TY - JOUR
T1 - A cluster randomised trial of cloth masks compared with medical masks in healthcare workers
AU - MacIntyre, C. Raina
AU - Seale, Holly
AU - Dung, Tham Chi
AU - Hien, Nguyen Tran
AU - Nga, Phan Thi
AU - Chughtai, Abrar Ahmad
AU - Rahman, Bayzidur
AU - Dwyer, Dominic E.
AU - Wang, Quanyi
N1 - Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
PY - 2015
Y1 - 2015
N2 - 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 ≥18 years 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 laboratory-confirmed 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 laboratory-confirmed 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. Trial registration number: Australian New Zealand Clinical Trials Registry: ACTRN12610000887077.
AB - 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 ≥18 years 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 laboratory-confirmed 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 laboratory-confirmed 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. Trial registration number: Australian New Zealand Clinical Trials Registry: ACTRN12610000887077.
UR - http://www.scopus.com/inward/record.url?scp=84929378804&partnerID=8YFLogxK
U2 - 10.1136/bmjopen-2014-006577
DO - 10.1136/bmjopen-2014-006577
M3 - Article
C2 - 25903751
AN - SCOPUS:84929378804
SN - 2044-6055
VL - 5
SP - 1
EP - 10
JO - BMJ Open
JF - BMJ Open
IS - 4
M1 - e006577
ER -