How coronavirus survives for hours in aerosols

Abstract

COVID (CoronaVirus Disease)-19, caused by severe acute respiratory syndrome-CoronaVirus-2 (SARS-CoV-2) virus, predominantly transmits via airborne route, as highlighted by recent studies. Furthermore, recently published titer measurements of SARS-CoV-2 in aerosols have disclosed that the coronavirus can survive for hours. A consolidated knowledge on the physical mechanism and governing rules behind the significantly long survival of coronavirus in aerosols is lacking, which is the subject of the present investigation. We model the evaporation of aerosolized droplets of diameter m. The conventional diffusion-limited evaporation is not valid to model the evaporation of small size ( μ m–nm) droplets since it predicts drying time on the order of milliseconds. Also, the sedimentation timescale of desiccated droplets is on the order of days and overpredicts the virus survival time; hence, it does not corroborate with the above-mentioned titer-decay timescale. We attribute the virus survival timescale to the fact that the drying of small ( m–nm) droplets is governed, in principle, by the excess internal pressure within the droplet, which stems from the disjoining pressure due to the cohesive intermolecular interaction between the liquid molecules and the Laplace-pressure. The model predictions for the temporal reduction in the aerosolized droplet number density agree well with the temporal decay of virus titer. The findings, therefore, provide insight on the survival of coronavirus in aerosols, which is particularly important to mitigate the spread of COVID-19 from indoors.

Airborne virus transmission under different weather conditions

“…We have observed that the droplets of size 25 µm evaporates to aerosols with mean radius of 2 µm. The motion of these aerosols are controlled by the diffusive force and therefore, these droplets have the ability float in the air for longer time (see also [35]). The results displayed in Fig.…”

Políticas públicas promovidas para el sistema educativo a partir de propagación del COVID-19

“…En el caso del SARS-CoV-2, estudios demuestran que puede mantenerse activo en aerosoles y superficies, no obstante, es inactivado por desinfectantes comunes como alcohol o peróxido de hidrógeno, en tal sentido, un protocolo adecuado de limpieza y desinfección de mobiliario y equipamiento constituye una de las principales herramientas para prevenir el contagio por coronavirus en los recintos universitarios. Adicionalmente es importante complementar esta medida con la verificación y análisis periódico de las superficies, mediante ensayos para la detección del SARS-CoV-2, que valide los procedimientos de limpieza y desinfección y garantice un espacio académico más seguro para las clases presenciales y semipresenciales (Lema, 2020;Chatterjee et al, 2021).…”

Computational characterization of the behavior of a saliva droplet in a social environment

“…It has been researched with the aim of providing a solution to the famous SARS-CoV-2, but all these studies are based on explaining the functioning of the exhaled air to the environment, which is the route of contagion of all diseases, either by major droplets or by aerosols, according to Leung et al 4 . The human body exhales particles between 10 µm and 100 µm of diameter in a sneeze, according to the numerical study of Chillón et al 4 , but it is not considered aerosol until the particle reaches 5 µm of diameter, Chatterjee et al 5 . When a person coughs, speaks, or sneezes, exhales to the environment particles with great contagion power.…”