Surgical Face Masks Worn By Multidrug-Resistant Tuberculosis Patients: Impact on Infectivity of Air on a Hospital Ward.
Am J Respir Crit Care Med. 2012 Feb 9;
Authors: Dharmadhikari AS, Mphahlele M, Stoltz A, Venter K, Mathebula R, Masotla T, Lubbe W, Pagano M, First M, Jensen PA, van der Walt M, Nardell EA
Abstract
RATIONALE AND OBJECTIVES: Drug-resistant tuberculosis transmission in hospitals threatens staff and patient health. Surgical face masks used by TB patients are believed to reduce transmission, but have not been rigorously tested. We sought to quantify their efficacy when worn by multidrug resistant tuberculosis (MDR-TB) patients. METHODS: Over 3 months, 17 pulmonary MDR-TB patients occupied an MDR-TB ward in South Africa and wore face masks on alternate days. Ward air was exhausted to two identical chambers each housing 90 pathogen-free guinea pigs that breathed ward air either when patients wore surgical face masks (intervention group) or when patients did not wear masks (control group). Efficacy was based on differences in guinea pig infections in each chamber. MEASUREMENTS AND MAIN RESULTS: 69/90 control guinea pigs (76.6%; 95% CI: 68 - 85%) became infected, compared to 36/90 intervention guinea pigs (40%; 95% CI: 31 - 51%), representing a 56% (95% CI: 33% - 70.5%) decreased risk of tuberculosis transmission when patients used masks. CONCLUSIONS: Surgical face masks on MDR-TB patients significantly reduced transmission and offer an adjunct measure for reducing TB transmission from infectious patients.
PMID: 22323300 [PubMed - as supplied by publisher]