RNA viruses of pandemic potential: Viral Infectivity

RNA病毒是当前和未来主要流行病的原因，几乎没有抗病毒药物，而且有可能 给全球医疗体系带来严重压力。过去一年，严重急性呼吸系统综合症 冠状病毒-2(SARS-CoV-2)是一种正链RNA病毒，是新冠肺炎的病原体，已 在全球范围内造成了严重的破坏。虽然最近的一次流感大流行(2009年)有 死亡率相对较低，出现一种死亡率较高的新型流感病毒株将 全球医疗体系承受着巨大的压力，而且仍然是一个持续的威胁。在.的情况下 SARS-CoV-2(可能是未来的任何冠状病毒或流感大流行)，对病毒的无与伦比的需求 诊断性检测导致全球许多所需试剂短缺。核糖核酸的提取 特指的是一个瓶颈，不仅是因为所需试剂的短缺，还因为 提取过程的成本、执行该过程所需的劳动力和时间。虽然最近的紧急使用 美国食品和药物管理局已批准将其用于商业 免提取诊断测试，这是专有系统；与开放源码的 需要世界卫生组织建立的RT-qPCR方法。这项研究的目标是调查 与SARS-CoV-2和流感的病毒传染性相关和/或影响，使用临床样本和 传统的病毒学技术，以检查是什么使特定的病毒或特定的患者具有传染性。 先前资助的旨在开发简化SARS-CoV-2的试验项目的扩展 在诊断性测试方面，我们将扩大我们的检查范围，将临床流感样本包括在内。此外，我们还将 探讨包括sgRNA、负链RNA和SARS-CoV-2 RNA载量在内的多个因素 综合考虑可能能够预测传染性病毒的存在，并有可能区分 那些仅仅是聚合酶链式反应阳性的人，而不是那些真正构成病毒传播风险的人。 由于这项工作将产生一组SARS-CoV-2和流感临床分离株， 对于感染性，我们还将调查各种因素，包括RNA包装、颗粒与PFU的比例、 温度稳定性、颗粒形态和特定的基因突变，所有这些都可能影响病毒 分子水平上的传染性。

RNA viruses are the cause of major current and future pandemics, with few antivirals and the potential to severely strain global healthcare systems. In the past year, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a positive strand RNA virus that is the causative agent of COVID-19, has caused acute disruption on a global scale. While the most recent influenza pandemic (2009) had a relatively low mortality rate, the emergence of a novel influenza strain with higher mortality would place the global healthcare system under immense pressure, and remains a constant threat. In the case of SARS-CoV-2 (and likely any future coronavirus or influenza pandemic), an unparalleled demand for viral diagnostic testing resulted in global shortages of many of the required reagents. RNA extraction in particular represents a choke point, not only due to shortages of the required reagents, but also due to the cost of the extraction process, the labor and time required to perform it. While recent Emergency Use Authorizations have been approved by the US Food and Drug Administration for commercial extraction-free diagnostic tests, these are proprietary systems; protocols that work with the open-source RT-qPCR assay developed by the WHO are needed. The goal of this study is to investigate factors that correlate with and/or influence viral infectivity of SARS-CoV-2 and influenza, using clinical samples and classical virology techniques to examine what makes the particular virus, or a particular patient, infectious. An extension of a previously funded pilot project aimed at developing a streamlined SARS-CoV-2 diagnostic test, we will expand our examination to include clinical influenza samples. Additionally, we will probe a number of factors including sgRNA, negative strand RNA and SARS-CoV-2 RNA loads that considered together may be able predict the presence of infectious virus, and potentially differentiate those individuals who are simply PCR-positive from those who truly pose a risk of viral transmission. Since this work will generate a panel of clinical isolates for both SARS-CoV-2 and influenza with a range of infectivities, we will also investigate a variety of factors including RNA packaging, particle to PFU ratio, temperature stability, particle morphology and specific genetic mutations, all of which may affect viral infectivity at the molecular level.