Facial Masking for Covid-19

To the Editor: We caution against incorporating hypotheses about masks functioning as effective “variolation” — a notion that was advanced by Gandhi and Rutherford in the Journal (online September 8) 1 — into public health messaging without considering the implications and nuances. The term “variolation” should be avoided because it is inaccurate with respect to coronaviruses, and it describes an obsolete and risky practice that was used for the iatrogenic inoculation of smallpox. There is insufficient evidence to support the claim that masks reduce the infectious dose of SARS-CoV-2 and the severity of Covid-19, much less that their use can induce . . .