美国西奈山伊坎医学院Stuart C. Sealfon团队研究了检疫期间SARS-CoV-2在海军新兵中的传播。2020年11月11日，该研究发表在《新英格兰医学杂志》上。

在年轻人群中，控制SARS-CoV-2传播的公共卫生措施的有效性尚未可知。

研究组调查了美国海军陆战队新兵的SARS-CoV-2感染情况，这些新兵均在家中进行了为期2周的隔离，然后在封闭的营区内又进行了二次监督下为期2周的隔离，包括戴口罩、社交疏离以及日常温度和症状监测。到达营区当天或第2天、第7天、第14天分别对这些新兵的鼻拭子样本进行检测。研究组对从受感染新兵那里获得的病毒基因组进行系统发育分析，以鉴定流行簇并评估感染的流行病学特征。

共有1848名新兵自愿参加了这项研究；到达营区后的2天内，有16名（0.9％）SARS-CoV-2呈阳性，其中15名无症状。另有35名参与者（1.9％）在第7天或第14天检测呈阳性。在任一时间点检测阳性的51名新兵中，有5名（9.8％）在qPCR检测呈阳性前的一周出现症状。

拒绝参加研究的新兵中，有可用qPCR结果的1554名新兵中有26名（1.7％）在第14天检测呈阳性。通过日常症状监测进行的临床qPCR检测未发现SARS-CoV-2感染。对从32位参与者中获得的36个SARS-CoV-2基因组的分析揭示了18位参与者中的6个病毒流行簇。流行病学分析支持了多个局部传播事件，包括室友之间以及同一个排内新兵之间的传播。

研究结果表明，在海军陆战队的新兵中，大约有2％的人在有监督的隔离开始时曾对SARS-CoV-2产生阴性结果，而不到2％的先前状态未知的新兵在第14天检测呈阳性。检测为阳性的大多数新兵没有症状，且通过每日症状监测未发现病毒感染。

附：英文原文

Title: SARS-CoV-2 Transmission among Marine Recruits during Quarantine

Author: Andrew G. Letizia, M.D.,, Irene Ramos, Ph.D.,, Ajay Obla, Ph.D.,, Carl Goforth, Ph.D.,, Dawn L. Weir, Ph.D.,, Yongchao Ge, Ph.D.,, Marcas M. Bamman, Ph.D.,, Jayeeta Dutta, M.B.A.,, Ethan Ellis, B.S.,, Luis Estrella, Ph.D.,, Mary-Catherine George, Ph.D.,, Ana S. Gonzalez-Reiche, Ph.D.,, William D. Graham, Ph.D.,, Adriana van de Guchte, M.S.,, Ramiro Gutierrez, M.D.,, Franca Jones, Ph.D.,, Aspasia Kalomoiri, Ph.D.,, Rhonda Lizewski, M.D.,, Stephen Lizewski, Ph.D.,, Jan Marayag, B.A.,, Nada Marjanovic, M.S.,, Eugene V. Millar, Ph.D.,, Venugopalan D. Nair, Ph.D.,, German Nudelman, Ph.D.,, Edgar Nunez, A.S.,, Brian L. Pike, Ph.D.,, Chad Porter, Ph.D.,, James Regeimbal, Ph.D.,, Stas Rirak, M.S.,, Ernesto Santa Ana, A.S.,, Rachel S.G. Sealfon, Ph.D.,, Robert Sebra, Ph.D.,, Mark P. Simons, Ph.D.,, Alessandra Soares-Schanoski, Ph.D.,, Victor Sugiharto, Ph.D.,, Michael Termini, M.D.,, Sindhu Vangeti, Ph.D.,, Carlos Williams, M.D.,, Olga G. Troyanskaya, Ph.D.,, Harm van Bakel, Ph.D.,, and Stuart C. Sealfon, M.D.

Issue&Volume: 2020-11-11

Abstract:

BACKGROUND

The efficacy of public health measures to control the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not been well studied in young adults.

METHODS

We investigated SARS-CoV-2 infections among U.S. Marine Corps recruits who underwent a 2-week quarantine at home followed by a second supervised 2-week quarantine at a closed college campus that involved mask wearing, social distancing, and daily temperature and symptom monitoring. Study volunteers were tested for SARS-CoV-2 by means of quantitative polymerase-chain-reaction (qPCR) assay of nares swab specimens obtained between the time of arrival and the second day of supervised quarantine and on days 7 and 14. Recruits who did not volunteer for the study underwent qPCR testing only on day 14, at the end of the quarantine period. We performed phylogenetic analysis of viral genomes obtained from infected study volunteers to identify clusters and to assess the epidemiologic features of infections.

RESULTS

A total of 1848 recruits volunteered to participate in the study; within 2 days after arrival on campus, 16 (0.9%) tested positive for SARS-CoV-2, 15 of whom were asymptomatic. An additional 35 participants (1.9%) tested positive on day 7 or on day 14. Five of the 51 participants (9.8%) who tested positive at any time had symptoms in the week before a positive qPCR test. Of the recruits who declined to participate in the study, 26 (1.7%) of the 1554 recruits with available qPCR results tested positive on day 14. No SARS-CoV-2 infections were identified through clinical qPCR testing performed as a result of daily symptom monitoring. Analysis of 36 SARS-CoV-2 genomes obtained from 32 participants revealed six transmission clusters among 18 participants. Epidemiologic analysis supported multiple local transmission events, including transmission between roommates and among recruits within the same platoon.

CONCLUSIONS

Among Marine Corps recruits, approximately 2% who had previously had negative results for SARS-CoV-2 at the beginning of supervised quarantine, and less than 2% of recruits with unknown previous status, tested positive by day 14. Most recruits who tested positive were asymptomatic, and no infections were detected through daily symptom monitoring. Transmission clusters occurred within platoons.

DOI: 10.1056/NEJMoa2029717

Source: https://www.nejm.org/doi/full/10.1056/NEJMoa2029717