Linking SARS-CoV-2 Aerosol Viability and Environmental Factors in Healthcare Settings

项目摘要/摘要 新冠肺炎和流感等呼吸道感染患者的病毒雾化是主要的 医疗保健方面的担忧，因为这些病毒可能会使医护人员(HCP)和患者面临 感染。这项研究的基本原理是，虽然流行病学研究已经确定了一些医疗保健 被认为对六氯苯酚有很高风险的活动，以及这些活动被认为会产生气雾剂， 关于气溶胶中传染性病毒的浓度和大小分布的信息有限。因此，它 仍然很难识别产生气雾剂的医疗活动，也很难区分哪些活动会造成高 对HCP和患者的风险。这项研究的长期目标是防止病毒疾病的传播。 通过呼吸气雾剂。提出了三个目标。目标1是开发和评估一种尺寸选择 方法检测气雾剂中的活病毒。商业上可用的尺寸选择进水口，符合健康要求 将对抽样惯例进行评估，以便与创新的仪器--活病毒气溶胶采样器一起使用 (Vivas，Aerosol Devices，Inc.)，附参考气雾剂和噬菌体MS2。目标2是描述 医疗保健活动产生的活病毒气溶胶的浓度和大小分布。一个或多个 来自AIM 1的进气口将与传统的气溶胶采样设备一起安装，以测量选定的尺寸 活病毒，选定大小的病毒遗传物质，以及气溶胶数量和大小分布 流感或新冠肺炎患者。将研究六项保健活动，每项活动都有6-9项针对COVID的观察- 19例患者和6-9例流感患者的观察。这些活动将根据初步结果进行选择 气溶胶15项活动的特征。目标2的主要假设是，呼吸系统的变化 气溶胶在医疗保健活动中比在医疗保健活动中更大，并且在 病毒，这意味着某些活动比其他活动产生更多或不同的气溶胶。第二个 目标2的假设是，病毒基因拷贝数与呼吸气溶胶中活病毒的比率不同。 在医疗保健活动内部或之间有所不同，如果是真的，这意味着可行的病毒浓度可能是 从聚合酶链式反应结果可靠地推断。目标3是将气雾剂特性与患者、程序和环境联系起来 特点。目标3的主要假设是呼吸气溶胶特征的变化 由环境、患者和医疗保健活动特征解释的相对于内部变化较小 以及医疗保健活动，这反映了环境和患者的有限差异 由于这项研究在医疗机构和 住院病人。通过这项研究产生的知识将极大地提高我们的理解 呼吸性气溶胶中的病毒所构成的风险。感染预防专家将能够利用这一知识 教育HCP，并选择允许HCP安全有效地履行其工作的控制策略。这个 这项研究的结果将是气溶胶产生活动的循证感染预防做法。

PROJECT SUMMARY/ABSTRACT Aerosolization of viruses from patients with respiratory infections, such as COVID-19 and influenza, is a major concern in healthcare because these viruses can put healthcare personnel (HCP) and patients at risk of infection. The rationale for this study is that while epidemiology studies have identified some healthcare activities as posing a high risk to HCP and these activities are thought to generate aerosols, there exists very limited information about the concentration and size distribution of infectious virus in the aerosol. As a result, it remains difficult to identify aerosol-generating healthcare activities and to distinguish those that pose a high risk to HCP and patients. The long-term goal of this research is to prevent the transmission of viral diseases through respiratory aerosol. Three aims are proposed. Aim 1 is to develop and evaluate a size-selective method to assess viable virus in aerosol. Commercially available size-selective inlets meeting health-based sampling conventions will be evaluated for use with an innovative instrument, the Viable Virus Aerosol Sampler (VIVAS, Aerosol Devices, Inc.), with reference aerosols and bacteriophage MS2. Aim 2 is to characterize the concentration and size distribution of viable virus aerosol generated from healthcare activities.One or more inlet from Aim 1 will be deployed alongside conventional aerosol sampling equipment to measuresize-selected viable virus, size-selected virus genetic material, and aerosol number and size distribution in rooms with influenza or COVID-19 patients. Six healthcare activities will be studied, each with 6-9 observationsfor COVID- 19 patients and 6-9 observations for influenza patients. These activities will be selected based on preliminary aerosol characterization of 15 activities. The primary hypothesis of Aim 2 is that the variance in respiratory aerosol is greater among healthcare activities than within healthcare activities, and does not vary between viruses, which implies that some activities generate more or different aerosol than others. The secondary hypothesis of Aim 2 is that therethe ratio of virus gene copies to viable virus in respiratory aerosol does not vary within or among healthcare activities, which, if true, means that the viable virus concentration can be reliably inferred from PCR results. Aim 3 is to link aerosol properties to patient, procedure, and environmental characteristics. The primary hypothesis of Aim 3 is that the variance in respiratory aerosol characteristics explained by environmental, patient, and healthcare activity characteristics is small relative to variation within and among healthcare activities, which reflects that limited variation in environmental and patient characteristics are expected owing to the performance of this research in a healthcare facility and among hospitalized patients. The knowledge generated through this research will greatly enhance our understanding ofthe risks posed by viruses in respiratory aerosol. Infection preventionists will be able to use this knowledge to educate HCP, and to select control strategies that permit HCP to perform their jobs safely and efficiently. The outcome of this research will be evidence-based infection prevention practices for aerosol-generating activities.