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Longest AK, Rockey NC, Lakdawala SS, Marr LC. Review of factors affecting virus inactivation in aerosols and droplets. J R Soc Interface 2024; 21:18. [PMID: 38920060 DOI: 10.1098/rsif.2024.0018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/25/2024] [Indexed: 06/27/2024] Open
Abstract
The inactivation of viruses in aerosol particles (aerosols) and droplets depends on many factors, but the precise mechanisms of inactivation are not known. The system involves complex physical and biochemical interactions. We reviewed the literature to establish current knowledge about these mechanisms and identify knowledge gaps. We identified 168 relevant papers and grouped results by the following factors: virus type and structure, aerosol or droplet size, temperature, relative humidity (RH) and evaporation, chemical composition of the aerosol or droplet, pH and atmospheric composition. These factors influence the dynamic microenvironment surrounding a virion and thus may affect its inactivation. Results indicate that viruses experience biphasic decay as the carrier aerosols or droplets undergo evaporation and equilibrate with the surrounding air, and their final physical state (liquid, semi-solid or solid) depends on RH. Virus stability, RH and temperature are interrelated, but the effects of RH are multifaceted and still not completely understood. Studies on the impact of pH and atmospheric composition on virus stability have raised new questions that require further exploration. The frequent practice of studying virus inactivation in large droplets and culture media may limit our understanding of inactivation mechanisms that are relevant for transmission, so we encourage the use of particles of physiologically relevant size and composition in future research.
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Affiliation(s)
- Alexandra K Longest
- Department of Civil and Environmental Engineering, Virginia Tech , Blacksburg, VA, USA
| | - Nicole C Rockey
- Department of Civil and Environmental Engineering, Duke University , Durham, NC, USA
| | - Seema S Lakdawala
- Department of Microbiology and Immunology, Emory University , Atlanta, GA, USA
| | - Linsey C Marr
- Department of Civil and Environmental Engineering, Virginia Tech , Blacksburg, VA, USA
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Suh IY, Huo ZY, Jung JH, Kang D, Lee DM, Kim YJ, Kim B, Jeon J, Zhao P, Shin J, Kim S, Kim SW. Highly efficient microbial inactivation enabled by tunneling charges injected through two-dimensional electronics. SCIENCE ADVANCES 2024; 10:eadl5067. [PMID: 38701201 PMCID: PMC11067992 DOI: 10.1126/sciadv.adl5067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 04/01/2024] [Indexed: 05/05/2024]
Abstract
Airborne pathogens retain prolonged infectious activity once attached to the indoor environment, posing a pervasive threat to public health. Conventional air filters suffer from ineffective inactivation of the physics-separated microorganisms, and the chemical-based antimicrobial materials face challenges of poor stability/efficiency and inefficient viral inactivation. We, therefore, developed a rapid, reliable antimicrobial method against the attached indoor bacteria/viruses using a large-scale tunneling charge-motivated disinfection device fabricated by directly dispersing monolayer graphene on insulators. Free charges can be stably immobilized under the monolayer graphene through the tunneling effect. The stored charges can motivate continuous electron loss of attached microorganisms for accelerated disinfection, overcoming the diffusion limitation of chemical disinfectants. Complete (>99.99%) and broad-spectrum disinfection was achieved <1 min of attachment to the scaled-up device (25 square centimeters), reliably for 72 hours at high temperature (60°C) and humidity (90%). This method can be readily applied to high-touch surfaces in indoor environments for pathogen control.
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Affiliation(s)
- In-Yong Suh
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Zheng-Yang Huo
- School of Environment and Natural Resources, Institute of Ecological Civilization, Renmin University of China, Beijing 100872, PR China
| | - Jae-Hwan Jung
- Thin Film Materials Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Republic of Korea
| | - Donghyeon Kang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Dong-Min Lee
- Department of Materials Science and Engineering, Center for Human-oriented Triboelectric Energy Harvesting, Yonsei University, Seoul 03722, Republic of Korea
| | - Young-Jun Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Bosung Kim
- Department of Materials Science and Engineering, Center for Human-oriented Triboelectric Energy Harvesting, Yonsei University, Seoul 03722, Republic of Korea
| | - Jinyoung Jeon
- Department of Materials Science and Engineering, Center for Human-oriented Triboelectric Energy Harvesting, Yonsei University, Seoul 03722, Republic of Korea
| | - Pin Zhao
- Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, PR China
| | - Jeonghune Shin
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Research and Development Center, SEMS CO., Ltd., Suwon 16229, Republic of Korea
| | - SeongMin Kim
- Department of Materials Science and Engineering, Center for Human-oriented Triboelectric Energy Harvesting, Yonsei University, Seoul 03722, Republic of Korea
| | - Sang-Woo Kim
- Department of Materials Science and Engineering, Center for Human-oriented Triboelectric Energy Harvesting, Yonsei University, Seoul 03722, Republic of Korea
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Huisman M, Digard P, Poon WCK, Titmuss S. Evaporation of Concentrated Polymer Solutions Is Insensitive to Relative Humidity. PHYSICAL REVIEW LETTERS 2023; 131:248102. [PMID: 38181132 DOI: 10.1103/physrevlett.131.248102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 06/12/2023] [Accepted: 10/24/2023] [Indexed: 01/07/2024]
Abstract
A recent theory suggests that the evaporation kinetics of macromolecular solutions is insensitive to the ambient relative humidity (RH) due to the formation of a "polarization layer" of solutes at the air-solution interface. We confirm this insensitivity up to RH≈80% in the evaporation of polyvinyl alcohol solutions from open-ended capillaries. To explain the observed drop in evaporation rate at higher RH, we need to invoke compressive stresses due to interfacial polymer gelation. Moreover, RH-insensitive evaporation sets in earlier than theory predicts, suggesting a further role for a gelled "skin." We discuss the relevance of these observations for respiratory virus transmission via aerosols.
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Affiliation(s)
- Max Huisman
- SUPA and School of Physics and Astronomy, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom
| | - Paul Digard
- Department of Infection and Immunity, The Roslin Institute, The University of Edinburgh, Easter Bush Campus, Edinburgh EH25 9RG, United Kingdom
| | - Wilson C K Poon
- SUPA and School of Physics and Astronomy, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom
| | - Simon Titmuss
- SUPA and School of Physics and Astronomy, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom
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Marco L, Cambien G, Garcia M, Broutin L, Cateau E, Lariviere A, Castel O, Thevenot S, Bousseau A. [Respiratory infections: Additional transmission-based precautions in healthcare facilities]. Rev Mal Respir 2023; 40:572-603. [PMID: 37365075 DOI: 10.1016/j.rmr.2023.05.001] [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: 09/29/2022] [Accepted: 05/04/2023] [Indexed: 06/28/2023]
Abstract
INTRODUCTION In health care, measures against cross-transmission of microorganisms are codified by standard precautions, and if necessary, they are supplemented by additional precautions. STATE OF THE ART Several factors impact transmission of microorganisms via the respiratory route: size and quantity of the emitted particles, environmental conditions, nature and pathogenicity of the microorganisms, and degree of host receptivity. While some microorganisms necessitate additional airborne or droplet precautions, others do not. PROSPECTS For most microorganisms, transmission patterns are well-understood and transmission-based precautions are well-established. For others, measures to prevent cross-transmission in healthcare facilities remain under discussion. CONCLUSIONS Standard precautions are essential to the prevention of microorganism transmission. Understanding of the modalities of microorganism transmission is essential to implementation of additional transmission-based precautions, particularly in view of opting for appropriate respiratory protection.
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Affiliation(s)
- L Marco
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - G Cambien
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France; Inserm CIC 1402, université de Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - M Garcia
- Département des agents infectieux, laboratoire de virologie et mycobactériologie, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France; Laboratoire inflammation, tissus épithéliaux et cytokines, EA 4331, université de Poitiers, 86021 Poitiers, France
| | - L Broutin
- Département des agents infectieux, laboratoire de bactériologie, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - E Cateau
- Laboratoire écologie et biologie des interactions, UMR CNRS 7267, université de Poitiers, 86021 Poitiers, France; Département des agents infectieux, laboratoire de parasitologie et mycologie médicale, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - A Lariviere
- Département des agents infectieux, laboratoire de virologie et mycobactériologie, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - O Castel
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France
| | - S Thevenot
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France; Inserm CIC 1402, université de Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - A Bousseau
- Unité d'hygiène hospitalière, département des agents infectieux, pôle BIOSPHARM, CHU de Poitiers, 86021 Poitiers, France.
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Duan JL, Ma JY, Sun XD, Liu XY, Wang Y, Du L, Xia PF, Yuan XZ. Bubbles Expand the Dissemination of Antibiotic Resistance in the Aquatic Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37379503 DOI: 10.1021/acs.est.3c02935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
Antibiotic resistance is a global health challenge, and the COVID-19 pandemic has amplified the urgency to understand its airborne transmission. The bursting of bubbles is a fundamental phenomenon in natural and industrial processes, with the potential to encapsulate or adsorb antibiotic-resistant bacteria (ARB). However, there is no evidence to date for bubble-mediated antibiotic resistance dissemination. Here, we show that bubbles can eject abundant bacteria to the air, form stable biofilms over the air-water interface, and provide opportunities for cell-cell contact that facilitates horizontal gene transfer at and over the air-liquid interface. The extracellular matrix (ECM) on bacteria can increase bubble attachment on biofilms, increase bubble lifetime, and, thus, produce abundant small droplets. We show through single-bubble probe atomic force microscopy and molecular dynamics simulations that hydrophobic interactions with polysaccharides control how the bubble interacts with the ECM. These results highlight the importance of bubbles and its physicochemical interaction with ECM in facilitating antibiotic resistance dissemination and fulfill the framework on antibiotic resistance dissemination.
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Affiliation(s)
- Jian-Lu Duan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Jing-Ya Ma
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xiao-Dong Sun
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xiao-Yu Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Yue Wang
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Lin Du
- Environment Research Institute, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Peng-Fei Xia
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xian-Zheng Yuan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
- Sino-French Research Institute for Ecology and Environment (ISFREE), Shandong University, Qingdao, Shandong 266237, P. R. China
- Weihai Research Institute of Industrial Technology, Shandong University, Weihai, Shandong 264209, P. R. China
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Moschovis PP, Lombay J, Rooney J, Schenkel SR, Singh D, Rezaei SJ, Salo N, Gong A, Yonker LM, Shah J, Hayden D, Hibberd PL, Demokritou P, Kinane TB. The effect of activity and face masks on exhaled particles in children. Pediatr Investig 2023; 7:75-85. [PMID: 37324601 PMCID: PMC10262878 DOI: 10.1002/ped4.12376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 01/29/2023] [Indexed: 06/17/2023] Open
Abstract
Importance Despite the high burden of respiratory infections among children, the production of exhaled particles during common activities and the efficacy of face masks in children have not been sufficiently studied. Objective To determine the effect of type of activity and mask usage on exhaled particle production in children. Methods Healthy children were asked to perform activities that ranged in intensity (breathing quietly, speaking, singing, coughing, and sneezing) while wearing no mask, a cloth mask, or a surgical mask. The concentration and size of exhaled particles were assessed during each activity. Results Twenty-three children were enrolled in the study. Average exhaled particle concentration increased by intensity of activity, with the lowest particle concentration during tidal breathing (1.285 particles/cm3 [95% CI 0.943, 1.627]) and highest particle concentration during sneezing (5.183 particles/cm3 [95% CI 1.911, 8.455]). High-intensity activities were associated with an increase primarily in the respirable size (≤ 5 µm) particle fraction. Surgical and cloth masks were associated with lower average particle concentration compared to no mask (P = 0.026 for sneezing). Surgical masks outperformed cloth masks across all activities, especially within the respirable size fraction. In a multivariable linear regression model, we observed significant effect modification of activity by age and by mask type. Interpretation Similar to adults, children produce exhaled particles that vary in size and concentration across a range of activities. Production of respirable size fraction particles (≤ 5 µm), the dominant mode of transmission of many respiratory viruses, increases significantly with coughing and sneezing and is most effectively reduced by wearing surgical face masks.
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Affiliation(s)
- Peter P. Moschovis
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Jesiel Lombay
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Jennifer Rooney
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Sara R. Schenkel
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Dilpreet Singh
- Department of Environmental HealthHarvard T. H. Chan School of Public HealthBostonMassachusettsUSA
- Department of Mechanical and Aerospace EngineeringRutgers University School of Public HealthNew BrunswickNew JerseyUSA
| | - Shawheen J. Rezaei
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Nora Salo
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Amanda Gong
- David Geffen School of Medicinethe University of California Los AngelesLos AngelesCaliforniaUSA
| | - Lael M. Yonker
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Jhill Shah
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Douglas Hayden
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Patricia L. Hibberd
- Department of Global HealthBoston University School of Public HealthBostonMassachusettsUSA
| | - Philip Demokritou
- Department of Environmental HealthHarvard T. H. Chan School of Public HealthBostonMassachusettsUSA
- Department of Mechanical and Aerospace EngineeringRutgers University School of Public HealthNew BrunswickNew JerseyUSA
| | - T. Bernard Kinane
- Department of PediatricsMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
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Viral Preservation with Protein-Supplemented Nebulizing Media in Aerosols. Appl Environ Microbiol 2023; 89:e0154522. [PMID: 36856430 PMCID: PMC10057872 DOI: 10.1128/aem.01545-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023] Open
Abstract
The outbreak of SARS-CoV-2 has emphasized the need for a deeper understanding of infectivity, spread, and treatment of airborne viruses. Bacteriophages (phages) serve as ideal surrogates for respiratory pathogenic viruses thanks to their high tractability and the structural similarities tailless phages bear to viral pathogens. However, the aerosolization of enveloped SARS-CoV-2 surrogate phi6 usually results in a >3-log10 reduction in viability, limiting its usefulness as a surrogate for aerosolized coronavirus in "real world" contexts, such as a sneeze or cough. Recent work has shown that saliva or artificial saliva greatly improves the stability of viruses in aerosols and microdroplets relative to standard dilution/storage buffers like suspension medium (SM) buffer. These findings led us to investigate whether we could formulate media that preserves the viability of phi6 and other phages in artificially derived aerosols. Results indicate that SM buffer supplemented with bovine serum albumin (BSA) significantly improves the recovery of airborne phi6, MS2, and 80α and outperforms commercially formulated artificial saliva. Particle sizing and acoustic particle trapping data indicate that BSA supplementation dose-dependently improves viral survivability by reducing the extent of particle evaporation. These data suggest that our viral preservation medium may facilitate a lower-cost alternative to artificial saliva for future applied aerobiology studies. IMPORTANCE We have identified common and inexpensive lab reagents that confer increased aerosol survivability on phi6 and other phages. Our results suggest that soluble protein is a key protective component in nebulizing medium. Protein supplementation likely reduces exposure of the phage to the air-water interface by reducing the extent of particle evaporation. These findings will be useful for applications in which researchers wish to improve the survivability of these (and likely other) aerosolized viruses to better approximate highly transmissible airborne viruses like SARS-CoV-2.
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Roger K, Atasi O, Lalanne B. Measuring mutual diffusion coefficients in aqueous binary mixtures with unidimensional drying cells. Phys Chem Chem Phys 2023; 25:994-998. [PMID: 36520070 DOI: 10.1039/d2cp03118c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chemical diffusion is a mass transport process caused by thermally generated motions of species. In a binary mixture, the diffusion of one species in one direction involves the diffusion of another species in the opposite direction, which corresponds to a single mutual diffusion coefficient. Here, we report a simple and general method to measure such coefficients in binary liquid mixtures, using the PNIPAM/water system as a study case. Experimentally, we show how a simple unidirectional drying cell coupled with a spatially-resolved characterization method such as Raman microscopy can yield concentration gradients developing in between two boundaries of known and constant chemical potential. Acquiring such gradients over time leads to a time-set that is shown to collapse to a single master curve using a change of variable. Such a scaling law offers a self-checking frame for solving analytically the diffusion-advection equation. As a result, we show that a simple analytical formula relates the measured concentration gradient with the concentration-dependent mutual diffusion coefficient. In the PNIPAM/water system, the mutual diffusion coefficient sharply decreases at low water content. Our work thus highlights the importance of considering the concentration-dependence of the mutual diffusion coefficient in complex aqueous solutions and provides a method to measure it.
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Affiliation(s)
- Kevin Roger
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, Institut National Polytechnique de Toulouse, Université Paul Sabatier, Toulouse, France.
| | - Omer Atasi
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, Institut National Polytechnique de Toulouse, Université Paul Sabatier, Toulouse, France.
| | - Benjamin Lalanne
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, Institut National Polytechnique de Toulouse, Université Paul Sabatier, Toulouse, France.
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Poydenot F, Abdourahamane I, Caplain E, Der S, Haiech J, Jallon A, Khoutami I, Loucif A, Marinov E, Andreotti B. Risk assessment for long- and short-range airborne transmission of SARS-CoV-2, indoors and outdoors. PNAS NEXUS 2022; 1:pgac223. [PMID: 36712338 PMCID: PMC9802175 DOI: 10.1093/pnasnexus/pgac223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/30/2022] [Indexed: 11/17/2022]
Abstract
Preventive measures to reduce infection are needed to combat the COVID-19 pandemic and prepare for a possible endemic phase. Current prophylactic vaccines are highly effective to prevent disease but lose their ability to reduce viral transmission as viral evolution leads to increasing immune escape. Long-term proactive public health policies must therefore complement vaccination with available nonpharmaceutical interventions aiming to reduce the viral transmission risk in public spaces. Here, we revisit the quantitative assessment of airborne transmission risk, considering asymptotic limits that considerably simplify its expression. We show that the aerosol transmission risk is the product of three factors: a biological factor that depends on the viral strain, a hydrodynamical factor defined as the ratio of concentration in viral particles between inhaled and exhaled air, and a face mask filtering factor. The short-range contribution to the risk, present both indoors and outdoors, is related to the turbulent dispersion of exhaled aerosols by air drafts and by convection (indoors), or by the wind (outdoors). We show experimentally that airborne droplets and CO2 molecules present the same dispersion. As a consequence, the dilution factor, and therefore the risk, can be measured quantitatively using the CO2 concentration, regardless of the room volume, the flow rate of fresh air, and the occupancy. We show that the dispersion cone leads to a concentration in viral particles, and therefore a short-range transmission risk, inversely proportional to the squared distance to an infected person and to the flow velocity. The aerosolization criterion derived as an intermediate result, which compares the Stokes relaxation time to the Lagrangian time-scale, may find application for a broad class of aerosol-borne pathogens and pollutants.
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Affiliation(s)
- Florian Poydenot
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Ismael Abdourahamane
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Elsa Caplain
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Samuel Der
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Jacques Haiech
- Cogitamus Laboratory and CNRS UMR 7242 BSC, 300 Bd Sébastien Brant, CS 10413, 67412 Illkirch Cedex, France
| | - Antoine Jallon
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Inés Khoutami
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Amir Loucif
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
| | - Emil Marinov
- Laboratoire de Physique de l’Ecole Normale Supérieure (LPENS), CNRS UMR 8023, Ecole Normale Supérieure, Université PSL, Sorbonne Université, and Université Paris Cité, 24 rue Lhomond, 75005 Paris, France
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