Supporting data for "The rapid natural viral inactivation in an evaporating droplet"

Droplet infection transmission has again become one of the most heated topics due to the SARS-CoV-2 pandemic in 2019. While the viability decay of infectious droplets due to environmental exposure has been studied for nearly a century, the mechanisms of viability decay in respiratory droplets is still unclear, and it lacks a model to evaluate short-range (i.e., conversational distance) droplet viability decay. Recent experimental setup, specifically the droplet levitation device, only allowed capturing droplets after 5 seconds of environmental exposure. Unfortunately, experiment showed the infectivity decay of a large droplet (>50 micrometers in diameter) occurred before 5 seconds, and a new setup was needed to investigate this rapid decay.

In this study, we proposed a new setup to capture and analyze droplets after 0.1 to ~9 seconds from initial droplet generation. The droplet drying dynamic was simulated to explain the viability decay measured by the droplet experiment. The simulation results of the droplet composition throughout the evaporation process under various humidity levels are shown here.