In November 2020, the US was averaging more than 1 million new coronavirus disease 2019 (COVID-19) cases per week, an astounding number. To make progress against the pandemic, routine and universal use of face masks throughout society is essential.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is “transmitted predominantly by respiratory droplets generated when people cough, sneeze, sing, talk, or breathe,” and masks “reduce the emission of virus-laden droplets” and “help reduce the inhalation of these droplets by the wearer.”1 In the face of severe shortages of medical-grade masks, public health officials have recommended that the general public wear consumer-grade face masks to protect themselves against COVID-19, such as “non-valved multi-layer cloth masks.”1 However, there has been considerable discussion and debate about the types of masks that would be best, especially because the shortage of medical grade masks is not as acute as it once was (N95 masks remain in much shorter supply).