Observation and quantification of respiratory droplets by laser light scattering
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Principal Investigator: Adriaan Bax Organization: NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES Fiscal Year: 2024 Award: $658,712 Funding agency: National Institute of Diabetes and Digestive and Kidney Diseases The soft palate and back of the throat represent vulnerable early infection sites for SARS-CoV-2, influenza, streptococci, and many other pathogens. We demonstrated in a laboratory experiment that voluntary generation of snoring sounds causes aerosolization of pharyngeal fluid that covers these surfaces, which previously has escaped detection because the inspired airstream carries the micron-sized droplets into the lung, inaccessible to traditional aerosol detectors. While many of these droplets will settle in the lower respiratory tract, a fraction of the respirable smallest droplets remains airborne and can be detected in exhaled breath. We distinguished these exhaled droplets from those generated by the underlying breathing activity by using tri-methylglycine as a chemical tracer, thereby proving their existence. The direct transfer of pharyngeal fluids and their pathogens into the deep lung by snoring represents a plausible mechanistic link between the clinically recognized association between sleep-disordered breathing and pneumonia incidence. Terms: <2019 novel corona virus><2019 novel coronavirus><2019-nCoV><Aerosols><Air><Area><Back><Breathing><COVID associated pneumonia><COVID induced pneumonia><COVID pneumonia><COVID related pneumonia><COVID-19 associated pneumonia><COVID-19 induced pneumonia><COVID-19 pathogenesis><COVID-19 pneumonia><COVID-19 related pneumonia><COVID-19 viral pneumonia><COVID-19 virus><COVID19 pathogenesis><COVID19 virus><Chemicals><Clinical><CoV-2><CoV2><Deposit><Deposition><Detection><Development><Diffuse><Dorsum><Escalator><Exhalation><Exhaling><Generations><Grippe><Incidence><Infection><Influenza><Inhalation><Inhaling><Laser Electromagnetic><Laser Radiation><Lasers><Link><Liquid substance><Lobar Pneumonia><Location><Lower respiratory tract structure><Lung><Lung Respiratory System><Methylglycine><Microscopic><N-Methylglycine><N-methyl-glycine><Pharyngeal structure><Pharynx><Physics><Pneumococcal Pneumonia><Pneumonia><Process><Research><Respiratory Aspiration><Respiratory Expiration><Respiratory Inspiration><SARS corona virus 2><SARS-CO-V2><SARS-COVID-2><SARS-CoV-2><SARS-CoV-2 associated pneumonia><SARS-CoV-2 induced pneumonia><SARS-CoV-2 pneumonia><SARS-CoV-2 related pneumonia><SARS-CoV-2 viral pneumonia><SARS-CoV2><SARS-associated corona virus 2><SARS-associated coronavirus 2><SARS-coronavirus-2><SARS-related corona virus 2><SARS-related coronavirus 2><SARSCoV2><Sarcosine><Severe Acute Respiratory Coronavirus 2><Severe Acute Respiratory Distress Syndrome CoV 2><Severe Acute Respiratory Distress Syndrome Corona Virus 2><Severe Acute Respiratory Distress Syndrome Coronavirus 2><Severe Acute Respiratory Syndrome CoV 2><Severe Acute Respiratory Syndrome-associated coronavirus 2><Severe Acute Respiratory Syndrome-related coronavirus 2><Severe acute respiratory syndrome associated corona virus 2><Severe acute respiratory syndrome coronavirus 2><Severe acute respiratory syndrome related corona virus 2><Site><Sleep Apnea><Sleep Apnea Syndromes><Sleep Hypopnea><Sleep-Disordered Breathing><Snoring><Soft Palate><Stream><Streptococcus><Surface><Throat><Tracer><Velum Palatinum><Wuhan coronavirus><aerosolized><aspirate><coronavirus disease 2019 associated pneumonia><coronavirus disease 2019 induced pneumonia><coronavirus disease 2019 pathogenesis><coronavirus disease 2019 pneumonia><coronavirus disease 2019 related pneumonia><coronavirus disease 2019 virus><coronavirus disease associated pneumonia><coronavirus disease induced pneumonia><coronavirus disease pneumonia><coronavirus disease related pneumonia><coronavirus disease-19 pathogenesis><coronavirus disease-19 pneumonia><coronavirus disease-19 virus><detector><developmental><fluid><hCoV19><inspiration><lab assignment><lab experiment><laboratory activity><laboratory assignment><laboratory exercise><laboratory experiment><light scattering><liquid><lower respiratory tract><nCoV2><pathogen><pneumonia due to COVID><pneumonia due to COVID-19><pneumonia due to SARS-CoV-2><pneumonia due to coronavirus disease><pneumonia due to coronavirus disease 2019><pneumonia due to severe acute respiratory syndrome coronavirus 2><pneumonia in COVID><pneumonia in COVID-19><pneumonia in SARS-CoV-2><pneumonia in coronavirus disease><pneumonia in coronavirus disease 2019><pneumonia in severe acute respiratory syndrome coronavirus 2><pulmonary><respiratory><severe acute respiratory syndrome coronavirus 2 associated pneumonia><severe acute respiratory syndrome coronavirus 2 induced pneumonia><severe acute respiratory syndrome coronavirus 2 pneumonia><severe acute respiratory syndrome coronavirus 2 related pneumonia><sleep-related breathing disorder><soft tissue><sound><vibration>