Use of Masks as a Preventative Public Health Strategy to Limit the Spread of COVID-19

SARS-CoV-2 coronavirus (COVID-19) is a respiratory infectious disease that has caused a global pandemic of unprecedented proportions. There has been a lot of discussion and debate in social media and by public health experts about the effectiveness of masks as a preventative strategy to decrease transmission of this virus. There are two modes in which mask may be beneficial: i) To serve as a physical barrier against the virus entering or leaving the oral-nasal passages of mask wearers, and ii) to decrease the risk that the person wearing the mask might pass the virus on to someone else (e.g., via coughing). The focus of this review is on the efficacy of different masks-types, and their demonstrated effectiveness in mitigating transmission from a global perspective. Our findings reveal that the use of commercially manufactured mask greatly decreases the distribution of COVID-19, whereas single layer homemade masks also provide protection by decreasing the viral dose of exposure and limit outward aerosol particle emissions. We argue that masks are a critical component in the arsenal of public health strategies to decrease transmission of viruses, including handwashing, maintaining social distancing (2 meters), limiting large gatherings of people, isolation of suspected cases, screening, and contact tracing.