In the last decade, the number of emerging Flaviviruses described worldwide has increased considerably. Among them Zika virus (ZIKV) and Usutu virus (USUV) are African mosquito-borne viruses that recently emerged. Recently, ZIKV has been intensely studied due to major outbreaks associated with neonatal death and birth defects, as well as neurological symptoms. USUV pathogenesis remains largely unexplored, despite significant human and veterinary associated disorders. Circulation of USUV in Africa was documented more than 50 years ago, and it emerged in Europe two decades ago, causing massive bird mortality. More recently, USUV has been described to be associated with neurological disorders in humans such as encephalitis and meningoencephalitis, highlighting USUV as a potential health threat. The aim of this study was to evaluate the ability of USUV to infect neuronal cells. Our results indicate that USUV efficiently infects neurons, astrocytes, microglia and IPSc-derived human neuronal stem cells. When compared to ZIKV, USUV led to a higher infection rate, viral production, as well as stronger cell death and anti-viral response. Our results highlight the need to better characterize the physiopathology related to USUV infection in order to anticipate the potential threat of USUV emergence.

在过去的十年中，全世界描述的新兴黄病毒的数量已大大增加。其中寨卡病毒（ZIKV）和乌苏图病毒（USUV）是最近出现的非洲蚊媒病毒。最近，由于与新生儿死亡和出生缺陷以及神经系统症状有关的重大暴发，对ZIKV进行了深入研究。尽管存在重大的人类和兽医相关疾病，USUV的发病机理仍未得到充分探索。USUV在非洲的传播已有50多年的历史了，在20年前的欧洲就已流行，造成大量鸟类死亡。最近，USUV已被描述与人类的神经系统疾病有关，例如脑炎和脑膜脑炎，这突出表明USUV是一种潜在的健康威胁。这项研究的目的是评估USUV感染神经元细胞的能力。我们的结果表明，USUV有效感染神经元，星形胶质细胞，小胶质细胞和IPSc衍生的人神经元干细胞。与ZIKV相比，USUV导致更高的感染率，病毒产生以及更强的细胞死亡和抗病毒反应。我们的结果表明，有必要更好地表征与USUV感染有关的生理病理，以预测USUV出现的潜在威胁。