Department of Industrial and Manufacturing Engineering, Penn State University, University Park, PA, 16803, USA.
Department of Industrial and Manufacturing Engineering, Penn State University, University Park, PA, 16803, USA.
Comput Biol Med. 2021 Jul;134:104518. doi: 10.1016/j.compbiomed.2021.104518. Epub 2021 May 29.
Many schools and universities have seen a significant increase in the spread of COVID-19. As such, a number of non-pharmaceutical interventions have been proposed including distancing requirements, surveillance testing, and updating ventilation systems. Unfortunately, there is limited guidance for which policy or set of policies are most effective for a specific school system. We develop a novel approach to model the spread of SARS-CoV-2 quanta in a closed classroom environment that extends traditional transmission models that assume uniform mixing through air recirculation by including the local spread of quanta from a contagious source. In addition, the behavior of students with respect to guideline compliance was modeled through an agent-based simulation. Estimated infection rates were on average lower using traditional transmission models compared to our approach. Further, we found that although ventilation changes were effective at reducing mean transmission risk, it had much less impact than distancing practices. Duration of the class was an important factor in determining the transmission risk. For the same total number of semester hours for a class, delivering lectures more frequently for shorter durations was preferable to less frequently with longer durations. Finally, as expected, as the contact tracing level increased, more infectious students were identified and removed from the environment and the spread slowed, though there were diminishing returns. These findings can help provide guidance as to which school-based policies would be most effective at reducing risk and can be used in a cost/comparative effectiveness estimation study given local costs and constraints.
许多学校和大学都看到 COVID-19 的传播显著增加。因此，提出了许多非药物干预措施，包括距离要求、监测测试和更新通风系统。不幸的是，对于哪种政策或政策组合对特定的学校系统最有效，指导有限。我们开发了一种新颖的方法来模拟封闭教室环境中 SARS-CoV-2 量子的传播，该方法扩展了传统的传输模型，这些模型通过包括从传染性源传播的量子的局部传播，假设通过空气再循环实现均匀混合。此外，通过基于代理的模拟对学生遵守指导方针的行为进行了建模。与我们的方法相比，传统传输模型估计的感染率平均较低。此外，我们发现，尽管通风变化可有效降低平均传播风险，但与距离实践相比，其影响要小得多。课程的持续时间是确定传播风险的一个重要因素。对于同一门课的总课时数，如果更频繁地进行较短的课程，而不是不那么频繁地进行较长的课程，那么传播风险就更小。最后，正如预期的那样，随着接触者追踪水平的提高，更多的传染性学生被识别并从环境中移除，传播速度减缓，尽管回报递减。这些发现可以帮助提供指导，说明哪种基于学校的政策可以最有效地降低风险，并可用于基于当地成本和限制的成本/比较效果评估研究。
