Olufemi Olaolu T, Barba Marta, Daly Janet M
One Virology-Wolfson Centre for Global Virus Research, School of Veterinary Medicine and Science, University of Nottingham, Loughborough LE12 5RD, UK.
Department of Veterinary Public Health and Preventive Medicine, Faculty of Veterinary Medicine, University of Jos, Jos 930003, Nigeria.
Pathogens. 2021 Jul 15;10(7):899. doi: 10.3390/pathogens10070899.
West Nile virus (WNV) is an emerging and re-emerging zoonotic flavivirus first identified in and endemic to Africa. The virus is transmitted between birds by biting mosquitoes, with equids and humans being incidental hosts. The majority of infected incidental hosts display no or only mild clinical signs, but a fraction develop encephalitis. The aim of this scoping review was to identify and evaluate primary research on the presence of antibodies to WNV among African equids. Three bibliographic databases and the grey literature were searched. Of 283 articles identified, only 16 satisfied all the inclusion criteria. Data were collated on study design and outcomes. The overall seroprevalence reported ranged from 17.4 to 90.3%, with 1998 (35%) of the 5746 horses, donkeys and mules having screened positive for WNV antibodies. Several articles determined that seroprevalence increased significantly with age. Due to co-circulation of other flaviviruses in Africa, in the majority of studies that screened samples by ELISA, positive results were confirmed using a more specific neutralization test. However, only eight studies tested against other flaviviruses, including Potiskum, Uganda S, Wesselsbron and yellow fever virus in one, Japanese encephalitis and Usutu virus (USUV) in one, tick-borne encephalitis and USUV in one and USUV only in three. Equids are regarded as useful sentinel animals for WNV, but variation in study design poses challenges when trying to determine risk factors for, and trends in, WNV seroprevalence.
西尼罗河病毒（WNV）是一种新出现且再度出现的人畜共患黄病毒，最初在非洲被发现并呈地方性流行。该病毒通过叮咬蚊子在鸟类之间传播，马和人类是偶然宿主。大多数被感染的偶然宿主没有临床症状或仅有轻微症状，但有一部分会发展为脑炎。本综述的目的是识别和评估关于非洲马属动物中WNV抗体存在情况的初步研究。检索了三个文献数据库和灰色文献。在识别出的283篇文章中，只有16篇符合所有纳入标准。对研究设计和结果进行了整理。报告的总体血清阳性率在17.4%至90.3%之间，在5746匹马、驴和骡子中，有1998匹（35%）的WNV抗体检测呈阳性。几篇文章确定血清阳性率随年龄显著增加。由于非洲其他黄病毒的共同传播，在大多数通过酶联免疫吸附测定（ELISA）筛查样本的研究中，使用更特异的中和试验来确认阳性结果。然而，只有八项研究针对其他黄病毒进行了检测，其中一项检测了波蒂斯科姆病毒、乌干达S病毒、韦塞尔布伦病毒和黄热病病毒，一项检测了日本脑炎病毒和乌苏图病毒（USUV），一项检测了蜱传脑炎病毒和USUV，三项仅检测了USUV。马属动物被视为WNV的有用哨兵动物，但研究设计的差异在试图确定WNV血清阳性率的风险因素和趋势时带来了挑战。
