Cloth masks as respiratory protections in the COVID-19 pandemic period: evidence gaps

ABSTRACT Objective: to identify scientific evidence on the effectiveness of using cloth masks as safe protectors against COVID-19. Method: an integrative review of articles available in full obtained at PubMed, CINAHL, and Web of Science. Controlled, non-controlled descriptors and keywords such as “mask”, “home-made” and “cloth” or “cotton” and “infection control” or “infection prevention” were used. Results: thirty-eight articles were selected; of these, seven studies made up the sample. Evidence shows that cloth masks do not have the same protective characteristics as surgical masks, indicating an increased risk of infection due to humidity, diffusion of fluids, virus retention, and improper preparation. Considering the shortage of surgical masks during the pandemic, cloth masks could be proposed as a last resort. Conclusion: cloth masks should be used together with preventive measures, such as home insulation, good respiratory conduct, and regular hand hygiene.

摘要
研究目的：旨在明确布口罩作为抵御新型冠状病毒肺炎（COVID-19）的安全防护用品的有效性相关科学证据。
研究方法：本研究为整合性综述（integrative review），检索了PubMed、CINAHL、Web of Science三个数据库的完整公开文献。检索策略采用受控与非受控主题词及关键词组合，涵盖“mask（口罩）”、“home-made（自制）”与“cloth（织物）”或“cotton（棉）”，以及“infection control（感染控制）”或“infection prevention（感染预防）”。
研究结果：最终筛选纳入38篇文献，其中7项研究构成有效研究样本。研究证据表明，布口罩并不具备与外科口罩同等的防护性能，因湿度累积、液体渗透、病毒留存及制作不规范等因素，会提升感染风险。鉴于新冠疫情期间外科口罩的短缺状况，布口罩可作为备选防护方案。
研究结论：布口罩需与居家隔离、良好呼吸道礼仪及规范手卫生等其他预防措施联合使用。