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

• DOI: 10.1371/journal.pone.0240287
• Publication Date: 2020-10-13T13:40:40Z
• Authors: 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
• Keywords: Hajj; Rhinovirus

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 'facemask' or 'no facemask' group. Fifty offered participants intervention tents, be worn over four days, none control tents. All recorded facemask use symptoms health diaries. Nasal swabs collected from symptomatic for virus detection by reverse transcription polymerase chain reaction. Clinical laboratory analyzed 'intention- to-treat' 'per-protocol'. A total 7687 adult 318 randomized: 3864 149 group, 3823 169 Participants aged 18 95 (median 34, mean 37) years, with a male female ratio 1:1.2. Overall, viruses detected 277 650 (43%) nasal/pharyngeal pilgrims. Common rhinovirus (35.1%), influenza (4.5%) parainfluenza (1.7%). arm, respectively 954 (24.7%) 1842 (47.7%) used daily intermittently, while 546 (14.3%) 1334 (34.9%) intermittently. By intention-to-treat analysis, did not seem effective laboratory-confirmed infections (odds [OR], 1.4; 95% confidence interval [CI], 0.9 2.1, p = 0.18) nor clinical infection (OR, 1.1; CI, 1.4, 0.40). Similarly, per-protocol (OR 1.2, CI 0.9–1.7, 0.26) 1.3, 1.0–1.8, 0.06). Conclusion This was unable provide conclusive evidence on efficacy most likely due poor adherence protocol.