Larger, heavier respiratory droplets can travel up to 6 feet, but then they fall to the ground. Smaller, aerosolized particles, however, can get caught in air flows and move throughout a space, infecting people at further distances.
"It's really the size of the droplet nuclei that defines an aerosol-borne infection versus a droplet-borne infection," said Monica Gandhi, MD, MPH, an infectious disease expert at the University of California San Francisco. She added that in recognizing the airborne nature of COVID-19, we acknowledge that "it's most effectively transmitted in closed, indoor spaces, and that ventilation is one of the most important things to mitigate the virus."
