Malcolm Tess R, Klein Melissa J, Petkovic Karolina, Smith Ina, Blasdell Kim R
Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, VIC 3220, Australia.
Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Clayton, VIC 3168, Australia.
Pathogens. 2025 Jan 8;14(1):42. doi: 10.3390/pathogens14010042.
Current arbovirus surveillance strategies in Australia involve mosquito collection, species identification, and virus detection. These processes are labour-intensive, expensive, and time-consuming and can lead to delays in reporting. Mosquito excreta has been proposed as an alternative sample type to whole mosquito collection, with potential to streamline the virus surveillance pipeline. In this study, we investigated the feasibility of excreta as a sample type in the detection of Dengue virus serotype 2 (DENV2). DENV2 could be detected from as little as one DENV2-infected mosquito excreta spot, with virus levels in individual excreta spots varying within and between mosquitoes and depending highly on mosquito viral load. Detectability was improved by pooling up to 20 DENV2-infected mosquitoes and collecting excreta into liquid substrate, followed by virus concentration using magnetic nanoparticles. Virus concentration improves quantification accuracy in comparison to unconcentrated samples and increases the amount of material available for detection, expanding detection capabilities to techniques with higher limits of detection. Mosquito excreta as a sample type, coupled with magnetic virus concentration, expands the current detection toolbox for DENV2 and has the potential to improve arbovirus surveillance strategies in Australia.
澳大利亚当前的虫媒病毒监测策略包括蚊子采集、物种鉴定和病毒检测。这些过程劳动强度大、成本高且耗时，可能导致报告延迟。蚊子排泄物已被提议作为全蚊采集的替代样本类型，有望简化病毒监测流程。在本研究中，我们调查了将排泄物作为样本类型用于检测登革热病毒2型（DENV2）的可行性。从仅一个感染DENV2的蚊子排泄物斑点中就能检测到DENV2，单个排泄物斑点中的病毒水平在蚊子内部和蚊子之间存在差异，并且高度依赖于蚊子的病毒载量。通过汇集多达20只感染DENV2的蚊子并将排泄物收集到液体基质中，然后使用磁性纳米颗粒进行病毒浓缩，可提高可检测性。与未浓缩的样本相比，病毒浓缩提高了定量准确性，并增加了可用于检测的材料量，将检测能力扩展到具有更高检测限的技术。蚊子排泄物作为一种样本类型，再加上磁性病毒浓缩，扩展了当前用于DENV2的检测工具箱，并有可能改进澳大利亚的虫媒病毒监测策略。
