The effect of body position while coughing on the airborne transmission of pathogens

ABSTRACT

Given the recent acceptance of the central role of airborne transmission for SARS-CoV-2, increased attention has been paid to the dispersion of respiratory droplets in different scenarios. Studies including numerical simulations have been conducted on methods for breaking the chains of transmission. Here, we present the first such study on the impact of body position while coughing on the dispersion of respiratory droplets. Four scenarios are examined, including normal standing, bending the head at different angles, coughing into the elbow in still air, and a gentle breeze from the front and behind. The model showed that an uncovered cough is dangerous and causes many droplets to enter the environment, posing a cross-contamination threat to the others. Droplets with an initial diameter smaller than 62.5 μm remain suspended in windless air for more than 3 min. In the presence of wind, these droplets move with the wind flow and may travel long distances greater than 3.5 m. The model showed that covering the mouth with the elbow while coughing is clearly the best strategy for reducing airborne transmission of exhaled pathogens. About 62% of the initial number of droplets deposit on the cougher's elbow immediately after the cough and have no chance of spreading through the air in both windless and windy conditions. Covering the cough in windless or light breeze conditions also causes the upward thermal plume around the body to expel many small droplets. [ FROM AUTHOR] Copyright of Physics of Fluids is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)