{"title":"相对湿度对粘质沙雷氏菌和牛分枝杆菌卡介苗气溶胶粒径和紫外线敏感性的影响","authors":"G. Ko, M.W. First, H.A. Burge","doi":"10.1054/tuld.2000.0249","DOIUrl":null,"url":null,"abstract":"<div><p><em>Setting</em>: A study of <em>Serratia marcescens</em> and BCG aerosols.</p><p><em>Objective</em>: To evaluate the effect of relative humidity (RH) on (1) the particle size and (2) sensitivity of 254nm germicidal ultraviolet (UV) irradiation.</p><p><em>Methods</em>: We built a RH controlled experimental chamber into which bacteria were aerosolized, exposed to varying amounts of UV irradiance over measured time periods, and quantitatively evaluated for viability. Aerosolized <em>Serratia marcescens</em> and bacille Calmette-Guérin (BCG) were subject to UV doses ranging from 57–829 μW · sec/cm<sup>2</sup>, and sampled with a six-stage Andersen culture plate impactor at RHs ranging from 25–95%.</p><p><em>Results</em>: Percent survival for both organisms was inversely related to UV dose. <em>Serratia marcescens</em> was more susceptible to UV than BCG under all conditions. More than 95% of the bacterial aerosol particles were 1.1–4.7 μm in aerodynamic diameter, and particles sizes increased from low (25–36%) to high (85–95%) RH. The count median diameter ranged from 1.9–2.6 μm for <em>Serratia marcescens</em> and from 2.2–2.7 μm for BCG as RH increased. For both <em>Serratia marcescens</em> and BCG, resistance to UV increased as RH increased. The UV resistance of both <em>Serratia marcescens</em> and BCG aerosols dramatically increased at RH higher than 85%.</p><p><em>Conclusions</em>: Our results indicate that differences in UV dose, kinds of microorganisms, airborne particle size and RH affect UV susceptibility.</p></div>","PeriodicalId":77450,"journal":{"name":"Tubercle and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease","volume":"80 4","pages":"Pages 217-228"},"PeriodicalIF":0.0000,"publicationDate":"2000-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1054/tuld.2000.0249","citationCount":"133","resultStr":"{\"title\":\"Influence of relative humidity on particle size and UV sensitivity of Serratia marcescens and Mycobacterium bovis BCG aerosols\",\"authors\":\"G. Ko, M.W. First, H.A. Burge\",\"doi\":\"10.1054/tuld.2000.0249\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p><em>Setting</em>: A study of <em>Serratia marcescens</em> and BCG aerosols.</p><p><em>Objective</em>: To evaluate the effect of relative humidity (RH) on (1) the particle size and (2) sensitivity of 254nm germicidal ultraviolet (UV) irradiation.</p><p><em>Methods</em>: We built a RH controlled experimental chamber into which bacteria were aerosolized, exposed to varying amounts of UV irradiance over measured time periods, and quantitatively evaluated for viability. Aerosolized <em>Serratia marcescens</em> and bacille Calmette-Guérin (BCG) were subject to UV doses ranging from 57–829 μW · sec/cm<sup>2</sup>, and sampled with a six-stage Andersen culture plate impactor at RHs ranging from 25–95%.</p><p><em>Results</em>: Percent survival for both organisms was inversely related to UV dose. <em>Serratia marcescens</em> was more susceptible to UV than BCG under all conditions. More than 95% of the bacterial aerosol particles were 1.1–4.7 μm in aerodynamic diameter, and particles sizes increased from low (25–36%) to high (85–95%) RH. The count median diameter ranged from 1.9–2.6 μm for <em>Serratia marcescens</em> and from 2.2–2.7 μm for BCG as RH increased. For both <em>Serratia marcescens</em> and BCG, resistance to UV increased as RH increased. The UV resistance of both <em>Serratia marcescens</em> and BCG aerosols dramatically increased at RH higher than 85%.</p><p><em>Conclusions</em>: Our results indicate that differences in UV dose, kinds of microorganisms, airborne particle size and RH affect UV susceptibility.</p></div>\",\"PeriodicalId\":77450,\"journal\":{\"name\":\"Tubercle and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease\",\"volume\":\"80 4\",\"pages\":\"Pages 217-228\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2000-08-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1054/tuld.2000.0249\",\"citationCount\":\"133\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Tubercle and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0962847900902491\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Tubercle and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0962847900902491","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Influence of relative humidity on particle size and UV sensitivity of Serratia marcescens and Mycobacterium bovis BCG aerosols
Setting: A study of Serratia marcescens and BCG aerosols.
Objective: To evaluate the effect of relative humidity (RH) on (1) the particle size and (2) sensitivity of 254nm germicidal ultraviolet (UV) irradiation.
Methods: We built a RH controlled experimental chamber into which bacteria were aerosolized, exposed to varying amounts of UV irradiance over measured time periods, and quantitatively evaluated for viability. Aerosolized Serratia marcescens and bacille Calmette-Guérin (BCG) were subject to UV doses ranging from 57–829 μW · sec/cm2, and sampled with a six-stage Andersen culture plate impactor at RHs ranging from 25–95%.
Results: Percent survival for both organisms was inversely related to UV dose. Serratia marcescens was more susceptible to UV than BCG under all conditions. More than 95% of the bacterial aerosol particles were 1.1–4.7 μm in aerodynamic diameter, and particles sizes increased from low (25–36%) to high (85–95%) RH. The count median diameter ranged from 1.9–2.6 μm for Serratia marcescens and from 2.2–2.7 μm for BCG as RH increased. For both Serratia marcescens and BCG, resistance to UV increased as RH increased. The UV resistance of both Serratia marcescens and BCG aerosols dramatically increased at RH higher than 85%.
Conclusions: Our results indicate that differences in UV dose, kinds of microorganisms, airborne particle size and RH affect UV susceptibility.