Japanese Red Cross Hokkaido Block Blood Center, Sapporo, Japan.
Central Blood Institute, Blood Service Headquarters, Japanese Red Cross Society, Tokyo, Japan.
Transfusion. 2021 Dec;61(12):3390-3401. doi: 10.1111/trf.16700. Epub 2021 Oct 10.
After experiencing several cases of transfusion-transmitted hepatitis E (TT-HE) in Hokkaido, Northern Japan, hepatitis E virus (HEV) screening in blood donors, using a nucleic acid amplification test (NAT), was introduced in 2005.
The frequency of HEV RNA-positive donations (2005-2019) was investigated, and the HEV RNA-positive specimens were phylogenetically analyzed. In August 2014, the 20-pooled NAT (20P-NAT) was replaced with an individual-NAT (ID-NAT) system.
Until 2019, the frequency of HEV RNA-positive donors was 0.011% (289/2,638,685) with 20P-NAT and 0.043% (597/1,379,750) with ID-NAT, and no TT-HE cases were observed in Hokkaido. The prevalence among male, but not female donors, increased significantly between 2015 and 2019. Eighty-nine percent of HEV isolates from donors were genotype 3 and the remainder were genotype 4, and many clusters existed in each genotype. ALT levels at the time of donation were significantly higher in donors with genotype 4. Four subgenotypes, namely 3a (37%), 3b (41%), 3e (6%), and 4c (10%), comprised 94% of the total. During this period, the most identified subgenotype, 3a, transitioned to 3b. Majority of the HEV strains within the same clusters were detected in the same geographical region around the same period. Many of the human HEV isolates were shown to coexist closely with animal HEV isolates phylogenetically.
In Hokkaido, multiple divergent HEV strains have been circulating, and small outbreaks of hepatitis E have occurred in the last 15 years. The results suggested that HEV NAT can contribute significantly in ensuring safety during blood transfusions.
在日本北部北海道经历了几例输血传播性戊型肝炎（TT-HE）后，2005 年开始在献血者中使用核酸扩增检测（NAT）筛查戊型肝炎病毒（HEV）。
调查了 2005-2019 年期间 HEV RNA 阳性献血者的频率，并对 HEV RNA 阳性标本进行了系统进化分析。2014 年 8 月，20 份混合 NAT（20P-NAT）被个体 NAT（ID-NAT）系统取代。
截至 2019 年，采用 20P-NAT 时，HEV RNA 阳性献血者的频率为 0.011%（289/2,638,685），采用 ID-NAT 时为 0.043%（597/1,379,750），北海道未观察到 TT-HE 病例。男性献血者的阳性率显著高于女性，且在 2015 年至 2019 年间呈上升趋势。89%的供体分离株为基因型 3，其余为基因型 4，每个基因型都存在许多聚类。捐赠时 ALT 水平在基因型 4 供体中显著较高。4 个子基因型，即 3a（37%）、3b（41%）、3e（6%）和 4c（10%），占总数的 94%。在此期间，最常见的亚基因型 3a 转变为 3b。同一时期同一地理区域内同一聚类中检测到的大多数 HEV 株系均密切相关。许多人类 HEV 分离株与动物 HEV 分离株在系统进化上密切共存。
在北海道，多种不同的 HEV 株系一直在传播，在过去 15 年中发生了多次小型戊型肝炎暴发。结果表明，HEV NAT 可显著有助于确保输血安全。
