From NCDHHS - The peer-reviewed scientific evidence for the protective effect of face masks and respiratory virus infection in healthcare and community settings is overwhelming. The following studies, all published in 2020, focus on the usefulness of wearing facemasks during the COVID-19 pandemic. Nearly all these studies conclude that, outside of the healthcare setting, wearing a face mask reduces one’s risk of being exposed to SARS CoV2 virus, and transmitting the virus to others, if infected. Controlled experiments similarly showed that mask wearing reduced the amount of exposure to virus particles. Importantly, countries, states and jurisdictions that imposed mask wearing mandates and encouraged adherence were generally associated with lower disease transmission and overall decreases in disease trends. You can download the studies from the NC DHHS website here.
Here are some additional resources on the importance of masks and facial coverings: