The problem of unsound or indecisive policy creating bad messaging has been repeated over and over again throughout the pandemic, which has deepened skepticism about the agency's recommendations and created a fertile environment for disinformation to flourish.

A year after the first masking flip-flop, the CDC stumbled on masks again. In April 2021, the agency urged vaccinated people to continue wearing masks in most indoor settings to reduce transmission before reversing itself and saying that vaccinated people could feel free not to wear masks indoors unless it was required by a local or state government.

Many public health experts believed the decision to relax the masking guidance for vaccinated people was premature and, just a few months later when the delta variant drove up cases, the CDC changed course again and recommended everyone, including vaccinated people, wear masks when indoors in public.

Contrast the whiplash in the US with the approach in Canada, which issued a much more limited change to its masking guidance around the same time and didn't need to quickly revise it. Canadians were urged to keep masking, with the one exception of small indoor gatherings with other vaccinated people. Those recommendations remain more or less the same to this day.