Zbinden Andrea, Ries Judith, Redli Patrick M, Shah Cyril, Glauser Andreas, Goslings David, Huzly Daniela, Böni Jürg, Gottschalk Jochen, Frey Beat M
Institute of Medical Virology, University of Zurich, Zurich, Switzerland.
Blood Transfusion Service SRC Zurich, Swiss Red Cross, Zürich, Switzerland.
Transfus Med Hemother. 2022 Jul 6;49(6):338-345. doi: 10.1159/000525480. eCollection 2022 Dec.
Screening of hepatitis B surface antigen (HBsAg) and individual-donation nucleic acid amplification testing (ID-NAT) of blood donors have become standard to detect hepatitis B virus (HBV) infection. However, there is still a residual risk of HBV transmission by blood components of donors suffering from occult HBV infection (OBI). Therefore, many countries implemented universal testing of anti-HBV core antigen (anti-HBc) antibodies in order to increase blood safety. In Switzerland, anti-HBc testing is not part of the routine blood donor-screening repertoire. Therefore, we sought to assess prevalence of donors with OBI in a Swiss blood donor collective.
Blood donations were prospectively investigated for the presence of anti-HBc antibodies during two time periods (I: all donors, March 2017; II: first-time donors only, April 2017 until February 2018). Anti-HBc-positive findings were confirmed by an anti-HBc neutralization test. Discarded plasma samples of anti-HBc-confirmed positive donors were ultracentrifuged and subsequently retested by regular HBV-ID-NAT to search for traces of HBV.
During time period I, 78 (1.6%) individuals out of 4,923 donors were confirmed anti-HBc-positive. Sixty-nine (88%) anti-HBc-positive samples were available and processed by ultracentrifugation followed by repeat HBV-ID-NAT. Four samples (5.8%) were found positive for HBV DNA. Sixty-five (94.2%) samples remained HBV NAT-negative upon ultracentrifugation. During time period II, 56 (0.9%) donor samples out of 6,509 exhibited anti-HBc-confirmed positive. Fifty-five (98%) samples could be reassessed by HBV-ID-NAT upon ultracentrifugation. Three (5.5%) samples contained HBV DNA and 52 (94.5%) samples remained HBV NAT-negative.
Overall, we detected 7 viremic OBI carriers among 11,432 blood donors, which tested negative for HBV by standard HBV-ID-NAT and HBsAg screening. In contrast, OBI carriers showed positive anti-HBc findings which could be confirmed in 83.8% of the cases. Thus, OBI might be missed by the current HBV screening process of Swiss blood donors. We suggest to review current HBV screening algorithm. Extended donor screening by anti-HBc testing may unmask OBI carriers and contribute to blood safety for the recipient of blood products.
对献血者进行乙型肝炎表面抗原（HBsAg）筛查和个体献血核酸扩增检测（ID-NAT）已成为检测乙型肝炎病毒（HBV）感染的标准方法。然而，隐匿性HBV感染（OBI）献血者的血液成分仍存在HBV传播的残余风险。因此，许多国家实施了抗HBV核心抗原（抗-HBc）抗体的普遍检测，以提高血液安全性。在瑞士，抗-HBc检测并非常规献血者筛查项目的一部分。因此，我们试图评估瑞士献血人群中OBI献血者的患病率。
在两个时间段前瞻性调查献血样本中抗-HBc抗体的存在情况（时间段I：2017年3月所有献血者；时间段II：仅首次献血者，2017年4月至2018年2月）。抗-HBc阳性结果通过抗-HBc中和试验进行确认。对抗-HBc确认阳性献血者的废弃血浆样本进行超速离心，随后通过常规HBV-ID-NAT重新检测，以寻找HBV痕迹。
在时间段I中，4923名献血者中有78人（1.6%）抗-HBc确认阳性。69份（88%）抗-HBc阳性样本可供使用，并进行超速离心处理，随后重复进行HBV-ID-NAT检测。4份样本（5.8%）HBV DNA检测呈阳性。65份样本（94.2%）超速离心后HBV NAT检测仍为阴性。在时间段II中，6509份献血者样本中有56份（0.9%）抗-HBc确认阳性。55份样本（98%）超速离心后可通过HBV-ID-NAT重新评估。3份样本（5.5%）含有HBV DNA，52份样本（94.5%）HBV NAT检测仍为阴性。
总体而言，在11432名献血者中，我们检测到7名病毒血症OBI携带者，这些献血者通过标准HBV-ID-NAT和HBsAg筛查HBV检测呈阴性。相比之下，OBI携带者抗-HBc检测结果呈阳性，其中83.8%的病例可得到确认。因此，瑞士献血者目前的HBV筛查流程可能会遗漏OBI携带者。我们建议审查当前的HBV筛查算法。通过抗-HBc检测扩大献血者筛查范围，可能会发现OBI携带者，从而提高血液制品受血者的血液安全性。
