Wearing face masks in group settings independently reduces (4,5,6,10,11) but does not eliminate (1,7) the risk of transmitting SARS-CoV-2. Other possible variables influencing the odds of transmission include presence or absence of mask mandates (6), degree of compliance with mask mandates or requests (10), prevalence of the virus in the community, number of attendees, number of unvaccinated attendees, number of infected attendees, locally dominant variant of the virus, spacing, ventilation, and duration of exposure. There is experimental evidence from a study in nonhuman primates (3) that the exposure dose of SARS-CoV-2 independently influences what happens next along a continuum ranging from no disease to death. Wearing a mask can provide valuable benefit to self and others even when it fails to protect completely.
"Personal freedom" has been raised as an issue in mask wearing (12), especially in the context of mandates. Masks have acquired a new symbolism (8) in the pandemic. Prevalence of mask wearing has varied among U.S. states (8) as well as among other countries (9). "Freedom" is just a cover for the real issue, which is identity politics (2), given that mandates unrelated to COVID-19 traditionally have been accepted without drama. In some subcultures, wearing a mask in public looks weak (8). Any government mandate for highly visible attire that conflicts with a person's self-identity and how they wish to be seen by others (8) is likely to be greeted with hostility--and understandably so. The demonstrable value of masking for preventing this particular disease has been compromised by those who have made it a political issue. This kind of damage is hard to undo.
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