Sharma Suresh K, Mishra Mayank, Mudgal Shiv K
College of Nursing, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India.
Department of Pulmonary Medicine, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India.
J Educ Health Promot. 2020 Jul 28;9:192. doi: 10.4103/jehp.jehp_533_20. eCollection 2020.
Novel coronavirus is believed to be tiny enough (0.08-0.14 μm) to penetrate through face mask, thus protection offered by cloth mask may be too low. However, the use of cloth face mask in community has been recommended by the United States Centre for Disease Control and Prevention and regulatory bodies of other countries. There is paucity of literature on efficacy of cloth face mask in preventing SARS-CoV-2 infection transmission; thus, this review aims to update the available most recent evidences on efficacy of cloth face masks in prevention of viral infection transmission.
We searched MEDLINE, EMBASE, and Clinical Trials Register for identifying studies related to this review using free-text terms and MeSH terms. Both experimental and observational studies on efficacy of cloth masks which were published in English language have been included in this review except expert opinions, commentaries, editorials, and review articles. Twelve studies were eligible to be included in review for data extraction and qualitative synthesis was carried out from extracted data but quantitative analysis (meta-analysis) could not be performed because of serious heterogeneity between the studies.
Cloth face masks show minimum efficacy in source control than the medical grade mask. The efficacy of cloth face masks filtration varies and depends on the type of material used, number of layers, and degree of moisture in mask and fitting of mask on face.
Cloth face masks have limited efficacy in combating viral infection transmission. However, it may be used in closed, crowded indoor, and outdoor public spaces involving physical proximity to prevent spread of SARS-CoV-2 infection.
新型冠状病毒据信足够微小（0.08 - 0.14微米），能够穿透口罩，因此布口罩提供的防护可能过低。然而，美国疾病控制与预防中心以及其他国家的监管机构已建议在社区使用布口罩。关于布口罩预防SARS-CoV-2感染传播效果的文献较少；因此，本综述旨在更新有关布口罩预防病毒感染传播效果的最新现有证据。
我们在MEDLINE、EMBASE和临床试验注册库中进行检索，使用自由文本词和医学主题词来识别与本综述相关的研究。本综述纳入了所有以英文发表的关于布口罩效果的实验性和观察性研究，但不包括专家意见、评论、社论和综述文章。有12项研究符合纳入综述进行数据提取的条件，并对提取的数据进行了定性综合分析，但由于研究之间存在严重异质性，无法进行定量分析（荟萃分析）。
与医用级口罩相比，布口罩在源头控制方面显示出最低的效果。布口罩的过滤效果各不相同，取决于所用材料的类型、层数、口罩的湿度程度以及口罩与面部的贴合度。
布口罩在抗击病毒感染传播方面效果有限。然而，它可用于封闭、拥挤的室内和室外公共场所，在这些场所中人们存在身体上的近距离接触，以防止SARS-CoV-2感染的传播。
