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Prevea Health

How masks work


We all produce respiratory droplets, which are most often invisible to the naked eye, every day. These respiratory droplets are expelled into the air when we cough, sneeze, talk and/or raise our voices (such as while shouting or singing).

When someone has COVID-19, they can spread the disease to others if their droplets are inhaled by or come in direct contact with the face of another person. We have learned through various recent studies that, in instances where physical distancing is not possible, masks provide additional protection because they act as a simple barrier for those respiratory droplets.

Evidence for Effectiveness of Cloth Face Coverings - CDCSome people infected with COVID-19 have symptoms, such as coughing and sneezing. However, in many cases, those infected with COVID-19 do not show any symptoms at all, and may not realize they are infected.  
This is why the Centers for Disease Control and Prevention (CDC), the World Health Organization (WHO) and many other health care organizations, such as Prevea, recommend that all who are able, (not just those infected with COVID-19 or those showing symptoms of COVID-19) wear a mask outside in public settings and around people outside of your household during the COVID-19 pandemic.
Wearing a mask is not guaranteed to prevent you from contracting COVID-19. However, when you wear a mask, you are helping to protect others from contracting the virus by creating a simple barrier between your respiratory droplets and those around you. This practice is most effective when you also physically distance yourself from others (at least 6-feet) and practice good hygiene.

Scientific studies show effectiveness of masks

Face Masks Against COVID-19: An Evidence Review

Visualizing the effectiveness of face masks in obstructing respiratory jets

Additional emerging evidence  about the effectiveness of cloth masks