Malaria remains a rare but serious complication of transfusion because of the asymptomatic persistence of parasites in some donors. In nonendemic countries, the predominant strategy of deferral or cellular component discard from "risk" donors is effective in minimizing the incidence but is wasteful. In endemic countries where recipients are commonly immune, transfusion strategies focus on chemoprophylaxis for the donor and recipient or ensure that blood collected in highly endemic regions is not transfused to patients from areas of low endemicity. Donors implicated in transfusion-transmitted malaria are predominantly "semi-immune" with very low parasite loads. Their detection by even the most sensitive antigen or polymerase chain reaction (PCR) assays cannot be guaranteed and, in a number of cases, is unlikely because the infectious dose is estimated to be 1 to 10 parasites in a unit of blood. Retrospective analysis of implicated donors has confirmed the presence of high titer antibodies in such individuals. In regions of low immunity, serological assays offer an efficient method to identify such infectious donors. The recent development of enzyme immunoassays (EIAs) with improved sensitivity to Plasmodium falciparum and Plasmodium vivax , the predominant transfusion threats, has heightened the appeal of serological testing. Although universal serological screening in nonendemic regions is not cost-effective, targeted screening of donors identified at risk by travel-based questioning can significantly reduce wastage through reinstatement. Importantly, transfusion safety does not appear to be compromised by this approach as evidenced by the lack of a documented transmission in France between 1983 and September 2002, where such a strategy has been used since 1976. The development of automated protein microarray-based technology has the potential to further enhance antibody/antigen sensitivity; however, its application to donor screening is likely to be some years off. There is also the potential that pathogen inactivation techniques currently under development to address the bacterial contamination of blood components may also be effective against malaria parasites to make malarial testing redundant or at least reduce its cost/benefit ratio. Nonetheless, there are still significant problems to be solved in respect of validating and licensing these systems. Assuming that they are successfully marketed, their high cost may also impact their cost-effectiveness in comparison with targeted malaria testing strategies already in place in some jurisdictions.

中文翻译：

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实验室检测预防输血传播疟疾的现状和潜在作用。

疟疾仍然是一种罕见但严重的输血并发症，因为某些捐助者中无症状的寄生虫持续存在。在非流行国家，从“风险”捐赠者中推迟或丢弃细胞成分的主要策略是有效地将发病率降至最低，但却是浪费。在接受者通常具有免疫力的流行国家，输血策略侧重于对捐赠者和接受者的化学预防，或确保在高流行地区收集的血液不输给低流行地区的患者。与输血传播的疟疾有关的捐赠者主要是“半免疫”的，其寄生虫负荷很低。即使是最敏感的抗原或聚合酶链反应（PCR）分析也无法保证对其进行检测，在许多情况下，这是不可能的，因为传染剂量估计为每单位血液1至10个寄生虫。对牵涉的供体的回顾性分析已证实在此类个体中存在高滴度的抗体。在免疫力低的地区，血清学检测提供了一种有效的方法来鉴定这种感染性供体。酶免疫测定法（EIA）的最新发展是对恶性疟原虫和间日疟原虫（主要输血威胁）具有更高的敏感性，从而提高了血清学检测的吸引力。尽管在非流行地区进行普遍的血清学筛查并不划算，但针对因出行问讯而被识别为有风险的捐献者进行有针对性的筛查可以显着减少因恢复而造成的浪费。重要的，1983年至2002年9月间法国缺乏传播证据，从1976年开始采用这种策略，证明输血安全性并未受到这种方法的损害。基于蛋白质微阵列的自动化技术的发展具有潜力进一步增强抗体/抗原敏感性；但是，将其应用于捐助者筛查可能还需要几年的时间。还有可能的是，目前正在开发的用于解决血液成分细菌污染的病原体灭活技术也可能有效对抗疟原虫，从而使疟疾检测变得多余或至少降低其成本/收益比。但是，在验证和许可这些系统方面仍然存在许多要解决的问题。