Department of Pediatrics, Aspirus Doctors Clinic, Wisconsin Rapids, Wisconsin,
Medical College of Wisconsin-Central Wisconsin, Wausau, Wisconsin.
WMJ. 2022 Apr;121(1):13-17.
K-12 schools have shown minimal spread of COVID-19 when mitigation measures are employed. This study sought to determine baseline asymptomatic COVID-19 rates in secondary schools as students returned to full-time in-person learning with universal masking in place and to evaluate the logistical obstacles of implementing surveillance testing.
An observational cohort study lasting 11 weeks during spring 2021 included 2,288 students and staff in Wood County, Wisconsin. SARS-CoV-2 nasal polymerase chain reaction testing was done on consenting students and staff to determine baseline disease burden. Teacher surveys collected data on student masking compliance and classroom distancing. Information about percent positivity, secondary transmission, quarantine and distancing policies, screening participation, costs, and volunteer hour requirements were obtained. Modified quarantine for fully masked in-classroom exposures was evaluated.
Percent positivity averaged 3.0% (0%-16.2% weekly) among students and 1.72% (0%-6.9% weekly) among staff. Two cases of secondary transmission were suspected out of 163 individuals quarantined. An average of 15.6% of the school population consented to participate each week. Minimum classroom distance between students ranged from 2.7 to 5.5 feet. Student masking compliance was greater than 87%. The cost of the program was $106,400 and required approximately 300 volunteer hours. The modified quarantine policy, where students were allowed to continue to attend in-person school after exposure to a case of COVID-19 if the infected and exposed parties were masking, did not result in additional transmission.
In the setting of relatively high student masking compliance and limited distance between students, weekly secondary school screening of students and staff in an area of high community disease spread was found to be low yield, costly, and burdensome for the school district. Surveillance participation was low. A modified quarantine policy was not associated with increased in-school transmission. School funding may be better spent on targeted testing or other school expenses, especially with increasing vaccination rates.
在采取缓解措施的情况下，K-12 学校的 COVID-19 传播率最低。本研究旨在确定中学在全面实施普遍戴口罩的情况下恢复全日制面对面学习时的无症状 COVID-19 基准率，并评估实施监测测试的后勤障碍。
2021 年春季进行了为期 11 周的观察性队列研究，包括威斯康星州伍德县的 2288 名学生和教职员工。对同意接受测试的学生和教职员工进行 SARS-CoV-2 鼻聚合酶链反应检测，以确定疾病负担的基线情况。教师调查收集了学生戴口罩遵守情况和教室距离的数据。获得了阳性率、二次传播、隔离和距离政策、筛查参与率、成本和志愿者小时数要求等信息。评估了针对完全戴口罩的课堂暴露的修改后的隔离政策。
学生的阳性率平均为 3.0%（每周 0%-16.2%），教职员工的阳性率为 1.72%（每周 0%-6.9%）。在 163 名被隔离的人中，有 2 例疑似二次传播。每周平均有 15.6%的学校人群同意参加。学生之间的最小课堂距离为 2.7 至 5.5 英尺。学生戴口罩的遵守率大于 87%。该计划的成本为 106400 美元，需要大约 300 个志愿者小时。修改后的隔离政策规定，如果感染和暴露方戴口罩，学生在接触 COVID-19 病例后仍可继续参加面对面学校，不会导致额外传播。
在学生戴口罩的遵守率相对较高且学生之间距离有限的情况下，在社区疾病传播率较高的地区对学生和教职员工每周进行学校筛查被发现产量低、成本高且给学区带来负担。监测参与率低。修改后的隔离政策与校内传播增加无关。学校资金可能更好地用于有针对性的测试或其他学校费用，尤其是随着疫苗接种率的提高。
