The perspective of fluid flow behavior of respiratory droplets and aerosols through the facemasks in context of SARS-CoV-2

Abstract

In the unfortunate event of the current ongoing pandemic COVID-19, where vaccination development is still in the trial phase, several preventive control measures such as social distancing, hand-hygiene, and personal protective equipment have been recommended by health professionals and organizations. Among them, the safe wearing of facemasks has played a vital role in reducing the likelihood and severity of infectious respiratory disease transmission. The reported research in facemasks has covered many of their material types, fabrication techniques, mechanism characterization, and application aspects. However, in more recent times, the focus has shifted toward the theoretical investigations of fluid flow mechanisms involved in the virus-laden particles’ prevention by using facemasks. This exciting research domain aims to address the complex fluid transport that led to designing a facemask with a better performance. This Review discusses the recent updates on fluid flow dynamics through the facemasks. Key design aspects such as thermal comfort and flow resistance are discussed. Furthermore, the recent progress in the investigations on the efficacy of facemasks for the prevention of COVID-19 spread and the impact of wearing facemasks is presented.

Computer simulation of the SARS-CoV-2 contamination risk in a large dental clinic

“…Behaviors such as self-quarantining, social distancing, and hand sanitizing minimize contact transmission of SARS-CoV-2. Airborne transmission can be reduced by the use of face-coverings, which prohibit exhalation and inhalation of virus-bearing aerosols ( Leung et al , 2020 ; Dbouk and Drikakis, 2020b ; Kumar and Lee, 2020 ; and Akhtar et al , 2020 ). However, face-coverings, such as masks, alone do not completely eliminate the risk of infection due to the possibility of leakage ( Verma et al , 2020 ).…”

An opinion on the multiscale nature of Covid-19 type disease spread

“…Although all face coverings provide some protection, their relative efficacy depends on the type of mask used. Several studies [ [69∗∗] , [70] , [71] , [72] , [73∗] ] have been carried out in recent times, focusing on investigating mask efficacy. Fischer et al [ 69 ] used a laser-based optical measurement technique to determine the effectiveness of different locally available face coverings (compared to no face-covering) in restricting ejected droplets during human speech.…”

Airborne virus transmission via respiratory droplets: Effects of droplet evaporation and sedimentation

“…Wearing mouth covers by both the infected person and passive bystanders not only significantly decreases this virion inhalation rate [ 81 ], but it also decreases the travel distance of the droplets by half [ 82 ]. However, the use of a mask is inadequate alone because many droplets still spread around and away from the cover during cough cycles [ 82 ] and aerosol droplets can both penetrate and circumnavigate masks [ 5 , 83 ]. In particular, using a face mask that loosely fits the face [ 84 ] or covering a tight-fitting mask by cloth or medical masks [ 82 ] can increase the possibility of leakage around the mask’s edge.…”