液及输血安全。     

核酸检测与酶免检测在郑州地区血液筛查中的联合应用

目的探讨NAT和ELISA联合应用于郑州地区血液筛查的意义。方法 184 095份标本(酶免检测双试剂阳性除外)采用2种核酸检测系统进行HBV DNA/HCV RNA/HIV RNA检测,并对ELISA阴性、NAT阳性标本进行鉴别试验、血清学补充实验和追踪随访。结果核酸试剂1共检测了98 371例标本,检出63例NAT阳性标本,NAT阳性率为0.06%;其中49例经鉴别确认,检出率分别为59.18%(29/49)、69.39%(34/49),其差异无统计学意义(P0.05),14例未鉴别。核酸试剂2共检测了85 724例标本,检出28例HBV DNA+、1例HCV RNA+,NAT阳性率为0.03%;其中22例经鉴别确认,检出率分别为72.73%(16/22)、63.64%(14/22),其差异无统计学意义(P0.05),7例标本未鉴别。2厂家核酸试剂的拆分阳性率和NAT阳性率相比较差异均有统计学意义(P0.05)。追踪随访3例ELISA阴性、NAT阳性的献血者,确定2例为阴性,1例为HCV感染者。结论在血液筛查中,应用不同厂家NAT试剂能形成互补减少ELISA的漏检,有效地预防经输血传播病毒性疾病。将NAT阳性标本送检做鉴别确认,对NAT实验室的检测能力起到一定监控作用。     

多重定量PCR法同步检测HBV、HCV和HIV-1在血液筛查中的优化及应用

目的 初步探讨多重定量聚合酶链反应（PCR）同步检测乙型肝炎病毒（HBV） DNA,丙型肝炎病毒（HCV） RNA及人类免疫缺陷病毒（HIV）-1 RNA在血液筛查中的应用前景.方法 选择2012年8月至12月,于孝感市中心血站志愿献血的合格献血者血样中,经2次酶联免疫吸附法（ELISA）检测HBV表面抗原（HBsAg）、抗HCV及抗HIV-1,检测结果均呈阴性的4 800份血样为研究对象.采用全自动核酸混合提取仪对该4 800份血样进行核酸提取,然后利用多重定量PCR方法对血样中HBV、HCV及HIV-1进行同步扩增检测.采用中国药品和生物制品检定所提供的HBV DNA、HCV RNA及HIV-1 RNA标准参考品,检测多重定量PCR的灵敏度,并与单重定量PCR的灵敏度进行比较.在HBV、HCV及HIV-1 3者中任意1种病毒基因组浓度较高的条件下,对多重定量PCR检测另2种低浓度病毒基因组的能力进行评估.结果 增加多重定量PCR中c-MMLV逆转录酶和Hot Taq酶的用量,并适量加入单链结合蛋白（SSB）,可使其扩增效率提升至单重定量PCR扩增水平.本组4 800份血样中,经多重定量PCR检测出3份HBV DNA阳性样品,ELISA漏检率为0.062 5％,未发现HCV RNA和HIV-1 RNA阳性样品;多重定量PCR检测HBV DNA、HCV RNA及HIV-1 RNA在95％置信区间的灵敏度浓度分别为115 IU/mL、376 IU /mL和232 IU /mL;单重定量PCR检测HBV DNA、HCV RNA和HIV-1 RNA在95％置信区间的灵敏度浓度分别为51 IU /mL、94 IU /mL和78 IU/mL.结论 本研究初步建立了对献血者血液同时进行HBV DNA、HCV RNA及HIV-1 RNA检测的多重定量PCR检测方法;该检测体系经过进一步优化后,有望应用于临床大规模血液病毒筛查.     

常州市中心血站HBV筛查中酶联免疫检测与核酸检测结果不一致的分析

目的:调查常州地区无偿献血者HBV筛查中ELISA HBsAg阴性/核酸扩增检测(nu c l e i c ac i d amplification detection technology,NAT)HBV DNA阳性的情况,确保输血安全。方法:经2种不同的ELISA试剂检测合格的献血者标本,采用罗氏或者科华核酸检测系统检测HBV DNA,HCV RNA,HIV RNA的6人份混合样本(POOL),混样阳性的POOL再进行拆分检测,采用化学发光的方法对拆分阳性的标本检测乙肝标志物5项,并对所检出乙肝标志物5项结果全为阴性的血液进行追踪。结果:48 635份2遍ELISA阴性的献血者标本混检11 016个POOL,混检阳性的POOL数为66个,经拆分为HBV DNA阳性的POOL数为40个,未检出HCV RNA和HIV RNA,NAT总有效拆分率为60.61%,NAT检测出的标本阳性率为0.08%。针对上述HBV DNA阳性的血液,用化学发光再次检测乙肝5项,有7份标本五项全阴;其余为6份抗-HBs+、6份抗-HBs+/抗-HBc+、4份抗-HBs+/抗-HBe+、7份抗-HBc+/抗-HBe+、10例抗-HBc+。追踪其中4份乙肝5项检测结果全阴的血液,HBsAg均由阴性转为阳性。结论:NAT能在ELISA阴性的标本中筛检出HBV DNA阳性的标本,减少窗口期乙肝和隐匿性乙肝的发生,进一步保证了血液的安全。ELISA HBsAg阴性/NAT HBV DNA阳性的献血者中以隐匿性乙肝为主,为输血残余风险的主要隐患。     

全自动血液核酸筛查及阳性献血员追踪的研究

目的 建立献血者全自动核酸检测方法，探讨在我国血液筛查中引进全自动核酸筛查方法的可行性。方法 在酶联免疫吸附实验（ELISA）筛查血液基础上，选用全自动汇集仪进行血样汇集（24人份），在全自动核酸提取仪上提取样本核酸，应用聚合酶链反应（PCR），在COBAS AMPLICOR进行扩增和检测结果，用国际标准核酸质控品考评检出限量，对阳性献血者追踪检测。结果经考评及常规应用表明，全自动汇集、全自动核酸提取及扩增和检测95％的检出限量HBV DNA、HCV RNA和HIV-1 RNA分别为38．9、17．4IU／ml和20．6拷贝／ml，95％的可信限分别为[21，323]、[10．5，342]和[12，300]。通过对16512个样本共688汇集池分析，HBVDNA阳性8例，阳性率为0．048％，其中7例为Anti-HBc阳性，其余1例亦转换为阳性。HCV RNA和HIV-1 RNA未检出阳性，6例HBV DNA阳性样本追踪发现，3例发生了血清转换现象。结论本实验结果认为全自动血样汇集，全自动核酸提取扩增和检测方法可应用于血液的筛查工作。     

上海地区无偿献血者乙肝病毒核酸检测分析

目的了解无偿献血者乙肝病毒核酸筛查(NAT)阳性人群特点,为血液安全策略提供参考。方法无偿献血者血液经Murex和科华HBsAg ELISA试剂检测,结果为阴性的血液使用cobas TaqScreen MPX试剂进行HBV DNA,HCV RNA,HIV RNA 3项联合核酸检测。对于MPX反应性标本,使用COBAS AmpliPrep/TaqMan进行核酸鉴别试验,同时使用罗氏ECL电化学发光检测系统进行乙肝补充血清学试验。结果 2011年11月1日～2012年1月31日3个月共有献血者86 375人(次),其中有63 351人(次)为初次献血者,HBsAg反应性为1.04%,23 024人(次)为重复献血者,HBsAg反应性为0.46%,两者差异有统计学意义(χ2=63.63,P0.05)。84 990份HBsAg、抗-HCV、抗-HIV1/2阴性血液进行MPX核酸检测,共发现52例(0.060%)HBV DNA阳性,均为低拷贝,含量为(20～200)IU/ml间,其中32例(0.051%)来自初次献血者,20例(0.087%)来自重复献血者,两者比例差异无统计学意义(χ2=3.65,P0.05),没有发现HCV RNA与HIV RNA阳性。结论重复献血者HBsAg反应性比率低于初次献血者;HBsAg阴性献血者HBV DNA阳性率为0.060%,重复献血者HBV DNA阳性率与初次献血者比较,两者差异无统计学意义;开展HBV核酸检测能够进一步保障血液安全。     

免疫筛查阴性献血者血样病毒核酸检测的研究

目的了解二次酶联免疫筛查献血者血样漏检的原因。方法将二次酶联免疫筛查阴性的献血者血样在加样仪上实现血液样本汇集,用全自动核酸提取仪提取样本核酸,以核酸扩增检测仪做HBV、HCV和HIV自动扩增检测。对HBsAg阴性、HBVDNA阳性献血者用核酸筛查试剂定量检测HBV,并每隔2周对其跟踪采血,做HBV两对半免疫检测和HBsAgV3的确认试验。结果16320份二次酶联免疫筛查阴性的合格献血者血样中,8份HBVDNA阳性(漏检率0.49‰),未发现HCV和HIV1RNA阳性。8份HBVDNA阳性献血者乙肝两对半免疫检测HBsAg、HBsAb和HBeAg均为阴性,HBcAb均为阳性,3份HBeAb为阳性。6例HBsAg阴性HBVDNA阳性献血者血样的病毒滴度在(76～1490)copies/ml,2例病毒滴度过低,未定量检测到病毒。跟踪6名HBVDNA阳性献血者,1例18周时HBsAg确认试验阳性,其余5例仍为阴性。结论现行的二次酶联免疫技术的血液筛查存在HBV漏检,原因可能是隐匿性乙型肝炎病毒感染。应重视血液筛查工作中HBV的漏检及输血传播,并在现有的血液筛查模式中或增加HBcAb检测,或增加病毒核酸筛查。     

HBsAg阴性献血者人群HBV感染的检测和输血残余风险分析

目的 了解献血人群乙型肝炎病毒(HBV)感染状况和血液经酶免疫法(EIA)筛查乙型肝炎病毒表面抗原(HBsAg)后经血传播HBV感染的残余风险.方法 采用国产和进口两种EIA试剂对献血者血液进行HBsAg筛查,罗氏诊断COBAS Ampliscreens NAT血筛系统检测EIA检测合格标本中HBV DNA,对HBV DNA阳性标本进行半套式PCR检测,并对PCR扩增产物进行测序和病毒基因亚型分析.结果 共筛查1998～2008年的献血者232 305例,发现HBsAg阳性2 999例,阳性率为1.3%;对2002～2007年EIA检测合格的113 639例献血者血液标本进行NAT检测,检测出13份HBV DNA阳性、HBsAg阴性的献血者血液,HBV残余风险高达1.1/10 000.结论 EIA筛查后血液安全性有了很好的保障,经血传播HBV残余风险依然处于较高的水平,NAT应用对提高血液安全,降低输血传播HBV残余风险意义重大.     

Two HBV DNA+/HBsAg− blood donors identified by HBV NAT in Shenzhen, China

Background

In order to further improve blood safety, mini-pool (MP) nucleic acid testing (NAT) was implemented to screen samples negative for hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (anti-HCV), anti-human immunodeficiency virus (anti-HIV), syphilis (anti-Treponemal antibody) and with normal ALT.

Study design and methods

From August 2006 to February 2008, 41,301 donations were screened using commercial HIV/HCV RNA and HBV DNA Real-Time PCR NAT assays in pools of 8. Reactive pools were re-tested as individual samples using the appropriate screening test and confirmed using an alternate commercial NAT assay. Donors reactive on both NAT assays were considered ‘confirmed’ positive for the virus concerned and recalled for additional follow-up testing and counseling.

Results

Of the 41,301 samples screened, no HIV or HCV RNA-positive/seronegative donations were detected but two HBV DNA positive/HBsAg negative blood donors (Donors 1 and 2) were identified. Their respective hepatitis immunological markers were: Donor 1 - anti-HBc positive/anti-HBe positive/HBeAg negative/ALT normal and HBV DNA viral load of 112 IU/ml; Donor 2 - anti-HBc positive/anti-HBe negative/HBeAg negative/ALT normal and HBV DNA viral load 2750 IU/ml.

Conclusions

MP NAT identified two HBsAg negative donors with presumed occult infection but no HIV or HCV seronegative/NAT positive (yield) donors. The HBV yield rate of 1 in 20,650 (95%CI - 1 in 5663 to 1 in 75,303) is comparatively high, exceeds the predicted rate based on previous modeling for the population and demonstrates the incremental blood safety value of NAT in countries where HBV is highly epidemic. The low viral load of the two yield samples underscores the importance of optimizing the sensitivity of the HBV NAT assay selected for screening.     

Impact of individual-donation nucleic acid testing on risk of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus transmission by blood transfusion in South Africa

BACKGROUND: In 2005, the South African National Blood Service introduced individual-donation (ID) nucleic acid test (NAT) screening for human immunodeficiency virus (HIV) RNA, hepatitis C virus (HCV) RNA, and hepatitis B virus (HBV) DNA. At the same time the use of ethnic origin to prioritize the transfusion of blood according to a hierarchy of residual risk was discontinued.
STUDY DESIGN AND METHODS: ID-NAT (Ultrio on Procleix Tigris, Chiron) and serology (PRISM, Abbott) repeat test and confirmation testing algorithms were designed to enable differentiation between false-positive and true-NAT and -serology yields. After 1 year, the NAT and serology yield rates in first-time, lapsed, and repeat donors were analyzed and used to estimate the residual risk of HIV, HBV, and HCV infections by blood transfusion.
RESULTS: The HIV, HBV, and HCV ID-NAT window phase yield rates in 732,250 blood donations were 1:45,765, 1:11,810, and 1:732,200, respectively. Seven of 16 HIV window phase donations with viral loads above 16,000 copies/mL were HIV p24 antigen enzyme-linked immunosorbent assay positive. PRISM detected anti-HIV and hepatitis B surface antigen (HBsAg) in 89.4 and 73.9% of early infections in repeat donors. The Procleix assay detected viremia in 99.7 and 95.5% of anti-HIV– and HBsAg-positive first-time donors. In these donors, the occult HBV DNA carrier rate was 1:5200. The residual transmission risk of ID-NAT HIV, HBV, and HCV window phase donations was estimated at 1:479,000, 1:61,500, and 1:21,000,000 respectively.
CONCLUSION: One-year ID-NAT screening of 732,250 donations interdicted 16 HIV, 20 HBV, and 1 HCV window phase donations and 42 anti-hepatitis B core antigen–reactive infections during an early recovery or a later stage of occult HBV infection.     

单检及16份混样检测模式对献血者核酸检测效果的比较研究

目的 探讨单份及16份混合标本2种检测模式对献血者血液病毒核酸检测(nucleic acid test,NAT)效果的影响.方法 2009年2至6月顺序留取北京无偿献血者标本,用诺华Procleix ULTRIO Assay进行单份(ID)或16份混合标本(P16)乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)和人类免疫缺陷病毒-1( HIV-1)三项联合核酸检测.单份NAT反应性同时HBsAg、抗-HCV或抗-HIV血清学不合格的标本,血清学合格的单份NAT反应性经双孔NAT复检阳性的标本,以及混合NAT反应性/拆分NAT为阳性的标本,进一步用诺华Procleix HBV、HCV和HIV-1鉴别试剂进行鉴别试验.血清学合格、HBV NAT单独阳性标本进一步用Roche HBV定量实验加以验证和进行病毒含量测定、血清学分析、并进行稀释以模拟是否能被P16-NAT检出.阳性检出率进行四格表连续校正的x2检验.结果 (1)在7613份单份NAT (ID-NAT)标本中,检出NAT阳性26份,ID-NAT阳性率0.34％(26/7613)；(2)在16 064份共1004份P16混合标本NAT(P16-NAT)中,检出NAT阳性27份,P16-NAT阳性率为0.17％ (27/16 064)；(3)在血清学合格标本中,单份检测的NAT单独阳性检出率为0.12％ (9/7438),高于16份混样检测的NAT单独阳性检出率0.01％ (2/15 750)(x2=11.880,P＜0.05).9份ID-NAT及2份P16-NAT单独阳性标本经鉴别均为HBV NAT阳性,未检出 HCV NAT单独阳性或HIV NAT单独阳性；(4)9份ID-NAT HBV单独阳性血样模拟P16-NAT,仅有2份可被检出；(5)对8份ID-NAT及2份P16-NAT单独阳性标本进行Roche HBV定量测定,均可确证其核酸检测结果,但病毒含量很低.其中2份HBV病毒含量为472 IU/ml及15 IU/ml,6份含量＜12 IU/ml,另2份原倍不能定量经10倍浓缩处理后测得含量为＜ 12 IU/ml和14.3 IU/ml;(6)11份HBV NAT单独阳性标本中,3份(27.3％)为潜在的窗口期感染,其余8份(72.7％)抗-HBc阳性或抗-HBe阳性,但抗-HBc-IgM均为阴性,为隐匿性感染；(7) P16-NAT初检呈反应性需要进行拆分试验的混合样本比率为2.49％ (25/1004),其中由血清学合格标本所致初检反应性的混合样本比率为0.20％ (2/1004).结论 ID-NAT单独阳性检出率高于P16-NAT单独阳性检出率.为避免低病毒含量HBV的漏检,应选用灵敏度高的核酸检测试剂,并尽量采用小标本量混合检测,甚至采用单份检测方式.     

Impact of nucleic acid testing for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus on the safety of blood supply in Italy: a 6-year survey

BACKGROUND: Nucleic acid testing (NAT) for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) has been implemented in several European countries and in the United States, while hepatitis B virus (HBV) NAT is still being questioned by opinions both in favor and against such an option, depending on the HBV endemicity, health care resources, and expected benefits. STUDY DESIGN AND METHODS: This survey was aimed to assess the NAT impact in improving the safety of blood supply in Italy, 6 years after implementation. The study involved 93 Italian transfusion centers and was carried out in 2001 through 2006. A total of 10,776,288 units were tested for the presence of HCV RNA, 7,932,430 for HIV RNA, and 3,405,497 for HBV DNA, respectively. RESULTS: Twenty‐seven donations or 2.5 per million tested were HCV RNA–positive/anti‐HCV–negative; 14 or 1.8 per million units tested were HIV RNA–positive/anti‐HIV–negative; and 197 or 57.8 per million donations tested were HBV DNA–positive/hepatitis B surface antigen–negative. Of the latter, 8 (2.3/10⁶) were collected from donors in the window phase of infection and 189 (55.5/10⁶) from donors with occult HBV. Sixty‐eight percent of the latter donors had hepatitis B surface antibody, 74.5 percent of whom with concentrations considered protective (≥10 mIU/mL). CONCLUSION: NAT implementation has improved blood safety by reducing the risk of entering 2.5 HCV and 1.8 HIV infectious units per million donations into the blood supply. The yield of NAT in detecting infectious blood before transfusion was higher for HBV than for HCV or HIV. However, the benefit of HBV NAT in terms of avoided HBV‐related morbidity and mortality in blood recipients needs to be further evaluated.     

Blood donation screening for hepatitis B virus markers in the era of nucleic acid testing: are all tests of value?

BACKGROUND: The American Red Cross implemented hepatitis B virus (HBV) minipool (MP)‐nucleic acid testing (NAT) in June 2009, in addition to existing tests for hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B core antigen (anti‐HBc). The value of all three tests was evaluated. STUDY DESIGN AND METHODS: HBsAg, anti‐HBc, and HBV DNA (Ultrio MP‐NAT, Gen‐Probe/Novartis) donation results were analyzed during a 12‐month period (July 1, 2009‐June 30, 2010). Additional testing by individual‐donation (ID) polymerase chain reaction (PCR) to confirm donor infection was performed when any HBV screening test was reactive or positive, except in the case of HBsAg neutralization‐positive, anti‐HBc–reactive samples. Numbers of blood donations identified as reactive or positive versus nonreactive or negative were compared. RESULTS: Of about 6.5 million donations, 699 were defined as from HBV‐infected donors, of which 64% (444) were reactive for all three markers. More than 99% (697) had reactivity to one or both serologic tests with 68% (477) showing reactivity by MP‐NAT. Only two donations were DNA‐positive, seronegative NAT‐yield donations (1 per 3.23 million), fewer than expected (p = 0.0075). Among MP‐NAT–reactive donors, only small numbers represented early infection (2 or 0.4% with negative serology and 10 or 2.1% who were HBsAg confirmed positive, anti‐HBc nonreactive). Of the 142 occult HBV‐infected donors, 85% were MP‐NAT nonreactive requiring ID‐PCR for detection (121 or 54.5% of all MP‐NAT nonreactives vs. 21 or 4.4% of all MP‐NAT reactives). CONCLUSIONS: The HBV DNA–positive yield rate from MP‐NAT was lower than expected, likely representing the rarity of such findings even in very large studies. With the implementation of HBV MP‐NAT, the value of maintaining anti‐HBc for the detection of low‐level HBV DNA–positive donors was confirmed; however, HBsAg screening showed no blood safety value.     

Testing of individual blood donations for HCV RNA reduces the residual risk of transfusion-transmitted HCV infection

BACKGROUND: To allow cost-effective RNA testing with NAT techniques, the national authorities of several countries have planned or already introduced tests of mixed specimens, that is, plasma pools. STUDY DESIGN AND METHODS: High-throughput extraction, amplification, and detection of HCV RNA from individual blood donations were optimized and validated. The feasibility of the method and the frequency of anti-HCV-negative, HCV RNA-positive donations were determined in a prospective study of 27,745 allogeneic and 792 autologous individual donations. RESULTS: The 50- and 95-percent detection limits of the method were determined at 44 IU per mL and 162 IU per mL, respectively (World Health Organization HCV reference material). When 201 HCV RNA-positive sera were taken as a reference, the sensitivity was 97.5 percent. The assay specificity was determined at 99.77 percent. During a 20-month period, two seronegative blood donors tested positive in HCV PCR. The viral load of these donations was 6 x 10(6) and 3 x 10(7) copies per mL, respectively. Thus, the yield of HCV RNA testing in this study was 7. 63 per 100,000 screened donations (95% CI, 1.25-22.07). In both PCR-positive donors, seroconversion was found in subsequent blood samples. CONCLUSION: This study compares the feasibility of single-donation HCV RNA screening, with the detection of a relatively high percentage of window-phase donations, to data reported from groups using HCV RNA testing of plasma pools. The relative yield of NAT of individual donations versus minipools should be directly investigated in the near future.