As I was writing Fear of a Microbial Planet last year, I noticed some patterns emerge. Again and again, I found examples of instances where, in a rational world, the actions of authorities in response to COVID or other disease threats should be obvious, expected, and in the best interests of the public. However, in each instance, I was compelled to acknowledge reality and follow-up with “But that didn’t happen.” Because the response often wasn’t rational—it was mainly driven by politics and hysteria, and every irrational and non-evidence-supported act could be explained through this lens. As a result, the phrase is by far the most repeated in the book, and so I thought it would be interesting to compile ten examples of when a strong denial of reality ruled and common sense was abandoned.