Hofmeister Erik K, Lund Melissa, Shearn-Bochsler Valerie, Balakrishnan Christopher N
U.S. Geological Survey, National Wildlife Health Center, Madison, Wisconsin, United States of America.
East Carolina University, Greenville, North Carolina, United States of America.
PLoS One. 2017 Jan 3;12(1):e0167876. doi: 10.1371/journal.pone.0167876. eCollection 2017.
Since the introduction of West Nile virus (WNV) into North America in 1999 a number of passerine bird species have been found to play a role in the amplification of the virus. Arbovirus surveillance, observational studies and experimental studies have implicated passerine birds (songbirds, e.g., crows, American robins, house sparrows, and house finches) as significant reservoirs of WNV in North America, yet we lack a tractable passerine animal model for controlled studies of the virus. The zebra finch (Taeniopygia guttata) serves as a model system across a diversity of fields, and here we develop the zebra finch a songbird model for WNV. Like many natural hosts of WNV, we found that zebra finches developed sufficient viremia to serve as a competent host, yet in general resisted mortality from infection. In the Australian zebra finch (AZF) T. g. castanotis, we detected WNV in the majority of sampled tissues by 4 days post injection (dpi). However, WNV was not detected in tissues of sacrificed birds at 14 dpi, shortly after the development of detectable anti-WNV antibodies in the majority of birds indicating successful viral clearance. We compared susceptibility between the two zebra finch subspecies AZF and Timor zebra finch (TZF) T. g. guttata. Compared to AZF, WNV RNA was detected in a larger proportion of challenged TZF and molecular detection of virus in the serum of TZF was significantly higher than in AZF. Given the observed moderate host competence and disease susceptibility, we suggest that zebra finches are appropriate as models for the study of WNV and although underutilized in this respect, may be ideal models for the study of the many diseases carried and transmitted by songbirds.
自1999年西尼罗河病毒（WNV）传入北美以来，已发现多种雀形目鸟类在该病毒的扩增中发挥作用。虫媒病毒监测、观察性研究和实验性研究表明，雀形目鸟类（鸣禽，如乌鸦、美洲知更鸟、家麻雀和家朱雀）是北美WNV的重要宿主，但我们缺乏用于该病毒对照研究的易处理的雀形目动物模型。斑胸草雀（Taeniopygia guttata）是多个领域的模型系统，在此我们开发了用于WNV研究的斑胸草雀鸣禽模型。与WNV的许多天然宿主一样，我们发现斑胸草雀能产生足够的病毒血症以成为有效宿主，但总体上能抵抗感染导致的死亡。在澳大利亚斑胸草雀（AZF）T. g. castanotis中，注射后4天（dpi）在大多数采样组织中检测到了WNV。然而，在14 dpi时，在处死鸟类的组织中未检测到WNV，此时大多数鸟类已产生可检测到的抗WNV抗体，表明病毒已成功清除。我们比较了两个斑胸草雀亚种AZF和帝汶斑胸草雀（TZF）T. g. guttata之间的易感性。与AZF相比，在受挑战的TZF中检测到WNV RNA的比例更高，且TZF血清中病毒的分子检测显著高于AZF。鉴于观察到的适度宿主能力和疾病易感性，我们认为斑胸草雀适合作为研究WNV的模型，尽管在这方面未得到充分利用，但可能是研究鸣禽携带和传播的许多疾病的理想模型。
