For Whom Do The Covid Fact Checkers Really Work?

I recently came across two tweets that caught my eye.

Here is the first one from the CDC director:

Masks can help reduce your chance of #COVID19 infection by more than 80%.
Masks also help protect from other illnesses like common cold and flu. Wearing a mask- along w/ getting vaccinated- are important steps to stay healthy. #WeCanDoThis @HHSgov https://t.co/bfOV5VzBpq pic.twitter.com/6DGj8nwPgD

— Mandy K. Cohen, MD, MPH (@CDCDirector) November 5, 2021

And here is the second one, from a couple months back:

Posts continue to circulate online falsely claiming that COVID-19 survivors don’t need vaccines because of natural immunity. In fact, that protection is variable and not long-lasting, so vaccines are still recommended. Here’s our recent look at this claim. https://t.co/NHiepR24T1

— AP Fact Check (@APFactCheck) September 29, 2021

Together they got me thinking. What do they have in common? What do they tell us about the state of the public communication of science?

Let’s start with the one by Dr. Walensky. I don’t know how to put this politely, but it is a lie, and a truly unbelievable one at that.

First, of all, if it were true, it would mean that masking was more effective that the J&J vaccine (implausible). Second of all, we have actual cluster RCT data from Bangladesh showing a 11% (relative risk reduction). This occurred in a massive trial where masks were provided for free and encouraged. Even here, only surgical masks worked, and cloth did no...