Min-Chul Kim1, Seongman Bae2, Ji Yeun Kim2, Se Yoon Park3, Joon Seo Lim4, Minki Sung5, Sung-Han Kim2. 1. Division of Infectious Diseases, Department of Internal Medicine, Chung-Ang University Hospital, Seoul, South Korea. 2. Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. 3. Division of Infectious Diseases, Department of Internal Medicine, Soonchunhyang University Seoul Hospital, Soonchunhyang University College of Medicine, Seoul, South Korea. 4. Clinical Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. 5. Department of Architectural Engineering, Sejong University, Seoul, South Korea.
Abstract
BACKGROUND: Data on the filtration efficacies of various masks against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are limited. We thus evaluate the effectiveness of the surgical mask, the N95 respirator mask, and its equivalent (KF94 mask) in filtering SARS-CoV-2. METHODS: Patients hospitalised with SARS-CoV-2 infection were instructed to cough five times each while wearing (1) no mask, (2) surgical mask, (3) KF94 mask, and (4) N95 mask. The coughs were separated by 20-second intervals, and the patients were rested for at least 5 min between each setting. SARS-CoV-2 viral loads in patient samples (i.e. nasopharyngeal swabs and saliva), petri dishes placed in front of the patients during coughing, and swabs from the outer and inner surfaces of the masks were analysed with PCR. RESULTS: A total of 7 patients with SARS-CoV-2 infection participated in the mask test. SARS-CoV-2 was detected on the petri dishes after coughing in 3 out of 7 cases with the surgical mask or no mask. Viral particles were not found in the petri dishes after coughing while wearing the N95 mask or the KF94 mask. While viral particles were detected in both the inner and outer surfaces of the surgical masks, those were detected only in the inner surfaces of the N95 and K94 masks. CONCLUSION: Surgical masks were less effective in filtering viral particles from coughing patients with SARS-CoV-2 infection. N95 masks and its equivalents efficiently blocked SARS-CoV-2 particles from coughing patients.
BACKGROUND: Data on the filtration efficacies of various masks against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are limited. We thus evaluate the effectiveness of the surgical mask, the N95 respirator mask, and its equivalent (KF94 mask) in filtering SARS-CoV-2. METHODS:Patients hospitalised with SARS-CoV-2 infection were instructed to cough five times each while wearing (1) no mask, (2) surgical mask, (3) KF94 mask, and (4) N95 mask. The coughs were separated by 20-second intervals, and the patients were rested for at least 5 min between each setting. SARS-CoV-2 viral loads in patient samples (i.e. nasopharyngeal swabs and saliva), petri dishes placed in front of the patients during coughing, and swabs from the outer and inner surfaces of the masks were analysed with PCR. RESULTS: A total of 7 patients with SARS-CoV-2 infection participated in the mask test. SARS-CoV-2 was detected on the petri dishes after coughing in 3 out of 7 cases with the surgical mask or no mask. Viral particles were not found in the petri dishes after coughing while wearing the N95 mask or the KF94 mask. While viral particles were detected in both the inner and outer surfaces of the surgical masks, those were detected only in the inner surfaces of the N95 and K94 masks. CONCLUSION: Surgical masks were less effective in filtering viral particles from coughingpatients with SARS-CoV-2 infection. N95 masks and its equivalents efficiently blocked SARS-CoV-2 particles from coughingpatients.
Authors: Patricia E Lee; Robert Kozak; Nasrin Alavi; Hamza Mbareche; Rose C Kung; Kellie E Murphy; Darian Perruzza; Stephanie Jarvi; Elsa Salvant; Noor Niyar N Ladhani; Albert J M Yee; Louise-Helene Gagnon; Richard Jenkinson; Grace Y Liu Journal: CMAJ Open Date: 2022-05-24
Authors: Dosup Kim; Jae-Hoon Ko; Kyong Ran Peck; Jin Yang Baek; Hee-Won Moon; Hyun Kyun Ki; Ji Hyun Yoon; Hyo Jin Kim; Jeong Hwa Choi; Ga Eun Park Journal: Int J Environ Res Public Health Date: 2021-06-16 Impact factor: 3.390