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Sanmark E, Tuhkuri-Matvejeff A, Geneid A, Oksanen LM, Alku P, Hakala J, Heikkilä P, Silvonen V, Taipale A, Rönkkö T, Laukkanen AM, Saari S, Vartiainen VA. Effect of Vocalization on Human Aerosol Dynamics: Whispering Produces More Aerosols than Speaking. J Voice 2024:S0892-1997(24)00239-X. [PMID: 39142922 DOI: 10.1016/j.jvoice.2024.07.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Revised: 07/24/2024] [Accepted: 07/24/2024] [Indexed: 08/16/2024]
Abstract
OBJECTIVES Sound pressure and exhaled flow have been identified as important factors associated with higher particle emissions. The aim of this study was to assess how different vocalizations affect the particle generation independently from other factors. DESIGN Experimental study. METHODS Thirty-three experienced singers repeated two different sentences in normal loudness and whispering. The first sentence consisted mainly of consonants like /k/ and /t/ as well as open vowels, while the second sentence also included the /s/ sound and contained primarily closed vowels. The particle emission was measured using condensation particle counter (CPC, 3775 TSI Inc.) and aerodynamic particle sizer (APS, 3321 TSI Inc.). The CPC measured particle number concentration for particles larger than 4 nm and mainly reflects the number of particles smaller than 0.5 µm since these particles dominate total number concentration. The APS measured particle size distribution and number concentration in the size range of 0.5-10 µm and data were divided into >1 µm and <1 µm particle size ranges. Generalized linear mixed-effects models were constructed to assess the factors affecting particle generation. RESULTS Whispering produced more particles than speaking and sentence 1 produced more particles than sentence 2 while speaking. Sound pressure level had effect on particle production independently from vocalization. The effect of exhaled airflow was not statistically significant. CONCLUSIONS Based on our results the type of vocalization has a significant effect on particle production independently from other factors such as sound pressure level.
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Affiliation(s)
- Enni Sanmark
- Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Anna Tuhkuri-Matvejeff
- Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Ahmed Geneid
- Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Lotta-Maria Oksanen
- Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Otorhinolaryngology and Phoniatrics - Head and Neck Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Paavo Alku
- Department of Information and Communications Engineering, Aalto University, Espoo, Finland
| | - Jani Hakala
- VTT Technical Reseach Centre of Finland, Tampere, Finland
| | - Paavo Heikkilä
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
| | - Ville Silvonen
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
| | - Aimo Taipale
- VTT Technical Reseach Centre of Finland, Tampere, Finland
| | - Topi Rönkkö
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
| | - Anne-Maria Laukkanen
- Speech and Voice Research Laboratory, Faculty of Social Sciences, Tampere University, Tampere, Finland
| | - Sampo Saari
- Tampere University of Applied Sciences, Tampere, Finland
| | - Ville A Vartiainen
- Faculty of Medicine, University of Helsinki, Helsinki, Finland; Heart and Lung Center, Helsinki University Hospital, Helsinki, Finland.
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Roe T, Silveira S, Luo Z, Osborne EL, Senthil Murugan G, Grocott MPW, Postle AD, Dushianthan A. Particles in Exhaled Air (PExA): Clinical Uses and Future Implications. Diagnostics (Basel) 2024; 14:972. [PMID: 38786270 PMCID: PMC11119244 DOI: 10.3390/diagnostics14100972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 04/29/2024] [Accepted: 05/03/2024] [Indexed: 05/25/2024] Open
Abstract
Access to distal airway samples to assess respiratory diseases is not straightforward and requires invasive procedures such as bronchoscopy and bronchoalveolar lavage. The particles in exhaled air (PExA) device provides a non-invasive means of assessing small airways; it captures distal airway particles (PEx) sized around 0.5-7 μm and contains particles of respiratory tract lining fluid (RTLF) that originate during airway closure and opening. The PExA device can count particles and measure particle mass according to their size. The PEx particles can be analysed for metabolites on various analytical platforms to quantitatively measure targeted and untargeted lung specific markers of inflammation. As such, the measurement of distal airway components may help to evaluate acute and chronic inflammatory conditions such as asthma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, and more recently, acute viral infections such as COVID-19. PExA may provide an alternative to traditional methods of airway sampling, such as induced sputum, tracheal aspirate, or bronchoalveolar lavage. The measurement of specific biomarkers of airway inflammation obtained directly from the RTLF by PExA enables a more accurate and comprehensive understanding of pathophysiological changes at the molecular level in patients with acute and chronic lung diseases.
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Affiliation(s)
- Thomas Roe
- General Intensive Care Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Siona Silveira
- Perioperative and Critical Care Theme, NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Zixing Luo
- Perioperative and Critical Care Theme, NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Optoelectronics Research Centre, University of Southampton, Southampton SO17 1BJ, UK
| | - Eleanor L Osborne
- Optoelectronics Research Centre, University of Southampton, Southampton SO17 1BJ, UK
| | | | - Michael P W Grocott
- General Intensive Care Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Perioperative and Critical Care Theme, NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Anthony D Postle
- Perioperative and Critical Care Theme, NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Ahilanandan Dushianthan
- General Intensive Care Unit, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Perioperative and Critical Care Theme, NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
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Andrup L, Krogfelt KA, Stephansen L, Hansen KS, Graversen BK, Wolkoff P, Madsen AM. Reduction of acute respiratory infections in day-care by non-pharmaceutical interventions: a narrative review. Front Public Health 2024; 12:1332078. [PMID: 38420031 PMCID: PMC10899481 DOI: 10.3389/fpubh.2024.1332078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 02/02/2024] [Indexed: 03/02/2024] Open
Abstract
Objective Children who start in day-care have 2-4 times as many respiratory infections compared to children who are cared for at home, and day-care staff are among the employees with the highest absenteeism. The extensive new knowledge that has been generated in the COVID-19 era should be used in the prevention measures we prioritize. The purpose of this narrative review is to answer the questions: Which respiratory viruses are the most significant in day-care centers and similar indoor environments? What do we know about the transmission route of these viruses? What evidence is there for the effectiveness of different non-pharmaceutical prevention measures? Design Literature searches with different terms related to respiratory infections in humans, mitigation strategies, viral transmission mechanisms, and with special focus on day-care, kindergarten or child nurseries, were conducted in PubMed database and Web of Science. Searches with each of the main viruses in combination with transmission, infectivity, and infectious spread were conducted separately supplemented through the references of articles that were retrieved. Results Five viruses were found to be responsible for ≈95% of respiratory infections: rhinovirus, (RV), influenza virus (IV), respiratory syncytial virus (RSV), coronavirus (CoV), and adenovirus (AdV). Novel research, emerged during the COVID-19 pandemic, suggests that most respiratory viruses are primarily transmitted in an airborne manner carried by aerosols (microdroplets). Conclusion Since airborne transmission is dominant for the most common respiratory viruses, the most important preventive measures consist of better indoor air quality that reduces viral concentrations and viability by appropriate ventilation strategies. Furthermore, control of the relative humidity and temperature, which ensures optimal respiratory functionality and, together with low resident density (or mask use) and increased time outdoors, can reduce the occurrence of respiratory infections.
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Affiliation(s)
- Lars Andrup
- The National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Karen A Krogfelt
- Department of Science and Environment, Molecular and Medical Biology, PandemiX Center, Roskilde University, Roskilde, Denmark
| | - Lene Stephansen
- Gladsaxe Municipality, Social and Health Department, Gladsaxe, Denmark
| | | | | | - Peder Wolkoff
- The National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Anne Mette Madsen
- The National Research Centre for the Working Environment, Copenhagen, Denmark
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Zwitserloot AM, Verhoog FA, van den Berge M, Gappa M, Oosterom HW, Willemse BWM, Koppelman GH. Comparison of particles in exhaled air and multiple breath washout for assessment of small airway function in children with cystic fibrosis. Pediatr Pulmonol 2024. [PMID: 38179886 DOI: 10.1002/ppul.26847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 12/20/2023] [Accepted: 12/23/2023] [Indexed: 01/06/2024]
Abstract
BACKGROUND The introduction of modulator therapy for cystic fibrosis (CF) has led to an increased interest in the detection of small airway disease (SAD) as sensitive marker of treatment response. The particles in exhaled air (PExA) method, which records exhaled particle mass (PEx ng/L) and number (PExNR), detects SAD in adult patients. Our primary aim was to investigate if PExA outcomes in children with CF are different when compared to controls and associated with more severe disease. Secondary aims were to assess feasibility and repeatability of PExA in children with CF and to correlate PExA to multiple breath nitrogen washout (MBNW) as an established marker of SAD. METHODS Thirteen healthy children (HC), 17 children with CF with normal lung function (CF-N) (FEV1 z-score ≥ -1.64) and six with airway obstruction (CF-AO) (FEV1 z-score < -1.64) between 8 and 18 years performed MBNW followed by PExA and spirometry. Children with CF repeated the measurements after 3 months. RESULTS PEx ng/L and PExNR/L per liter of exhaled breath were similar between the three groups. The lung clearance index (LCI) was significantly higher in both CF-N and CF-AO compared to HC. All participants, except one, were able to perform PExA. Coefficient of variation for PEx ng/l was (median) 0.38, range 0-1.25 and PExNR/l 0.38, 0-1.09. Correlation between LCI and PEx ng/l was low, rs 0.32 (p = .07). CONCLUSION PExA is feasible in children. In contrast to LCI, PExA did not differentiate healthy children from children with CF suggesting it to be a less sensitive tool to detect SAD.
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Affiliation(s)
- Annelies M Zwitserloot
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Department of Pediatric Pulmonology and Pediatric Allergy, Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
| | - Frank A Verhoog
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Department of Pediatric Pulmonology and Pediatric Allergy, Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
| | - Maarten van den Berge
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Department of Pulmonary Diseases, Groningen, The Netherlands
| | - Monika Gappa
- Evangelisches Krankenhaus Düsseldorf, Children's Hospital, Düsseldorf, Germany
| | - Helma W Oosterom
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Department of Pediatric Pulmonology and Pediatric Allergy, Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Department of Pulmonary Diseases, Groningen, The Netherlands
| | - Brigitte W M Willemse
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Department of Pediatric Pulmonology and Pediatric Allergy, Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
| | - Gerard H Koppelman
- University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Department of Pediatric Pulmonology and Pediatric Allergy, Groningen, The Netherlands
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
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Gutmann D, Scheuch G, Lehmkühler T, Herrlich LS, Landeis A, Hutter M, Stephan C, Vehreschild M, Khodamoradi Y, Gossmann AK, King F, Weis F, Weiss M, Rabenau HF, Graf J, Donath H, Schubert R, Zielen S. Aerosol measurement identifies SARS-CoV 2 PCR positive adults compared with healthy controls. ENVIRONMENTAL RESEARCH 2023; 216:114417. [PMID: 36162469 PMCID: PMC9507996 DOI: 10.1016/j.envres.2022.114417] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 07/24/2022] [Accepted: 09/20/2022] [Indexed: 05/04/2023]
Abstract
BACKGROUND SARS-CoV-2 is spread primarily through droplets and aerosols. Exhaled aerosols are generated in the upper airways through shear stress and in the lung periphery by 'reopening of collapsed airways'. Aerosol measuring may detect highly contagious individuals ("super spreaders or super-emitters") and discriminate between SARS-CoV-2 infected and non-infected individuals. This is the first study comparing exhaled aerosols in SARS-CoV-2 infected individuals and healthy controls. DESIGN A prospective observational cohort study in 288 adults, comprising 64 patients testing positive by SARS CoV-2 PCR before enrollment, and 224 healthy adults testing negative (matched control sample) at the University Hospital Frankfurt, Germany, from February to June 2021. Study objective was to evaluate the concentration of exhaled aerosols during physiologic breathing in SARS-CoV-2 PCR-positive and -negative subjects. Secondary outcome measures included correlation of aerosol concentration to SARS-CoV-2 PCR results, change in aerosol concentration due to confounders, and correlation between clinical symptoms and aerosol. RESULTS There was a highly significant difference in respiratory aerosol concentrations between SARS-CoV-2 PCR-positive (median 1490.5/L) and -negative subjects (median 252.0/L; p < 0.0001). There were no significant differences due to age, sex, smoking status, or body mass index. ROC analysis showed an AUC of 0.8918. CONCLUSIONS Measurements of respiratory aerosols were significantly elevated in SARS-CoV-2 positive individuals, which helps to understand the spread and course of respiratory viral infections, as well as the detection of highly infectious individuals.
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Affiliation(s)
- Desireé Gutmann
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany.
| | - Gerhard Scheuch
- GS Bio-Inhalation GmbH, Headquarters & Logistics, Gemuenden, Germany
| | - Timon Lehmkühler
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Laura-Sabine Herrlich
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Anton Landeis
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Martin Hutter
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Christoph Stephan
- Department of Internal Medicine, Infectious Diseases, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Maria Vehreschild
- Department of Internal Medicine, Infectious Diseases, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Yascha Khodamoradi
- Department of Internal Medicine, Infectious Diseases, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Ann-Kathrin Gossmann
- Palas GmbH, Partikel- und Lasermesstechnik, Greschbachstrasse 3b; 76229, Karlsruhe, Germany
| | - Florian King
- Palas GmbH, Partikel- und Lasermesstechnik, Greschbachstrasse 3b; 76229, Karlsruhe, Germany
| | - Frederik Weis
- Palas GmbH, Partikel- und Lasermesstechnik, Greschbachstrasse 3b; 76229, Karlsruhe, Germany
| | - Maximilian Weiss
- Palas GmbH, Partikel- und Lasermesstechnik, Greschbachstrasse 3b; 76229, Karlsruhe, Germany
| | - Holger F Rabenau
- Institute for Medical Virology, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Juergen Graf
- Medical Director, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Helena Donath
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Ralf Schubert
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
| | - Stefan Zielen
- Department for Children and Adolescents, Division of Allergology, Pulmonology and Cystic Fibrosis, University Hospital Frankfurt, Goethe University, 60590, Frankfurt, Germany
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Penner T, Berger S, Niessner J, Dittler A. Generation, characterization, and comparison of human exhaled and technical aerosols for the evaluation of different air-purifying technologies against infectious aerosols. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2022; 19:646-662. [PMID: 36122386 DOI: 10.1080/15459624.2022.2125520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In light of the COVID-19 pandemic, the importance of protective measures against infectious aerosols has drastically increased, as the transmission of diseases via airborne particles is impacting many aspects of everyday life. The protective measures against such infections are determinant in the operation of schools and kindergartens, hygiene in hospitals and medical facilities, in offices, administrative and production facilities, hotels, and the event industry, among others. To test these protective measures, suitable test aerosols and processes are needed. These aerosols ought to be similar to aerosols exhaled by humans as those carry the pathogens and thus need to be removed from the air or inactivated. The exhaled aerosols of several healthy test subjects were characterized by their particle concentration and size distribution. In previous studies, it was found that exhaled particle concentration varies significantly from subject to subject and most of the particles can be found in the submicron size range. Aerosols technically generated through nebulization were emitted by the generators in particle concentrations several orders of magnitude higher than those exhaled by humans, independent of the aerosol generation method and nebulized fluid. The particle size distribution generated by the two nebulizers used, however, was quite similar to the measured size distributions of the human aerosols, with most of the particles below 1 µm in size. Consequently, the used aerosol generators are not suitable to mimic single individuals as active aerosol sources, but rather to provide a sufficient amount of aerosol similar to human aerosols in size distribution, which can be used in the testing of air purification technologies.
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Affiliation(s)
- Thomas Penner
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Simon Berger
- Institute for Flow in Additively Manufactured Porous Media, Heilbronn University of Applied Sciences, Heilbronn, Germany
| | - Jennifer Niessner
- Institute for Flow in Additively Manufactured Porous Media, Heilbronn University of Applied Sciences, Heilbronn, Germany
| | - Achim Dittler
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany
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Morawska L, Buonanno G, Mikszewski A, Stabile L. The physics of respiratory particle generation, fate in the air, and inhalation. NATURE REVIEWS. PHYSICS 2022; 4:723-734. [PMID: 36065441 PMCID: PMC9430019 DOI: 10.1038/s42254-022-00506-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/03/2022] [Indexed: 05/31/2023]
Abstract
Given that breathing is one of the most fundamental physiological functions, there is an urgent need to broaden our understanding of the fluid dynamics that governs it. There would be many benefits from doing so, including a better assessment of respiratory health, a basis for more precise delivery of pharmaceutical drugs for treatment, and the understanding and potential minimization of respiratory infection transmission. We review the physics of particle generation in the respiratory tract, the fate of these particles in the air on exhalation and the physics of particle inhalation. The main focus is on evidence from experimental studies. We conclude that although there is qualitative understanding of the generation of particles in the respiratory tract, a basic quantitative knowledge of the characteristics of the particles emitted during respiratory activities and their fate after emission, and a theoretical understanding of particle deposition during inhalation, nevertheless the general understanding of the entire process is rudimentary, and many open questions remain.
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Affiliation(s)
- Lidia Morawska
- Queensland University of Technology, International Laboratory for Air Quality & Health (ILAQH), Brisbane, Queensland Australia
- Global Centre for Clean Air Research, Department of Civil and Environmental Engineering, University of Surrey, Guildford, UK
| | - Giorgio Buonanno
- Queensland University of Technology, International Laboratory for Air Quality & Health (ILAQH), Brisbane, Queensland Australia
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, Italy
| | - Alex Mikszewski
- Queensland University of Technology, International Laboratory for Air Quality & Health (ILAQH), Brisbane, Queensland Australia
| | - Luca Stabile
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, Italy
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Aerosol emissions from wind instruments: effects of performer age, sex, sound pressure level, and bell covers. Sci Rep 2022; 12:11303. [PMID: 35788635 PMCID: PMC9252563 DOI: 10.1038/s41598-022-15530-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 06/24/2022] [Indexed: 12/30/2022] Open
Abstract
Aerosol emissions from wind instruments are a suspected route of transmission for airborne infectious diseases, such as SARS-CoV-2. We evaluated aerosol number emissions (from 0.25 to 35.15 μm) from 81 volunteer performers of both sexes and varied age (12 to 63 years) while playing wind instruments (bassoon, clarinet, flute, French horn, oboe, piccolo, saxophone, trombone, trumpet, and tuba) or singing. Measured emissions spanned more than two orders of magnitude, ranging in rate from < 8 to 1,815 particles s-1, with brass instruments, on average, producing 191% (95% CI 81-367%) more aerosol than woodwinds. Being male was associated with a 70% increase in emissions (vs. female; 95% CI 9-166%). Each 1 dBA increase in sound pressure level was associated with a 28% increase (95% CI 10-40%) in emissions from brass instruments; sound pressure level was not associated with woodwind emissions. Age was not a significant predictor of emissions. The use of bell covers reduced aerosol emissions from three brass instruments tested (trombone, tuba, and trumpet), with average reductions ranging from 53 to 73%, but not for the two woodwind instruments tested (oboe and clarinet). Results from this work can facilitate infectious disease risk management for the performing arts.
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Held A, Dellweg D, Köhler D, Pfaender S, Scheuch G, Schumacher S, Steinmann E, Weingartner E, Weinzierl B, Asbach C. [Interdisciplinary Perspectives on the Role of Aerosol Transmission in SARS-CoV-2 Infections]. DAS GESUNDHEITSWESEN 2022; 84:566-574. [PMID: 35835094 DOI: 10.1055/a-1808-0086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The relevance of aerosols for the transmission of the Severe Acute Respiratory Syndrome Coronavirus Type 2 (SARS-CoV-2) is still debated. However, over time, in addition to distancing and hygiene rules, aerosol physics-based measures such as wearing face masks and ventilating indoor spaces were found to be efficient in reducing infections. In an interdisciplinary workshop "Aerosol & SARS-CoV-2" of the Association for Aerosol Research (GAeF) in cooperation with the German Society for Pneumology and Respiratory Medicine (DGP), the Professional Association of General Air Technology of the VDMA, the German Society for Virology (GfV), the Health Technology Society (GG) and the International Society for Aerosols in Medicine (ISAM) under the auspices of the Robert Koch Institute (RKI) in March 2021, the need for research and coordination on this topic was addressed. Fundamental findings from the various disciplines as well as interdisciplinary perspectives on aerosol transmission of SARS-CoV-2 and infection mitigation measures are summarized here. Finally, open research questions and needs are presented.
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Affiliation(s)
- Andreas Held
- FG Umweltchemie und Luftreinhaltung, Technische Universität Berlin, Berlin, Germany
| | - Dominic Dellweg
- Pneumologie, Fachkrankenhaus Kloster Grafschaft GmbH, Schmallenberg, Germany
| | | | - Stephanie Pfaender
- Abteilung für Molekulare und Medizinische Virologie, Ruhr-Universität Bochum, Bochum, Germany
| | | | - Stefan Schumacher
- Bereich Luftreinhaltung und Filtration, Institut für Energie- und Umwelttechnik e.V. (IUTA), Duisburg, Germany
| | - Eike Steinmann
- Abteilung für Molekulare und Medizinische Virologie, Ruhr-Universität Bochum, Bochum, Germany
| | - Ernest Weingartner
- Fachgruppe Aerosolmesstechnik, Fachhochschule Nordwestschweiz FHNW, Windisch, Switzerland
| | | | - Christof Asbach
- Bereich Luftreinhaltung und Filtration, Institut für Energie- und Umwelttechnik e.V. (IUTA), Duisburg, Germany
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Buonanno G, Robotto A, Brizio E, Morawska L, Civra A, Corino F, Lembo D, Ficco G, Stabile L. Link between SARS-CoV-2 emissions and airborne concentrations: Closing the gap in understanding. JOURNAL OF HAZARDOUS MATERIALS 2022; 428:128279. [PMID: 35063838 PMCID: PMC8760841 DOI: 10.1016/j.jhazmat.2022.128279] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 05/03/2023]
Abstract
The airborne transmission of SARS-CoV-2 remains surprisingly controversial; indeed, health and regulatory authorities still require direct proof of this mode of transmission. To close this gap, we measured the viral load of SARS-CoV-2 of an infected subject in a hospital room (through an oral and nasopharyngeal swab), as well as the airborne SARS-CoV-2 concentration in the room resulting from the person breathing and speaking. Moreover, we simulated the same scenarios to estimate the concentration of RNA copies in the air through a novel theoretical approach and conducted a comparative analysis between experimental and theoretical results. Results showed that for an infected subject's viral load ranging between 2.4 × 106 and 5.5 × 106 RNA copies mL-1, the corresponding airborne SARS-CoV-2 concentration was below the minimum detection threshold when the person was breathing, and 16.1 (expanded uncertainty of 32.8) RNA copies m-3 when speaking. The application of the predictive approach provided concentrations metrologically compatible with the available experimental data (i.e. for speaking activity). Thus, the study presented significant evidence to close the gap in understanding airborne transmission, given that the airborne SARS-CoV-2 concentration was shown to be directly related to the SARS-CoV-2 emitted. Moreover, the theoretical analysis was shown to be able to quantitatively link the airborne concentration to the emission.
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Affiliation(s)
- G Buonanno
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy; International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Qld, Australia; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - A Robotto
- Environmental Protection Agency of Piedmont (ARPA Piemonte), Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - E Brizio
- Environmental Protection Agency of Piedmont (ARPA Piemonte), Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - L Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Qld, Australia; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - A Civra
- Dept. of Clinical and Biological Science, Azienda Ospedaliero-Universitaria San Luigi Gonzaga, University of Turin, Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - F Corino
- Environmental Protection Agency of Piedmont (ARPA Piemonte), Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - D Lembo
- Dept. of Clinical and Biological Science, Azienda Ospedaliero-Universitaria San Luigi Gonzaga, University of Turin, Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - G Ficco
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy
| | - L Stabile
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy; Infectious Diseases Unit, Department of Medical Sciences, Amedeo di Savoia Hospital, University of Turin, Torino, Italy.
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11
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Ljungkvist G, Tinnerberg H, Löndahl J, Klang T, Viklund E, Kim JL, Schiöler L, Forsgard N, Olin AC. Exploring a new method for the assessment of metal exposure by analysis of exhaled breath of welders. Int Arch Occup Environ Health 2022; 95:1255-1265. [PMID: 35066624 PMCID: PMC9273541 DOI: 10.1007/s00420-022-01833-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 01/06/2022] [Indexed: 12/04/2022]
Abstract
Purpose Air monitoring has been the accepted exposure assessment of toxic metals from, e.g., welding, but a method characterizing the actual dose delivered to the lungs would be preferable. Sampling of particles in exhaled breath can be used for the biomonitoring of both endogenous biomarkers and markers of exposure. We have explored a new method for the sampling of metals in exhaled breath from the small airways in a study on welders. Methods Our method for particle sampling, Particles in Exhaled Air (PExA®), is based on particle counting and inertial impaction. We applied it on 19 stainless steel welders before and after a workday. In parallel, air monitoring of chromium, manganese and nickel was performed as well as blood sampling after work. Results Despite substantial exposure to welding fumes, we were unable to show any significant change in the metal content of exhaled particles after, compared with before, exposure. However, the significance might be obscured by a substantial analytical background noise, due to metal background in the sampling media and possible contamination during sampling, as an increase in the median metal contents were indicated. Conclusions If efforts to reduce background and contamination are successful, the PExA® method could be an important tool in the investigations of metals in exhaled breath, as the method collects particles from the small airways in contrast to other methods. In this paper, we discuss the discrepancy between our findings and results from studies, using the exhaled breath condensate (EBC) methodology.
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Affiliation(s)
- Göran Ljungkvist
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden.
| | - Håkan Tinnerberg
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden
| | - Jakob Löndahl
- Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Faculty of Engineering, Lund University, Lund, Sweden
| | - Therese Klang
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden
| | - Emilia Viklund
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden
| | - Jeong-Lim Kim
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden
| | - Linus Schiöler
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden
| | | | - Anna-Carin Olin
- Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Box 414, 405 30, Gothenburg, Sweden
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Viklund E, Kokelj S, Larsson P, Nordén R, Andersson M, Beck O, Westin J, Olin AC. Severe acute respiratory syndrome coronavirus 2 can be detected in exhaled aerosol sampled during a few minutes of breathing or coughing. Influenza Other Respir Viruses 2022; 16:402-410. [PMID: 35037404 PMCID: PMC8983906 DOI: 10.1111/irv.12964] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/22/2021] [Accepted: 01/04/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The knowledge on the concentration of viral particles in exhaled breath is limited. The aim of this study was to explore if severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be detected in aerosol from subjects with the coronavirus disease 2019 (COVID-19) during various types of breathing and coughing and how infection with SARS-CoV-2 may influence the number and size of exhaled aerosol particles. METHODS We counted and collected endogenous particles in exhaled breath in subjects with COVID-19 disease by two different impaction-based methods, during 20 normal breaths, 10 airway opening breaths, and three coughs, respectively. Breath samples were analyzed with reverse transcription real-time polymerase chain reaction (RT-PCR). RESULTS Detection of RNA in aerosol was possible in 10 out of 25 subjects. Presence of virus RNA in aerosol was mainly found in cough samples (n = 8), but also in airway opening breaths (n = 3) and in normal breaths (n = 4), with no overlap between the methods. No association between viral load in aerosol and number exhaled particles <5 μm was found. Subjects with COVID-19 exhaled less particles than healthy controls during normal breathing and airway opening breaths (all P < 0.05), but not during cough. CONCLUSION SARS-CoV-2 RNA can be detected in exhaled aerosol, sampled during a limited number of breathing and coughing procedures. Detection in aerosol seemed independent of viral load in the upper airway swab as well as of the exhaled number of particles. The infectious potential of the amount of virus detected in aerosol needs to be further explored.
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Affiliation(s)
- Emilia Viklund
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Spela Kokelj
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Per Larsson
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Rickard Nordén
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Clinical Microbiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Maria Andersson
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Olof Beck
- Department of Clinical Neuroscience, Karolinska Institute, Solna, Sweden
| | - Johan Westin
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Clinical Microbiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Anna-Carin Olin
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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13
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Wilson NM, Marks GB, Eckhardt A, Clarke AM, Young FP, Garden FL, Stewart W, Cook TM, Tovey ER. The effect of respiratory activity, non-invasive respiratory support and facemasks on aerosol generation and its relevance to COVID-19. Anaesthesia 2021; 76:1465-1474. [PMID: 33784793 PMCID: PMC8250912 DOI: 10.1111/anae.15475] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2021] [Indexed: 12/11/2022]
Abstract
Respirable aerosols (< 5 µm in diameter) present a high risk of SARS‐CoV‐2 transmission. Guidelines recommend using aerosol precautions during aerosol‐generating procedures, and droplet (> 5 µm) precautions at other times. However, emerging evidence indicates respiratory activities may be a more important source of aerosols than clinical procedures such as tracheal intubation. We aimed to measure the size, total number and volume of all human aerosols exhaled during respiratory activities and therapies. We used a novel chamber with an optical particle counter sampling at 100 l.min‐1 to count and size‐fractionate close to all exhaled particles (0.5–25 µm). We compared emissions from ten healthy subjects during six respiratory activities (quiet breathing; talking; shouting; forced expiratory manoeuvres; exercise; and coughing) with three respiratory therapies (high‐flow nasal oxygen and single or dual circuit non‐invasive positive pressure ventilation). Activities were repeated while wearing facemasks. When compared with quiet breathing, exertional respiratory activities increased particle counts 34.6‐fold during talking and 370.8‐fold during coughing (p < 0.001). High‐flow nasal oxygen 60 at l.min‐1 increased particle counts 2.3‐fold (p = 0.031) during quiet breathing. Single and dual circuit non‐invasive respiratory therapy at 25/10 cm.H2O with quiet breathing increased counts by 2.6‐fold and 7.8‐fold, respectively (both p < 0.001). During exertional activities, respiratory therapies and facemasks reduced emissions compared with activities alone. Respiratory activities (including exertional breathing and coughing) which mimic respiratory patterns during illness generate substantially more aerosols than non‐invasive respiratory therapies, which conversely can reduce total emissions. We argue the risk of aerosol exposure is underappreciated and warrants widespread, targeted interventions.
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Affiliation(s)
- N M Wilson
- Department of Intensive Care Medicine, Prince of Wales Hospital, Sydney, Australia.,Department of Anaesthesia, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - G B Marks
- Department of Respiratory Medicine, University of New South Wales, Sydney, Australia
| | - A Eckhardt
- Department of Intensive Care Medicine, Prince of Wales Hospital, Sydney, Australia
| | - A M Clarke
- Department of Intensive Care, Royal Prince Alfred Hospital, Sydney, Australia
| | - F P Young
- Department of Intensive Care Medicine, Prince of Wales Hospital, Sydney, Australia
| | - F L Garden
- University of New South Wales, Sydney, Australia
| | - W Stewart
- Department of Intensive Care Medicine, Prince of Wales Hospital, Sydney, Australia
| | - T M Cook
- Department of Anaesthesia and Intensive Care Medicine, Royal United Hospitals NHS Trust, Bath, UK.,Bristol Medical School, University of Bristol, UK
| | - E R Tovey
- Woolcock Institute of Medical Research, University of Sydney, Australia
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14
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Hussain-Alkhateeb L, Bake B, Holm M, Emilsson Ö, Mirgorodskaya E, Olin AC. Novel non-invasive particles in exhaled air method to explore the lining fluid of small airways-a European population-based cohort study. BMJ Open Respir Res 2021; 8:8/1/e000804. [PMID: 33402401 PMCID: PMC7786806 DOI: 10.1136/bmjresp-2020-000804] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/25/2020] [Accepted: 11/27/2020] [Indexed: 01/18/2023] Open
Abstract
INTRODUCTION Respiratory tract lining fluid of small airways mainly consists of surfactant that can be investigated by collection of the particles of exhaled aerosol (PExA) method. This offers an exciting prospect to monitor small airway pathology, including subjects with asthma and smokers. AIM To explore the influence of anthropometric factors and gender on phospholipids, surfactant protein A (SP-A) and albumin of the lining fluid of small airwaysand to examine the association with asthma and smoking. Furthermore, to examine if the surfactant components can predict lung function in terms of spirometry variables. METHOD This study employs the population-based cohort of the European Community Respiratory Health Survey III, including participants from Gothenburg city, Sweden (n=200). The PExA method enabled quantitative description and analytical analysis of phospholipids, SP-A and albumin of the lining fluid of small airways. RESULTS Age was a significant predictor of the phospholipids. The components PC14:0/16:0, PC16:0/18:2 (PC, phosphatidylcholine) and SP-A were higher among subjects with asthma, whereas albumin was lower. Among smokers, there were higher levels particularly of di-palmitoyl-di-phosphatidyl-choline compared with non-smokers. Most phospholipids significantly predicted the spirometry variables. CONCLUSION This non-invasive PExA method appears to have great potential to explore the role of lipids and proteins of surfactant in respiratory disease.
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Affiliation(s)
- Laith Hussain-Alkhateeb
- Public Health and Community Medicine, University of Gothenburg Sahlgrenska Academy, Goteborg, Sweden
| | - Björn Bake
- Department of Respiratory Medicine and Allergology, Insitute of Medicine, Gothenburg, Sweden
| | - Mathias Holm
- Public Health and Community Medicine, University of Gothenburg Sahlgrenska Academy, Goteborg, Sweden
| | - Össur Emilsson
- Department of Medical Sciences, Respiratory, allergy and sleep research, Uppsala University, Uppsala, Sweden
| | | | - Anna-Carin Olin
- Public Health and Community Medicine, University of Gothenburg Sahlgrenska Academy, Goteborg, Sweden
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15
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Scheuch G. Breathing Is Enough: For the Spread of Influenza Virus and SARS-CoV-2 by Breathing Only. J Aerosol Med Pulm Drug Deliv 2020; 33:230-234. [PMID: 32552296 PMCID: PMC7406993 DOI: 10.1089/jamp.2020.1616] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background: The transmission of respiratory viruses such as influenza and corona viruses from one person to another is still not fully understood. Methods: A literature search showed that there is a strong scientific rationale and evidence that viruses are very efficiently spread through aerosols by the patient's breathing only. It is not necessary for the patient to cough or sneeze. Results: The exhaled aerosol particles are generated by normal breathing in the deep lung through reopening of collapsed small airways during inspiration. These mucus/surfactant aerosols (size range between 0.2 and 0.6 μm) can transport viruses out of the lungs of patients and be present in the room air for hours. Conclusion: These aerosol particles are difficult to filter out of the air; because of their physical properties, new strategies must be developed to protect people from these virus aerosols.
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Affiliation(s)
- Gerhard Scheuch
- GS Bio-Inhalation GmbH, Headquarters & Logistics, Gemuenden, Germany
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16
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Kokelj S, Kim JL, Andersson M, Runström Eden G, Bake B, Olin AC. Intra-individual variation of particles in exhaled air and of the contents of Surfactant protein A and albumin. PLoS One 2020; 15:e0227980. [PMID: 31978133 PMCID: PMC6980535 DOI: 10.1371/journal.pone.0227980] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/04/2020] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Particles in exhaled air (PEx) provide samples of respiratory tract lining fluid from small airways containing, for example, Surfactant protein A (SP-A) and albumin, potential biomarkers of small airway disease. We hypothesized that there are differences between morning, noon, and afternoon measurements and that the variability of repeated measurements is larger between days than within days. METHODS PEx was obtained in sixteen healthy non-smoking adults on 11 occasions, within one day and between days. SP-A and albumin were quantified by ELISA. The coefficient of repeatability (CR), intraclass correlation coefficient (ICC), and coefficient of variation (CV) were used to assess the variation of repeated measurements. RESULTS SP-A and albumin increased significantly from morning towards the noon and afternoon by 13% and 25% on average, respectively, whereas PEx number concentration and particle mean mass did not differ significantly between the morning, noon and afternoon. Between-day CRs were not larger than within-day CRs. CONCLUSIONS Time of the day influences the contents of SP-A and albumin in exhaled particles. The variation of repeated measurements was rather high but was not influenced by the time intervals between measurements.
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Affiliation(s)
- Spela Kokelj
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- * E-mail:
| | - Jeong-Lim Kim
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Marianne Andersson
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Gunilla Runström Eden
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Björn Bake
- Unit of Respiratory Medicine and Allergy, Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anna-Carin Olin
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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17
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Patterson B, Wood R. Is cough really necessary for TB transmission? Tuberculosis (Edinb) 2019; 117:31-35. [PMID: 31378265 PMCID: PMC6688829 DOI: 10.1016/j.tube.2019.05.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/06/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
Cough has long been implicated in the production of infectious aerosol leading to transmission of tuberculosis (TB). However, prevalence studies frequently identify radiographic evidence of TB in subclinical individuals in the absence of reported coughing. Elucidating the role of cough in transmission depends on understanding the physical process of aerosolizing and expelling mycobacterium tuberculosis (Mtb) bacilli. In the last decade, human aerosol studies have progressed with improved precision of particle detection and greater sophistication of experimental protocols. Combining principles of respiratory physiology, the site and mechanism of aerosolization of respiratory lining fluids during phases of the respiratory cycle has been investigated in detail. Additionally, recent success in the direct detection of naturally generated Mtb aerosols has allowed more detailed characterization in terms of their rate of production and size distribution. We propose that TB transmission depends on the coincidence of the site of aerosol generation with the presence of Mtb bacilli. This review will examine the evidence for site of aerosol production during cough and respiratory activities in conjunction with the characteristics of detectable Mtb aerosols and locations of tuberculosis infection. Furthermore, we propose respiratory activities that are likely to optimise aerosol sampling for investigation of transmission.
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Affiliation(s)
- Benjamin Patterson
- University of Amsterdam, Amsterdam Institute for Global Health and Development, Amsterdam, the Netherlands; Desmond Tutu HIV Centre, IDM, University of Cape Town, Cape Town, South Africa.
| | - Robin Wood
- Desmond Tutu HIV Centre, IDM, University of Cape Town, Cape Town, South Africa; Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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18
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Bake B, Larsson P, Ljungkvist G, Ljungström E, Olin AC. Exhaled particles and small airways. Respir Res 2019; 20:8. [PMID: 30634967 PMCID: PMC6330423 DOI: 10.1186/s12931-019-0970-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 01/01/2019] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Originally, studies on exhaled droplets explored properties of airborne transmission of infectious diseases. More recently, the interest focuses on properties of exhaled droplets as biomarkers, enabled by the development of technical equipment and methods for chemical analysis. Because exhaled droplets contain nonvolatile substances, particles is the physical designation. This review aims to outline the development in the area of exhaled particles, particularly regarding biomarkers and the connection with small airways, i e airways with an internal diameter < 2 mm. MAIN BODY Generation mechanisms, sites of origin, number concentrations of exhaled particles and the content of nonvolatile substances are studied. Exhaled particles range in diameter from 0.01 and 1000 μm depending on generation mechanism and site of origin. Airway reopening is one scientifically substantiated particle generation mechanism. During deep expirations, small airways close and the reopening process produces minute particles. When exhaled, these particles have a diameter of < 4 μm. A size discriminating sampling of particles < 4 μm and determination of the size distribution, allows exhaled particle mass to be estimated. The median mass is represented by particles in the size range of 0.7 to 1.0 μm. Half an hour of repeated deep expirations result in samples in the order of nanogram to microgram. The source of these samples is the respiratory tract ling fluid of small airways and consists of lipids and proteins, similarly to surfactant. Early clinical studies of e g chronic obstructive pulmonary disease and asthma, reported altered particle formation and particle composition. CONCLUSION The physical properties and content of exhaled particles generated by the airway reopening mechanism offers an exciting noninvasive way to obtain samples from the respiratory tract lining fluid of small airways. The biomarker potential is only at the beginning to be explored.
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Affiliation(s)
- B. Bake
- Unit of Respiratory Medicine and Allergy, Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - P. Larsson
- Unit of Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - G. Ljungkvist
- Unit of Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - E. Ljungström
- Atmospheric Science, Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - A-C Olin
- Unit of Occupational and Environmental Medicine, Department of Public Health and Community Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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19
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Seferaj S, Ullah S, Tinglev Å, Carlsson S, Winberg J, Stambeck P, Beck O. Evaluation of a new simple collection device for sampling of microparticles in exhaled breath. J Breath Res 2018; 12:036005. [PMID: 29440627 DOI: 10.1088/1752-7163/aaaf24] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The microparticle fraction of exhaled breath is of interest for developing clinical biomarkers. Exhaled particles may contain non-volatile components from all parts of the airway system, formed during normal breathing. This study aimed to evaluate a new, simple sampling device, based on impaction, for collecting microparticles from exhaled breath. Performance of the new device was compared with that of the existing SensAbues membrane filter device. The analytical work used liquid chromatography-tandem mass spectrometry methods. The new device collected three subsamples and these were separately analysed from eight individuals. No difference was observed between the centre position (0.91 ng/sample) and the side positions (1.01 ng/sample) using major phosphatidylcholine (PC) 16:0/16:0 as the analyte. Exhaled breath was collected from eight patients on methadone maintenance treatment. The intra-individual variability in measured methadone concentration between the three collectors was 8.7%. In another experiment using patients on methadone maintenance treatment, the sampling efficiency was compared with an established filter device. Compared to the existing device, the efficiency of the new device was 121% greater for methadone and 1450% greater for DPPC. The data from lipid analysis also indicated that a larger fraction of the collected material was from the distal parts. Finally, a study using an optical particle counter indicated that the device preferentially collects the larger particle fraction. In conclusion, this study demonstrates the usefulness of the new device for collecting non-volatile components from exhaled breath. The performance of the device was superior to the filter device in several aspects.
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Affiliation(s)
- Sabina Seferaj
- Karolinska University Laboratory, Department of Clinical Pharmacology, Stockholm, Sweden
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