Department of Medicine - DIMED, Laboratory Medicine, University Hospital of Padua, Via Giustiniani 2, 35128, Padua, Italy.
Department of Laboratory Medicine, University-Hospital of Padua, Padua, Italy.
BMC Med. 2022 Feb 23;20(1):96. doi: 10.1186/s12916-022-02297-1.
The active surveillance of students is proposed as an effective strategy to contain SARS-CoV-2 spread and prevent schools' closure. Saliva for molecular testing is as sensitive as naso-pharyngeal swab (NPS), self-collected and well accepted by participants. This prospective study aimed to verify whether the active surveillance of the Padua University employees by molecular testing of self-collected saliva is an effective and affordable strategy for limiting SARS-CoV-2 spread.
A surveillance program based on self-collection of saliva every 2 weeks (October 2020-June 2021) was conducted. Among 8183 employees of the Padua University, a total of 6284 subjects voluntarily took part in the program. Eight collection points guaranteed the daily distribution and collection of barcoded salivary collection devices, which were delivered to the laboratory by a transport service for molecular testing. Quarantine of positive cases and contact tracing were promptly activated.
Among 6284 subjects, 206 individuals were SARS-CoV-2 positive (99 by salivary testing; 107 by NPS performed for contact tracing or symptoms). The cumulative SARS-CoV-2 incidence in this cohort was 3.1%, significantly lower than that of employees not in surveillance (8.0%), in Padua (7.1%) and in the Veneto region (7.2%). Employees with positive saliva results were asymptomatic or had mild symptoms. The levels of serum antibodies after 3 months from the infection were correlated with age and Ct values, being higher in older subjects with greater viral loads.
Salivary-based surveillance with contact tracing effectively allowed to limit SARS-CoV-2 contagion, also in a population with a high incidence.
主动监测学生被提议作为一种有效的策略，以遏制 SARS-CoV-2 的传播并防止学校关闭。用于分子检测的唾液与鼻咽拭子（NPS）一样敏感，可由参与者自行采集且被广泛接受。本前瞻性研究旨在验证通过自行采集的唾液进行分子检测对帕多瓦大学员工进行主动监测是否是一种限制 SARS-CoV-2 传播的有效且经济实惠的策略。
进行了一项基于每两周（2020 年 10 月至 2021 年 6 月）自行采集唾液的监测计划。在帕多瓦大学的 8183 名员工中，共有 6284 名员工自愿参加了该计划。8 个采集点保证了条码唾液采集装置的日常分发和采集，这些采集装置由运输服务及时送到实验室进行分子检测。对阳性病例进行隔离和接触者追踪。
在 6284 名受试者中，有 206 人（99 人通过唾液检测；107 人通过 NPS 检测进行接触者追踪或症状检查）为 SARS-CoV-2 阳性。该队列的累计 SARS-CoV-2 发病率为 3.1%，明显低于未进行监测的员工（8.0%）、帕多瓦（7.1%）和威尼托地区（7.2%）。唾液检测结果呈阳性的员工无症状或症状轻微。感染后 3 个月的血清抗体水平与年龄和 Ct 值相关，病毒载量越大的老年患者抗体水平越高。
通过接触者追踪进行基于唾液的监测可有效限制 SARS-CoV-2 的传播，即使在发病率较高的人群中也是如此。
