Division of Injury Prevention, National Center for Injury Prevention and Control (Drs Miller and Rice), Division of Preparedness and Emerging Infections, National Center for Emerging & Zoonotic Infectious Diseases (Drs Greening Jr and Meltzer), Policy Research, Analysis, and Development Office, Office of the Associate Director for Policy and Strategy (Dr Arifkhanova), and Division for Heart Disease and Stroke Prevention, National Center for Chronic Disease Prevention & Health Promotion (Dr Coronado), Centers for Disease Control and Prevention, Atlanta, Georgia.
J Public Health Manag Pract. 2022;28(1):25-35. doi: 10.1097/PHH.0000000000001373.
Schools are an integral part of the community; however, congregate settings facilitate transmission of SARS-CoV-2, presenting a challenge to school administrators to provide a safe, in-school environment for students and staff.
We adapted the Centers for Disease Control and Prevention's COVIDTracer Advanced tool to model the transmission of SARS-CoV-2 in a school of 596 individuals. We estimate possible reductions in cases and hospitalizations among this population using a scenario-based analysis that accounts for (a) the risk of importation of infection from the community; (b) adherence to key Centers for Disease Control and Prevention-recommended mitigation strategies: mask wearing, cleaning and disinfection, hand hygiene, and social distancing; and (c) the effectiveness of contact tracing interventions at limiting onward transmission.
Low impact and effectiveness of mitigation strategies (net effectiveness: 27%) result in approximately 40% of exposed staff and students becoming COVID-19 cases. When the net effectiveness of mitigation strategies was 69% or greater, in-school transmission was mostly prevented, yet importation of cases from the surrounding community could result in nearly 20% of the school's population becoming infected within 180 days. The combined effects of mitigation strategies and contact tracing were able to prevent most onward transmission. Hospitalizations were low among children and adults (<0.5% of the school population) across all scenarios examined.
Based on our model, layering mitigation strategies and contact tracing can limit the number of cases that may occur from transmission in schools. Schools in communities with substantial levels of community spread will need to be more vigilant to ensure adherence of mitigation strategies to minimize transmission. Our results show that for school administrators, teachers, and parents to provide the safest environment, it is important to utilize multiple mitigation strategies and contract tracing that reduce SARS CoV-2 transmission by at least 69%. This will require training, reinforcement, and vigilance to ensure that the highest level of adherence is maintained over the entire school term.
学校是社区的一个组成部分；然而，聚集性场所有利于 SARS-CoV-2 的传播，这给学校管理人员带来了挑战，他们需要为学生和教职员工提供一个安全的校内环境。
我们改编了疾病控制与预防中心的 COVIDTracer 高级工具，以模拟一所拥有 596 名个体的学校中 SARS-CoV-2 的传播。我们通过基于情景的分析来估计该人群中病例和住院人数的可能减少，该分析考虑了以下因素：(a) 从社区传入感染的风险；(b) 遵守疾病控制与预防中心建议的关键缓解策略：戴口罩、清洁和消毒、手部卫生和保持社交距离；以及 (c) 接触者追踪干预措施限制传播的有效性。
缓解策略的影响和效果较低（净效果：27%）导致大约 40%的暴露员工和学生成为 COVID-19 病例。当缓解策略的净效果达到 69%或更高时，校内传播大多得到预防，但来自周边社区的病例传入可能导致学校人口的近 20%在 180 天内感染。缓解策略和接触者追踪的综合效果能够阻止大多数传播。在所有检查的情景中，儿童和成人的住院率都较低（不到学校人口的 0.5%）。
根据我们的模型，分层缓解策略和接触者追踪可以限制学校传播引起的病例数量。在社区传播水平较高的社区中，学校需要更加警惕，以确保遵守缓解策略，将传播风险降至最低。我们的结果表明，为了让学校管理人员、教师和家长提供最安全的环境，重要的是要利用多种缓解策略和接触者追踪，将 SARS CoV-2 的传播减少至少 69%。这将需要培训、强化和警惕，以确保在整个学校期间保持最高水平的遵守。
