加拿大麦克马斯特大学Holger J Schünemann团队分析了物理距离、口罩和护目镜预防SARS-CoV-2和COVID-19人际传播的效果。2020年6月1日出版的《柳叶刀》杂志发表了这项成果。

SARS-CoV-2会引起COVID-19，并通过密切接触在人与人之间传播。研究组旨在调查在医疗保健和非医疗保健（例如社区）环境中物理距离、口罩和护目镜对病毒传播的影响。

研究组进行了系统审查和荟萃分析，以研究避免人与人之间病毒传播的最佳距离，并评估使用口罩和护目镜以防止病毒传播的效果。研究组从21种标准的WHO特刊和COVID-19特刊数据库中检索从建库至2020年5月3日发布的冠状病毒的研究，筛选记录，提取数据，并评估了重复的偏倚风险。

研究组确定了在16个国家和六大洲进行的172项观察性研究，没有随机对照试验，44项是针对医疗和非医疗机构（25697名患者）的相关比较研究。与小于1 m的物理距离相比，距离1 m或更远时病毒的传播率较低，且随着距离的延长，保护程度显著增加。使用口罩可大大降低感染风险，与一次性外科口罩或类似口罩相比，N95或类似口罩降低风险的程度更大。使用护目镜也可显著降低感染风险。未经校正的研究以及亚组和敏感性分析均显示了相似的结果。

该研究结果支持保持1 m及以上的社交距离，在公共场所和卫生保健场所最好使用口罩、人工呼吸器和护目镜。

附：英文原文

Title: Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis

Author: Derek K Chu, Elie A Akl, Stephanie Duda, Karla Solo, Sally Yaacoub, Holger J Schünemann, Derek K Chu, Elie A Akl, Amena El-harakeh, Antonio Bognanni, Tamara Lotfi, Mark Loeb, Anisa Hajizadeh, Anna Bak, Ariel Izcovich, Carlos A Cuello-Garcia, Chen Chen, David J Harris, Ewa Borowiack, Fatimah Chamseddine, Finn Schünemann, Gian Paolo Morgano, Giovanna E U Muti Schünemann, Guang Chen, Hong Zhao, Ignacio Neumann, Jeffrey Chan, Joanne Khabsa, Layal Hneiny, Leila Harrison, Maureen Smith, Nesrine Rizk, Paolo Giorgi Rossi, Pierre AbiHanna, Rayane El-khoury, Rosa Stalteri, Tejan Baldeh, Thomas Piggott, Yuan Zhang, Zahra Saad, Assem Khamis, Marge Reinap, Stephanie Duda, Karla Solo, Sally Yaacoub, Holger J Schünemann

Issue&Volume: 2020-06-01

Abstract: Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 and is spread person-to-person through close contact. We aimed to investigate the effects of physical distance, face masks, and eye protection on virus transmission in health-care and non-health-care (eg, community) settings.

Methods

We did a systematic review and meta-analysis to investigate the optimum distance for avoiding person-to-person virus transmission and to assess the use of face masks and eye protection to prevent transmission of viruses. We obtained data for SARS-CoV-2 and the betacoronaviruses that cause severe acute respiratory syndrome, and Middle East respiratory syndrome from 21 standard WHO-specific and COVID-19-specific sources. We searched these data sources from database inception to May 3, 2020, with no restriction by language, for comparative studies and for contextual factors of acceptability, feasibility, resource use, and equity. We screened records, extracted data, and assessed risk of bias in duplicate. We did frequentist and Bayesian meta-analyses and random-effects meta-regressions. We rated the certainty of evidence according to Cochrane methods and the GRADE approach. This study is registered with PROSPERO, CRD42020177047.

Findings

Our search identified 172 observational studies across 16 countries and six continents, with no randomised controlled trials and 44 relevant comparative studies in health-care and non-health-care settings (n=25697 patients). Transmission of viruses was lower with physical distancing of 1 m or more, compared with a distance of less than 1 m (n=10736, pooled adjusted odds ratio [aOR] 0·18, 95% CI 0·09 to 0·38; risk difference [RD] 10·2%, 95% CI 11·5 to 7·5; moderate certainty); protection was increased as distance was lengthened (change in relative risk [RR] 2·02 per m; pinteraction=0·041; moderate certainty). Face mask use could result in a large reduction in risk of infection (n=2647; aOR 0·15, 95% CI 0·07 to 0·34, RD 14·3%, 15·9 to 10·7; low certainty), with stronger associations with N95 or similar respirators compared with disposable surgical masks or similar (eg, reusable 12–16-layer cotton masks; pinteraction=0·090; posterior probability >95%, low certainty). Eye protection also was associated with less infection (n=3713; aOR 0·22, 95% CI 0·12 to 0·39, RD 10·6%, 95% CI 12·5 to 7·7; low certainty). Unadjusted studies and subgroup and sensitivity analyses showed similar findings.

Interpretation

The findings of this systematic review and meta-analysis support physical distancing of 1 m or more and provide quantitative estimates for models and contact tracing to inform policy. Optimum use of face masks, respirators, and eye protection in public and health-care settings should be informed by these findings and contextual factors. Robust randomised trials are needed to better inform the evidence for these interventions, but this systematic appraisal of currently best available evidence might inform interim guidance.

DOI: 10.1016/S0140-6736(20)31142-9

Source: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext