Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada; Department of Medicine, McMaster University, Hamilton, ON, Canada; The Research Institute of St Joe's Hamilton, Hamilton, ON, Canada.
Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada; Department of Internal Medicine, American University of Beirut, Beirut, Lebanon; Clinical Research Institute, American University of Beirut, Beirut, Lebanon.
Lancet. 2020 Jun 27;395(10242):1973-1987. doi: 10.1016/S0140-6736(20)31142-9. Epub 2020 Jun 1.
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.
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.
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=25 697 patients). Transmission of viruses was lower with physical distancing of 1 m or more, compared with a distance of less than 1 m (n=10 736, 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; p=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; p=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.
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.
World Health Organization.
严重急性呼吸系统综合征冠状病毒 2 型（SARS-CoV-2）会引发 COVID-19，通过密切接触在人与人之间传播。我们旨在研究在医疗和非医疗（例如社区）环境中，保持身体距离、佩戴口罩和眼部防护对病毒传播的影响。
我们进行了系统评价和荟萃分析，以研究避免人与人之间病毒传播的最佳距离，并评估使用口罩和眼部防护来预防病毒传播的效果。我们从 21 个标准的世卫组织特定和 COVID-19 特定来源中获取了 SARS-CoV-2 和引起严重急性呼吸系统综合征和中东呼吸综合征的β冠状病毒的数据。我们从数据库成立到 2020 年 5 月 3 日进行了无语言限制的搜索，用于比较研究以及可接受性、可行性、资源利用和公平性的背景因素。我们对记录进行了筛选、提取数据，并进行了重复的偏倚风险评估。我们进行了频率论和贝叶斯荟萃分析以及随机效应荟萃回归。我们根据 Cochrane 方法和 GRADE 方法对证据的确定性进行了评级。本研究在 PROSPERO 注册，CRD42020177047。
我们的搜索在 16 个国家和六大洲共确定了 172 项观察性研究，没有随机对照试验，在医疗和非医疗环境中有 44 项相关的比较研究（n=25697 例患者）。与距离小于 1 m 的情况相比，保持 1 m 或更大的身体距离时，病毒传播的可能性较低（n=10696 例，汇总调整后的优势比[OR]0.18，95%CI0.09 至 0.38；风险差异[RD]-10.2%，95%CI-11.5 至-7.5；中等确定性）；随着距离的增加，保护作用增强（相对风险[RR]每增加 1 m 增加 2.02；p=0.041；中等确定性）。口罩的使用可能会大大降低感染风险（n=2647 例；OR0.15，95%CI0.07 至 0.34，RD-14.3%，-15.9 至-10.7；低确定性），与 N95 或类似的呼吸器相比，与一次性手术口罩或类似口罩（例如可重复使用的 12-16 层棉口罩；p=0.090；后验概率>95%，低确定性）的关联更强。眼部防护也与感染减少有关（n=3713 例；OR0.22，95%CI0.12 至 0.39，RD-10.6%，95%CI-12.5 至-7.7；低确定性）。未调整的研究和亚组及敏感性分析得出了类似的结果。
本系统评价和荟萃分析的结果支持保持 1 m 或更大的身体距离，并为模型和接触者追踪提供定量估计，以提供政策信息。在公共和医疗环境中，应根据这些发现和背景因素，优化口罩、呼吸器和眼部防护的使用。需要进行强有力的随机对照试验，以更好地为这些干预措施提供证据，但本系统评估目前最佳现有证据可能会为临时指导提供信息。
世界卫生组织。
Zotero 插件
