School of Biosciences and Veterinary Medicine, University of Camerino, Matelica, Italy.
Zoonoses Public Health. 2018 Nov;65(7):798-804. doi: 10.1111/zph.12501. Epub 2018 Jul 4.
Japanese Encephalitis Virus (JEV) is a flavivirus responsible for an important zoonotic, vector-borne disease included in the OIE list. JEV is endemic in a large area of Asia. In Italy, JEV has been found in dead birds collected in 1997-2000 and in a pool of Culex pipiens mosquitoes collected in 2010. Viral ecology in the inter-epidemic periods is not known. The aim of this study was to investigate JEV in FFPE archival samples of healthy birds collected in 1997-2000 in Tuscany (Italy) in the same area and a few months after collection of birds resulted infected by JEV. Different samples from 37 young birds and 83 adults were available. Immunohistochemistry detected JEV antigen only in bone marrow samples from 12 young healthy birds. Positive cells were morphologically referable to monocyte-macrophages lineage and were positive for anti-CD11b in serial sections. Real-time PCR detected JEV RNA in four of these samples. These results suggest that healthy birds can harbour JEV in bone marrow cells, while no other organs resulted infected. The role of healthy birds in JEV ecology should be better investigated. Surveillance programmes should include sampling of the most appropriate target organs.
日本脑炎病毒（JEV）是一种黄病毒，可导致一种重要的动物源性、媒介传播疾病，被列入世界动物卫生组织（OIE）清单。JEV 在亚洲的大片地区流行。在意大利，JEV 曾在 1997-2000 年采集的死鸟中以及 2010 年采集的库蚊（Culex pipiens）蚊群中被发现。在流行间隔期内，JEV 的病毒生态学尚不清楚。本研究旨在调查 1997-2000 年在意大利托斯卡纳（Tuscany）采集的健康鸟类的 FFPE 存档样本中是否存在 JEV，这些样本来自同一地区，在采集鸟类样本后几个月，这些鸟类被 JEV 感染。共获得 37 只幼鸟和 83 只成年鸟的不同样本。免疫组织化学检测仅在 12 只年轻健康鸟类的骨髓样本中检测到 JEV 抗原。阳性细胞形态上与单核细胞-巨噬细胞谱系相关，在连续切片中对抗 CD11b 呈阳性。实时 PCR 在其中 4 个样本中检测到 JEV RNA。这些结果表明，健康鸟类的骨髓细胞中可能携带 JEV，而其他器官未被感染。健康鸟类在 JEV 生态学中的作用应进一步研究。监测计划应包括对最合适的靶器官进行采样。
