Facemask against viral respiratory infections among Hajj pilgrims: A challenging cluster-randomized trial

Mohammad Alfelali; Elizabeth A Haworth; Osamah Barasheed; Al-Mamoon Badahdah; Hamid Bokhary; Mohamed Tashani; Mohammad I Azeem; Jen Kok; Janette Taylor; Elizabeth H Barnes; Haitham El Bashir; Gulam Khandaker; Edward C Holmes; Dominic E Dwyer; Leon G Heron; Godwin J Wilson; Robert Booy; Harunor Rashid; Hajj Research Team

doi:10.1371/journal.pone.0240287

Facemask against viral respiratory infections among Hajj pilgrims: A challenging cluster-randomized trial

PLoS One. 2020 Oct 13;15(10):e0240287. doi: 10.1371/journal.pone.0240287. eCollection 2020.

Authors

Mohammad Alfelali^{1

2}, Elizabeth A Haworth³, Osamah Barasheed^{1

4}, Al-Mamoon Badahdah^{1

2}, Hamid Bokhary^{5

6}, Mohamed Tashani^{7

8}, Mohammad I Azeem¹, Jen Kok^{5

9}, Janette Taylor⁹, Elizabeth H Barnes¹⁰, Haitham El Bashir¹¹, Gulam Khandaker^{7

12}, Edward C Holmes⁵, Dominic E Dwyer^{5

9}, Leon G Heron¹, Godwin J Wilson¹³, Robert Booy^{1

5}, Harunor Rashid^{1

5}; Hajj Research Team

Affiliations

¹ National Centre for Immunisation Research and Surveillance, The Children's Hospital at Westmead and The University of Sydney, Sydney, New South Wales, Australia.
² Department of Family and Community Medicine, Faculty of Medicine in Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia.
³ Menzies Institute for Medical Research Tasmania, Hobart, Tasmania, Australia.
⁴ Research Center, King Abdullah Medical City, Mecca, Saudi Arabia.
⁵ Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Life & Environmental Sciences and School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia.
⁶ Umm Al-Qura University, Mecca, Saudi Arabia.
⁷ Discipline of Child and Adolescent Health, The Children's Hospital at Westmead Clinical School, Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia.
⁸ Faculty of Medicine, The University of Tripoli, Ain Zara, Tripoli, Libya.
⁹ NSW Health Pathology - Institute for Clinical Pathology and Medical Research, Westmead Hospital and The University of Sydney, Sydney, New South Wales, Australia.
¹⁰ NHMRC Clinical Trials Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.
¹¹ Rehabilitation Department, Al Jalila Children Specialty Hospital, Dubai, United Arab Emirates.
¹² Central Queensland Public Health Unit, Central Queensland Hospital and Health Service, Rockhampton, Queensland, Australia.
¹³ Department of Laboratory Medicine, Hamad Medical Corporation, Doha, Qatar.

Abstract

Background: In this large-scale cluster-randomized controlled trial (cRCT) we sought to assess the effectiveness of facemasks against viral respiratory infections.

Methods and results: Over three consecutive Hajj seasons (2013, 2014, 2015) pilgrims' tents in Makkah were allocated to 'facemask' or 'no facemask' group. Fifty facemasks were offered to participants in intervention tents, to be worn over four days, and none were offered to participants in control tents. All participants recorded facemask use and respiratory symptoms in health diaries. Nasal swabs were collected from the symptomatic for virus detection by reverse transcription polymerase chain reaction. Clinical symptoms and laboratory results were analyzed by 'intention- to-treat' and 'per-protocol'. A total of 7687 adult participants from 318 tents were randomized: 3864 from 149 tents to the intervention group, and 3823 from 169 tents to the control group. Participants were aged 18 to 95 (median 34, mean 37) years, with a male to female ratio of 1:1.2. Overall, respiratory viruses were detected in 277 of 650 (43%) nasal/pharyngeal swabs collected from symptomatic pilgrims. Common viruses were rhinovirus (35.1%), influenza (4.5%) and parainfluenza (1.7%). In the intervention arm, respectively 954 (24.7%) and 1842 (47.7%) participants used facemasks daily and intermittently, while in the control arm, respectively 546 (14.3%) and 1334 (34.9%) used facemasks daily and intermittently. By intention-to-treat analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (odds ratio [OR], 1.4; 95% confidence interval [CI], 0.9 to 2.1, p = 0.18) nor against clinical respiratory infection (OR, 1.1; 95% CI, 0.9 to 1.4, p = 0.40). Similarly, in a per-protocol analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (OR 1.2, 95% CI 0.9-1.7, p = 0.26) nor against clinical respiratory infection (OR 1.3, 95% CI 1.0-1.8, p = 0.06).

Conclusion: This trial was unable to provide conclusive evidence on facemask efficacy against viral respiratory infections most likely due to poor adherence to protocol.

Publication types

Randomized Controlled Trial
Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Adult
Aged
Aged, 80 and over
Confidence Intervals
Female
Humans
Male
Masks*
Middle Aged
Odds Ratio
Respiratory Tract Infections / epidemiology*
Respiratory Tract Infections / prevention & control*
Saudi Arabia / epidemiology
Young Adult

Grants and funding

This report was made possible by a National Priorities Research Program grant (NPRP 6- 1505-3-358) from the Qatar National Research Fund, a member of Qatar Foundation. The grant was offered to HR, RB, EAH, HE-B, OB, GJW, DED, ECH, and LGH. This body was not involved in the study design study design, data collection and analysis, decision to publish, or preparation of the manuscript.