Nuffield Department of Medicine, Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK.
Microbiology Services, NHS Blood and Transplant, UK.
Transfus Med. 2022 Oct;32(5):402-409. doi: 10.1111/tme.12893. Epub 2022 Jun 25.
Infections with human parvovirus B19 (B19V) are transmissible by blood components and plasma-derived medicines. The European Pharmacopoeia regulates maximum levels of virus allowed in manufacturers' plasma pools. To evaluate contamination risk prior to re-introduction of UK-sourced plasma for manufacturing, we investigated viraemia frequencies of B19V in plasma samples collected from blood donors before and during COVID-enforced lockdown.
Quantitative PCR for B19V DNA was used to screen pools of 96 anonymised plasma samples collected in England from 2017 (n = 29 505), 2020 (n = 3360) and 2021 (n = 43 200). Selected positive pools were resolved into individual samples. Data on donor notifications and related lookback investigations were collected from European countries by on-line survey in 2020.
Screening of 76 065 donations identified 80 B19V-positive pools. While most positive samples had low viral loads (<10 IU ml ), primarily from 2017 (77/29 505; 0.3%), two contained high levels of B19V DNA (1.3 × 10 and 6.3 × 10 IU ml ), both likely to contaminate a final manufacturer's pool and lead to discard. The incidence of B19V infection during lockdown was reduced (1/3360 in 2020; 0/43 200 in 2021). Genomic analysis of positive pools resolved to single samples identified B19V genotype 1 in all nine samples. Seroprevalence of anti-B19V IgG antibodies was 75% (143/192). A survey of B19V screening practices in Europe demonstrated considerable variability. Two blood establishments informed infected blood donors of positive B19V results.
Information on seroprevalence, incidence and viral loads of B19V viraemia is contributory the evaluation of alternative operational screening strategies for plasma testing.
人类细小病毒 B19（B19V）感染可通过血液成分和血浆衍生药物传播。《欧洲药典》规定了制造商血浆池允许的最大病毒含量。为了评估英国血浆重新用于生产前的污染风险，我们调查了 COVID 强制封锁期间采集的献血者血浆样本中 B19V 的病毒血症频率。
使用定量 PCR 检测 B19V DNA，对 2017 年（n=29505）、2020 年（n=3360）和 2021 年（n=43200）从英格兰采集的 96 份匿名血浆样本进行了筛查。从阳性池中选择了一些样本进行单独分析。2020 年通过在线调查从欧洲国家收集了关于献血者通知和相关回溯调查的数据。
对 76065 份献血样本的筛查发现了 80 个 B19V 阳性池。虽然大多数阳性样本的病毒载量较低（<10 IU/ml），主要来自 2017 年（77/29505；0.3%），但有两个样本含有高水平的 B19V DNA（1.3×10 和 6.3×10 IU/ml），这两个样本都有可能污染最终的制造商池并导致废弃。封锁期间 B19V 感染的发生率降低（2020 年为 1/3360；2021 年为 0/43200）。对阳性池的单个样本进行基因分析确定了所有 9 个样本中的 B19V 基因型 1。抗 B19V IgG 抗体的血清阳性率为 75%（143/192）。对欧洲 B19V 筛查实践的调查显示存在相当大的差异。两家血液机构告知了 B19V 阳性结果的受感染献血者。
B19V 病毒血症的血清流行率、发病率和病毒载量信息有助于评估血浆检测的替代操作筛查策略。
