It seems clear that maks wearing reduces spread somewhat, but note that this is because of reducing spread from infectious individuals, especially pre-symptomatic and asymptomatic people, not protecting mask wearers. The early skepticism was in part based on the assumption, which in March seemed to have been shared by both promoters and skeptics, that the benefits were that masks were individually protective, rather than that they helped population-level spread reduction.
The early *arguments* I saw were mainly about whether masks meaningfully reduced the wearer’s chances of getting infected. But it was already conventional wisdom that masks did meaningfully reduce the wearer’s chances of infecting others, people just weren’t taking the next step of arguing for general mask use on these grounds. For example, the early March CDC recommendation (linked in the anti-CDC LW post) was:
CDC does not recommend that people who are well wear a facemask to protect themselves from respiratory diseases, including COVID-19.
Facemasks should be used by people who show symptoms of COVID-19 to help prevent the spread of the disease to others. The use of facemasks is also crucial for health workers and people who are taking care of someone in close settings (at home or in a health care facility).
By mid March, there were organized efforts to increase mask use on the grounds that it reduced the wearer’s chances of infecting others. The Czech government (which mandated mask use on March 19) and the #Masks4All campaign were the most prominent ones that I saw—both encouraged people to make their own cloth masks and used the slogan “My mask protects you, your mask protects me” (they may also have talked about some risk-reduction benefits for the wearer). A quick search turns up this March 14 video (in Czech, with English closed captioning available) as the earliest source I could quickly find clearly making this case for widespread mask use.
Yes—it took me until mid or late March to be fully on board. See my comment here to a post arguing for pushing handwashing instead of suggesting masks, which I changed my mind about in mid to late March.
The early *arguments* I saw were mainly about whether masks meaningfully reduced the wearer’s chances of getting infected. But it was already conventional wisdom that masks did meaningfully reduce the wearer’s chances of infecting others, people just weren’t taking the next step of arguing for general mask use on these grounds. For example, the early March CDC recommendation (linked in the anti-CDC LW post) was:
By mid March, there were organized efforts to increase mask use on the grounds that it reduced the wearer’s chances of infecting others. The Czech government (which mandated mask use on March 19) and the #Masks4All campaign were the most prominent ones that I saw—both encouraged people to make their own cloth masks and used the slogan “My mask protects you, your mask protects me” (they may also have talked about some risk-reduction benefits for the wearer). A quick search turns up this March 14 video (in Czech, with English closed captioning available) as the earliest source I could quickly find clearly making this case for widespread mask use.
Yes—it took me until mid or late March to be fully on board. See my comment here to a post arguing for pushing handwashing instead of suggesting masks, which I changed my mind about in mid to late March.