Verily Life Sciences, South San Francisco, CA, United States of America.
Google Research, Mountain View, CA, United States of America.
PLoS One. 2021 Aug 12;16(8):e0254798. doi: 10.1371/journal.pone.0254798. eCollection 2021.
As society has moved past the initial phase of the COVID-19 crisis that relied on broad-spectrum shutdowns as a stopgap method, industries and institutions have faced the daunting question of how to return to a stabilized state of activities and more fully reopen the economy. A core problem is how to return people to their workplaces and educational institutions in a manner that is safe, ethical, grounded in science, and takes into account the unique factors and needs of each organization and community. In this paper, we introduce an epidemiological model (the "Community-Workplace" model) that accounts for SARS-CoV-2 transmission within the workplace, within the surrounding community, and between them. We use this multi-group deterministic compartmental model to consider various testing strategies that, together with symptom screening, exposure tracking, and nonpharmaceutical interventions (NPI) such as mask wearing and physical distancing, aim to reduce disease spread in the workplace. Our framework is designed to be adaptable to a variety of specific workplace environments to support planning efforts as reopenings continue. Using this model, we consider a number of case studies, including an office workplace, a factory floor, and a university campus. Analysis of these cases illustrates that continuous testing can help a workplace avoid an outbreak by reducing undetected infectiousness even in high-contact environments. We find that a university setting, where individuals spend more time on campus and have a higher contact load, requires more testing to remain safe, compared to a factory or office setting. Under the modeling assumptions, we find that maintaining a prevalence below 3% can be achieved in an office setting by testing its workforce every two weeks, whereas achieving this same goal for a university could require as much as fourfold more testing (i.e., testing the entire campus population twice a week). Our model also simulates the dynamics of reduced spread that result from the introduction of mitigation measures when test results reveal the early stages of a workplace outbreak. We use this to show that a vigilant university that has the ability to quickly react to outbreaks can be justified in implementing testing at the same rate as a lower-risk office workplace. Finally, we quantify the devastating impact that an outbreak in a small-town college could have on the surrounding community, which supports the notion that communities can be better protected by supporting their local places of business in preventing onsite spread of disease.
随着社会逐渐走出依赖广泛封锁作为权宜之计的 COVID-19 危机初始阶段,各行业和机构面临着如何恢复稳定活动状态并更全面地重新开放经济的艰巨问题。一个核心问题是如何以安全、合乎道德、基于科学并考虑每个组织和社区独特因素和需求的方式让人们返回工作场所和教育机构。在本文中,我们引入了一个考虑 SARS-CoV-2 在工作场所内、工作场所周围社区内以及两者之间传播的流行病学模型(“社区-工作场所”模型)。我们使用这个多群组确定性房室模型来考虑各种测试策略,这些策略与症状筛查、接触追踪以及非药物干预措施(如佩戴口罩和保持身体距离)一起,旨在减少工作场所的疾病传播。我们的框架旨在适应各种特定的工作场所环境,以支持持续的重新开放计划。使用这个模型,我们考虑了一些案例研究,包括一个办公室工作场所、一个工厂车间和一个大学校园。这些案例的分析表明,即使在高接触环境中,持续测试也可以通过减少未被发现的传染性来帮助工作场所避免疫情爆发。我们发现,与工厂或办公室环境相比,个人在校园中花费更多时间且接触负荷更高的大学校园环境需要更多的测试才能保持安全。根据建模假设,我们发现通过每两周测试其员工,在办公室环境中可以将患病率保持在 3%以下,而要达到同一目标对于大学环境则可能需要增加四倍的测试(即,每周对整个校园人口进行两次测试)。我们的模型还模拟了在工作场所爆发早期阶段通过引入缓解措施而导致传播减少的动态。我们使用这一点表明,一个具有快速应对疫情能力的警惕大学可以证明在以与低风险办公室工作场所相同的速度进行测试是合理的。最后,我们量化了一个小镇大学疫情爆发对周围社区的毁灭性影响,这支持了这样一种观点,即通过支持当地企业来防止疾病在现场传播,可以更好地保护社区。