Surveillance of Usutu virus is crucial to prevent future outbreaks both in Europe and in other countries currently naïve to the infection, such as the Americas. This goal remains difficult to achieve, notably because of the lack of large-scale cohort studies and the absence of commercially available diagnostic reagents for USUV. This work started with the first identification of USUV in a blood donor in the Friuli Venezia Giulia (FVG) Region in Northern-Eastern Italy, which is endemic for West Nile virus. Considering that only one IgG ELISA is commercially available, but none for IgM, a novel NS1 antigen based IgG/M ELISA has been developed. This assay tested successfully for the detection of Usutu virus in blood donors with the identification of a second case of transmission and high levels of exposure. Furthermore, two pan-flavivirus antiviral drugs, that we previously characterized to be inhibitors of other flavivirus infectivity, were successfully tested for inhibition of Usutu virus with inhibitory concentrations in the low micromolar range. To conclude, this work identifies North-Eastern Italy as endemic for Usutu virus with implications for the screening of transfusion blood. A novel NS1-based ELISA test has been implemented for the detection of IgM/G that will be of importance as a tool for the diagnosis and surveillance of Usutu virus infection. Finally, Usutu virus is shown to be sensitive to a class of promising pan-flavivirus drugs.

中文翻译：

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在意大利的弗留利·威尼斯·朱利亚地区的献血者中首次分离后，对Usutu病毒的全面反应：基于NS1的重组血清学的发展和对抗病毒药物的敏感性。

监视Usutu病毒对于防止欧洲和目前尚不感染的其他国家（如美洲）未来的爆发至关重要。该目标仍然难以实现，特别是因为缺乏大规模的队列研究，也没有针对USUV的市售诊断试剂。这项工作始于在意大利东北部的弗留利·威尼斯·朱利亚（FVG）地区的一个献血者中首次发现USUV，这是西尼罗河病毒的地方病。考虑到只有一种IgG ELISA是可商购的，但对于IgM却没有，因此已开发出一种基于NS1抗原的新型IgG / M ELISA。通过鉴定第二种传播途径和高暴露水平，该测定法成功测试了在献血者中检测Usutu病毒。此外，我们已成功测试了两种泛黄病毒抗病毒药物（我们以前将其表征为其他黄病毒感染性的抑制剂）以低微摩尔范围的抑制浓度抑制了乌索都病毒。总而言之，这项工作确定了意大利东北部地区是Usutu病毒的地方病，对筛查输血具有重要意义。已经实施了一种基于NS1的新型ELISA试验，用于检测IgM / G，这对于诊断和监测Usutu病毒感染具有重要意义。最后，已证明Usutu病毒对一类有前景的泛黄病毒药物敏感。这项工作确定了意大利东北部地区是Usutu病毒的地方病，对筛查输血具有重要意义。已经实施了一种基于NS1的新型ELISA试验，用于检测IgM / G，这对于诊断和监测Usutu病毒感染具有重要意义。最后，已证明Usutu病毒对一类有前景的泛黄病毒药物敏感。这项工作确定了意大利东北部地区是Usutu病毒的地方病，对筛查输血具有重要意义。已经实施了一种基于NS1的新型ELISA试验，用于检测IgM / G，这对于诊断和监测Usutu病毒感染具有重要意义。最后，已证明Usutu病毒对一类有前景的泛黄病毒药物敏感。