South African National Blood Service, Roodepoort, South Africa.
Vitalant Research Institute, San Francisco, CA, USA.
Vox Sang. 2019 Jul;114(5):451-458. doi: 10.1111/vox.12778. Epub 2019 Apr 4.
Donated blood is not currently screened for human T-cell lymphotropic virus (HTLV) in South Africa. Several small studies have detected HTLV-1 in South Africa, but prevalence by geographic region or population group is unavailable.
We performed a large seroprevalence study of South African blood donors during 3 months in 2013. All geographic regions except the Western Cape were included, and Black and Coloured (local term for mixed race) donors were oversampled. Identity-unlinked plasma samples were screened with the Abbott Prism HTLV-1/2 assay, and repeatedly reactive samples were tested by the Inno-LIA HTLV-1/2 Score confirmatory assay. Odds ratios were calculated with multivariable logistic regression.
Of 46 752 donors tested, 133 (0·28%) were initially reactive, 111 (0·24%) repeatedly reactive and 57 (0·12%) confirmed positive for HTLV-1; none were HTLV-2 positive. Prevalence was 0·062% weighted to annual blood donations but highly concentrated in the Black population group (OR = 20·24 CI: 2·77-147·88); higher in females than males (OR = 1·81 CI: 1·06-3·08); and in donors aged >50 years compared to ages 16-19 (OR = 6·4 CI: 2·95-13·86). After controlling for age, sex and population group, there was no difference in prevalence between new and repeat blood donors or among geographic regions within South Africa.
We conclude that HTLV-1 infection is widespread among the Black population of South Africa and its epidemiology is similar to other endemic areas. Because South Africa is increasing its recruitment of Black blood donors, the implications for blood screening require further consideration.
目前南非的捐血并未筛检人类 T 细胞淋巴球病毒（human T-cell lymphotropic virus，HTLV）。虽然有几项小型研究在南非发现 HTLV-1，但关于其流行率的地理区域或族群资料尚未可知。
我们于 2013 年 3 个月期间，对南非捐血者进行了一项大型血清流行率研究。除了西开普省（Western Cape）以外，所有地理区域都包括在内，且对黑人和混血儿（当地对混合种族的称呼）捐血者进行了超额采样。使用 Abbott Prism HTLV-1/2 检测进行非关联身份血浆样本筛查，对重复出现反应的样本则用 Inno-LIA HTLV-1/2 Score 确证检测进行检测。采用多变量逻辑回归计算比值比（odds ratio）。
在 46752 名受检捐血者中，有 133 名（0·28%）初始反应，111 名（0·24%）重复反应，57 名（0·12%）经确证对 HTLV-1 呈阳性；无一例对 HTLV-2 呈阳性。经加权至年度捐血量后，流行率为 0·062%，但高度集中于黑人族群（比值比[OR] 20·24，95%置信区间[CI]：2·77-147·88）；女性高于男性（OR 1·81，95%CI：1·06-3·08）；与 16-19 岁年龄组相比，年龄>50 岁者更高（OR 6·4，95%CI：2·95-13·86）。控制年龄、性别和族群后，新捐血者与重复捐血者、南非各地理区域之间的流行率无差异。
我们的结论是，HTLV-1 感染在南非黑人族群中广泛流行，其流行病学与其他流行地区相似。由于南非正在增加黑人捐血者的招募，因此对捐血筛查的影响需要进一步考虑。
