Hepker Monica, Zhang Jianqiang, Anantharam Vellareddy, Kanthasamy Anumantha G, Yuan Jue, Zou Wenquan, Ruden Rachel M
Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA.
Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
Pathogens. 2024 Dec 21;13(12):1133. doi: 10.3390/pathogens13121133.
Disease monitoring informs the opportunities for intervention by natural resource agencies tasked with managing chronic wasting disease (CWD) in wild cervids. However, allocating funds toward testing can reduce those available for education, outreach, and disease reduction. Implementation of more efficient testing strategies can help meet both an expanding need by resource managers and a burgeoning demand from the hunting public in North America. Here, we evaluated the efficacy of pooled testing using the enzyme-linked immunosorbent assay (ELISA), the current screening test used by veterinary diagnostic laboratories in the United States, and real-time quaking-induced conversion (RT-QuIC), an amplification assay that is being evaluated by the U.S. Department of Agriculture but is not yet approved or commercially available. The samples used in this study consisted of medial retropharyngeal lymph nodes (RPLNs) routinely collected by the Iowa Department of Natural Resources during the 2019-2020 surveillance season. The test pools contained tissue from one positive deer diluted in tissue from an increasing number of undetected deer, with each individual contributing an equal tissue volume. ELISA remained positive with pooling thresholds of 1:1, 1:2, 1:4, and 1:9 at a standard volume of tissue homogenate, whereas RT-QuIC remained positive with pooling thresholds of 1:1, 1:2, 1:4, 1:9, 1:19, and 1:49 at a 0.02% tissue dilution. Our results suggest that pooled testing can reduce diagnostic costs multi-fold, and RT-QuIC can be a viable screening test compatible with current field collection standards.
疾病监测为负责管理野生鹿类慢性消耗病（CWD）的自然资源机构提供了干预机会。然而，将资金用于检测会减少可用于教育、宣传和疾病防控的资金。实施更高效的检测策略有助于满足资源管理者不断增长的需求以及北美狩猎公众日益增长的需求。在此，我们评估了采用酶联免疫吸附测定（ELISA，美国兽医诊断实验室目前使用的筛查检测方法）和实时颤抖诱导转化（RT-QuIC，一种正在由美国农业部评估但尚未获批或商业化应用的扩增检测方法）进行混合检测的效果。本研究中使用的样本包括爱荷华州自然资源部在2019 - 2020监测季期间常规采集的咽后内侧淋巴结（RPLNs）。检测池包含来自一只阳性鹿的组织，并在越来越多未检测出的鹿的组织中进行稀释，每个个体贡献相等体积的组织。在标准体积的组织匀浆中，ELISA在1:1、1:2、1:4和1:9的混合阈值下仍呈阳性，而在0.02%的组织稀释度下，RT-QuIC在1:1、1:2、1:4、1:9、1:19和1:49的混合阈值下仍呈阳性。我们的结果表明，混合检测可将诊断成本降低数倍，并且RT-QuIC可以成为一种与当前现场采集标准兼容的可行筛查检测方法。
