Critical appraisal of the new CDC article on the effectiveness of masks for the prevention of Covid-19.

Mask studies reach a new scientific low point – Vinay Prasad’s Observations and Thoughts

Original Study: Effectiveness of Face Mask or Respirator Use in Indoor Public Settings for Prevention of SARS-CoV-2 Infection — California, February–December 2021 – CDC Morbidity and Mortality Weekly Report

Related Studies:

Time to upgrade from cloth and surgical masks to respirators? Your questions answered.

CDC urges Americans to wear most-protective mask or respirator that fits well and that they’ll wear consistently.

Modeling COVID-19 mortality across 44 Countries: Face covering may reduce deaths.

What can masks do? Part 2: What makes for a good mask study — and why most fail.

Opinion | Why Are Americans Still—Still!—Wearing Cloth Masks?

Evidence shows that, yes, masks prevent COVID-19 – and surgical masks are the way to go.

Face masks for COVID pass their largest test yet – “A rigorous study finds that surgical masks are highly protective, but cloth masks fall short”.

[Preprint] Largest study of masks yet details their importance in fighting Covid-19.

Commentary on Twitter

A new @CDCMMWR study shows that people who reported always wearing masks or respirators in indoor public settings in California were less likely to test positive for #COVID19 compared with those who reported not wearing a face covering. Learn more. https://t.co/T8gaqiPHyI pic.twitter.com/6UJ9cs60NK

— CDC (@CDCgov) February 4, 2022