Masks help stop the spread of coronavirus – the science is simple and I’m one of 100 experts urging governors to require public mask-wearing

Masks help stop the spread of coronavirus – the science is simple and I’m one of 100 experts urging governors to require public mask-wearing
https://theconversation.com/masks-help-stop-the-spread-of-coronavirus-the-science-is-simple-and-im-one-of-100-experts-urging-governors-to-require-public-mask-wearing-138507

Universal Masking is Urgent in the COVID-19 Pandemic: SEIR and Agent Based Models, Empirical Validation, Policy Recommendations
De Kai, Guy-Philippe Goldstein, Alexey Morgunov, Vishal Nangalia, Anna Rotkirch
We present two models for the COVID-19 pandemic predicting the impact of universal face mask wearing upon the spread of the SARS-CoV-2 virus--one employing a stochastic dynamic network based compartmental SEIR (susceptible-exposed-infectious-recovered) approach, and the other employing individual ABM (agent-based modelling) Monte Carlo simulation--indicating (1) significant impact under (near) universal masking when at least 80% of a population is wearing masks, versus minimal impact when only 50% or less of the population is wearing masks, and (2) significant impact when universal masking is adopted early, by Day 50 of a regional outbreak, versus minimal impact when universal masking is adopted late. These effects hold even at the lower filtering rates of homemade masks. To validate these theoretical models, we compare their predictions against a new empirical data set we have collected that includes whether regions have universal masking cultures or policies, their daily case growth rates, and their percentage reduction from peak daily case growth rates. Results show a near perfect correlation between early universal masking and successful suppression of daily case growth rates and/or reduction from peak daily case growth rates, as predicted by our theoretical simulations.
Our theoretical and empirical results argue for urgent implementation of universal masking. As governments plan how to exit societal lockdowns, it is emerging as a key NPI; a "mouth-and-nose lockdown" is far more sustainable than a "full body lockdown", on economic, social, and mental health axes. An interactive visualization of the ABM simulation is at this http URL. We recommend immediate mask wearing recommendations, official guidelines for correct use, and awareness campaigns to shift masking mindsets away from pure self-protection, towards aspirational goals of responsibly protecting one's community.
https://www.researchgate.net/publication/340933456_Universal_Masking_is_Urgent_in_the_COVID-19_Pandemic_SEIR_and_Agent_Based_Models_Empirical_Validation_Policy_Recommendations

Still Confused About Masks? Here’s the Science Behind How Face Masks Prevent Coronavirus
https://www.ucsf.edu/news/2020/06/417906/still-confused-about-masks-heres-science-behind-how-face-masks-prevent

Identifying airborne transmission as the dominant route for the spread of COVID-19
Significance
We have elucidated the transmission pathways of coronavirus disease 2019 (COVID-19) by analyzing the trend and mitigation measures in the three epicenters. Our results show that the airborne transmission route is highly virulent and dominant for the spread of COVID-19. The mitigation measures are discernable from the trends of the pandemic. Our analysis reveals that the difference with and without mandated face covering represents the determinant in shaping the trends of the pandemic. This protective measure significantly reduces the number of infections. Other mitigation measures, such as social distancing implemented in the United States, are insufficient by themselves in protecting the public. Our work also highlights the necessity that sound science is essential in decision-making for the current and future public health pandemics.
https://www.pnas.org/content/117/26/14857