Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks
The coronavirus disease 2019 (COVID-19) pandemic is a general health crisis and has irreversible impacts on human societies. Globally, all people are at risk of being exposed to the novel coronavirus through transmission of airborne bioaerosols. Public health actions, such as wearing a mask, are hig...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-11-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/12/11/1496 |
| _version_ | 1797511247231451136 |
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| author | Eun-Hee Lee Yunsoo Chang Seung-Woo Lee |
| author_facet | Eun-Hee Lee Yunsoo Chang Seung-Woo Lee |
| author_sort | Eun-Hee Lee |
| collection | DOAJ |
| description | The coronavirus disease 2019 (COVID-19) pandemic is a general health crisis and has irreversible impacts on human societies. Globally, all people are at risk of being exposed to the novel coronavirus through transmission of airborne bioaerosols. Public health actions, such as wearing a mask, are highly recommended to reduce the transmission of infectious diseases. The appropriate use of masks is necessary for effectively preventing the transmission of airborne bioaerosols. The World Health Organization (WHO) suggests washing fabric masks or throwing away disposable masks after they are used. However, people often use masks more than once without washing or disposing them. The prolonged use of a single mask might—as a result of the user habitually touching the mask—promote the spread of pathogens from airborne bioaerosols that have accumulated on the mask. Therefore, it is necessary to evaluate how long the living components of bioaerosols can be viable on the masks. Here, we evaluated the viability of airborne <i>Bacillus subtilis</i> (<i>B. subtilis</i>) in bioaerosols filtered on woven and anti-droplet (non-woven) face masks. As a simulation of being simultaneously exposed to sand dust and bioaerosols, the viability rates of bioaerosols that had accumulated on masks were also tested against fine dust and airborne droplets containing bacteria. The bioaerosols survived on the masks immediately after the masks were used to filter the bioaerosols, and the bacteria significantly proliferated after one day of storage. Thereafter, the number of viable cells in the filtered bioaerosols gradually decreased over time, and the viability of <i>B. subtilis</i> in bioaerosols on the masks varied, depending on the mask material used (woven or non-woven). Despite the reduction in viability, bioaerosols containing living components were still found in both woven and anti-droplet masks even after six days of storage and it took nine days not to have found them on masks. The number of viable cells in bioaerosols on masks significantly decreased upon exposure of the masks to fine dust. The results of this study should provide useful information on how to appropriately use masks to increase their duration of effectiveness against bioaerosols. |
| first_indexed | 2024-03-10T05:42:40Z |
| format | Article |
| id | doaj.art-dc696169e4cb4209951378c557d0b093 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-03-10T05:42:40Z |
| publishDate | 2021-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-dc696169e4cb4209951378c557d0b0932023-11-22T22:25:16ZengMDPI AGAtmosphere2073-44332021-11-011211149610.3390/atmos12111496Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face MasksEun-Hee Lee0Yunsoo Chang1Seung-Woo Lee2Department of Microbiology, Pusan National University, 2 Busandaehak-ro 63 beon-gil, Geumjeong-gu, Busan 46241, KoreaDepartment of Microbiology, Pusan National University, 2 Busandaehak-ro 63 beon-gil, Geumjeong-gu, Busan 46241, KoreaDepartment of Fine Chemistry, Seoul National University of Science and Technology, Seoul 01811, KoreaThe coronavirus disease 2019 (COVID-19) pandemic is a general health crisis and has irreversible impacts on human societies. Globally, all people are at risk of being exposed to the novel coronavirus through transmission of airborne bioaerosols. Public health actions, such as wearing a mask, are highly recommended to reduce the transmission of infectious diseases. The appropriate use of masks is necessary for effectively preventing the transmission of airborne bioaerosols. The World Health Organization (WHO) suggests washing fabric masks or throwing away disposable masks after they are used. However, people often use masks more than once without washing or disposing them. The prolonged use of a single mask might—as a result of the user habitually touching the mask—promote the spread of pathogens from airborne bioaerosols that have accumulated on the mask. Therefore, it is necessary to evaluate how long the living components of bioaerosols can be viable on the masks. Here, we evaluated the viability of airborne <i>Bacillus subtilis</i> (<i>B. subtilis</i>) in bioaerosols filtered on woven and anti-droplet (non-woven) face masks. As a simulation of being simultaneously exposed to sand dust and bioaerosols, the viability rates of bioaerosols that had accumulated on masks were also tested against fine dust and airborne droplets containing bacteria. The bioaerosols survived on the masks immediately after the masks were used to filter the bioaerosols, and the bacteria significantly proliferated after one day of storage. Thereafter, the number of viable cells in the filtered bioaerosols gradually decreased over time, and the viability of <i>B. subtilis</i> in bioaerosols on the masks varied, depending on the mask material used (woven or non-woven). Despite the reduction in viability, bioaerosols containing living components were still found in both woven and anti-droplet masks even after six days of storage and it took nine days not to have found them on masks. The number of viable cells in bioaerosols on masks significantly decreased upon exposure of the masks to fine dust. The results of this study should provide useful information on how to appropriately use masks to increase their duration of effectiveness against bioaerosols.https://www.mdpi.com/2073-4433/12/11/1496wovenfabricanti-dropletfacepiecebioaerosolsurvival |
| spellingShingle | Eun-Hee Lee Yunsoo Chang Seung-Woo Lee Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks Atmosphere woven fabric anti-droplet facepiece bioaerosol survival |
| title | Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks |
| title_full | Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks |
| title_fullStr | Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks |
| title_full_unstemmed | Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks |
| title_short | Viability of <i>Bacillus subtilis</i> Cells in Airborne Bioaerosols on Face Masks |
| title_sort | viability of i bacillus subtilis i cells in airborne bioaerosols on face masks |
| topic | woven fabric anti-droplet facepiece bioaerosol survival |
| url | https://www.mdpi.com/2073-4433/12/11/1496 |
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