ArticleProceedings of the National Academy of Sciences of the United States of America2020
Speech can produce jet-like transport relevant to asymptomatic spreading of virus.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 70 papers.
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Who cites it
70 citing papers in PubMed, 5 citations in OpenAlex.
- Automated, multiparametric monitoring of respiratory biomarkers and vital signs in clinical and home settings for COVID-19 patients.Proceedings of the National Academy of Sciences of the United States of America · 2021Trial
- The Exchange Breathing Method for Seizure Intervention: A Historical and Scientific Review of Epilepsy and Its Evolving Therapeutic Paradigms.Journal of personalized medicine · 2025Review
- Fluid dynamical pathways of airborne transmission while waiting in a line.Science advances · 2025Article
- Perspectives on physics-based one-dimensional modeling of lung physiology.Frontiers in physiology · 2025Article
- The influence of glottal and respiratory factors on aerosol emission during phonation.PloS one · 2025Article
- Airborne respiratory aerosol transport and deposition in a two-person office using a novel diffusion-based numerical model.Journal of exposure science & environmental epidemiology · 2024Article
- A safer framework to evaluate characterization technologies of exhaled biologic materials using electrospun nanofibers.Nanoscale · 2023Article
- Influence of two-dimensional expiratory airflow variations on respiratory particle propagation during pronunciation of the fricative [f].Journal of aerosol science · 2023Article
- From Microscopic Droplets to Macroscopic Crowds: Crossing the Scales in Models of Short-Range Respiratory Disease Transmission, with Application to COVID-19.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2023Article
- Large eddy simulation of droplet transport and deposition in the human respiratory tract to evaluate inhalation risk.PLoS computational biology · 2023Article
- Predominance of inhalation route in short-range transmission of respiratory viruses: Investigation based on computational fluid dynamics.Building simulation · 2023Article
- First impressions of a new face are shaped by infection concerns.Evolution, medicine, and public health · 2023Article
- Aerosols, airflow, and more: examining the interaction of speech and the physical environment.Frontiers in psychology · 2023Article
- Inhalation of virus-loaded droplets as a clinically plausible pathway to deep lung infection.Frontiers in physiology · 2023Article
- Multiscale landscaping of droplet wettability on fibrous layers of facial masks.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- Dynamics of plosive consonants via imaging, computations, and soft electronics.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- Effects of upper respiratory tract anatomy and head movement on the buoyant flow and particle dispersion generated in a violent expiratory event.Journal of aerosol science · 2022Article
- Risk assessment for long- and short-range airborne transmission of SARS-CoV-2, indoors and outdoors.PNAS nexus · 2022Article
- Snoring may transmit infectious aerosols from the upper to the lower respiratory tract.Medical hypotheses · 2022Article
- Assessing suspension and infectivity times of virus-loaded aerosols involved in airborne transmission.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
10 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Many scientific reports document that asymptomatic and presymptomatic individuals contribute to the spread of COVID-19, probably during conversations in social interactions. Droplet emission occurs during speech, yet few studies document the flow to provide the transport mechanism. This lack of understanding prevents informed public health guidance for risk reduction and mitigation strategies, e.g., the "6-foot rule." Here we analyze flows during breathing and speaking, including phonetic features, using orders-of-magnitude estimates, numerical simulations, and laboratory experiments. We document the spatiotemporal structure of the expelled airflow. Phonetic characteristics of plosive sounds like "P" lead to enhanced directed transport, including jet-like flows that entrain the surrounding air. We highlight three distinct temporal scaling laws for the transport distance of exhaled material including 1) transport over a short distance (<0.5 m) in a fraction of a second, with large angular variations due to the complexity of speech; 2) a longer distance, ∼1 m, where directed transport is driven by individual vortical puffs corresponding to plosive sounds; and 3) a distance out to about 2 m, or even farther, where sequential plosives in a sentence, corresponding effectively to a train of puffs, create conical, jet-like flows. The latter dictates the long-time transport in a conversation. We believe that this work will inform thinking about the role of ventilation, aerosol transport in disease transmission for humans and other animals, and yield a better understanding of linguistic aerodynamics, i.e., aerophonetics.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.