02903nam a22003497a 4500 225 225 C000008 DOH 20200806155447.0 200325b ph ||||| |||| 00| 0 eng d DOH A cluster randomised trial of cloth masks compared with medical masks in healthcare workers / C Raina Macintyre [and eight others] BMJ Open, 2015. 10 pages [journal article] Includes bibliographic references. ABSTRACT Objective: The aim of this study was to compare the efficacy of cloth masks to medical masks in hospital healthcare workers (HCWs). The null hypothesis is that there is no difference between medical masks and cloth masks. Setting: 14 secondary-level/tertiary-level hospitals in Hanoi, Vietnam. Participants: 1607 hospital HCWs aged ≥18years working full-time in selected high-risk wards. Intervention: Hospital wards were randomised to: medical masks, cloth masks or a control group (usual practice, which included mask wearing). Participants used the mask on every shift for 4 consecutive weeks. Main outcome measure: Clinical respiratory illness (CRI), influenza-like illness (ILI) and laboratoryconfirmed respiratory virus infection. Results: The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratoryconfirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%. Conclusions: This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. This is an important finding to inform occupational health and safety. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection. Further research is needed to inform the widespread use of cloth masks globally. However, as a precautionary measure, cloth masks should not be recommended for HCWs, particularly in high-risk situations, and guidelines need to be updated. Masks Cloth Masks Medical Masks Surgical Masks Macintyre, C Raina Seale, Holly Tham, Chi Dung Nguyen, Tran Hien Phan, Thi Nga Chugtai, Abrar Ahmad Rahman, Bayzidur Dwyer, Dominic E. Wang, Quanyi https://bmjopen.bmj.com/content/bmjopen/5/4/e006577.full.pdf CV nlm