Hi, author of the post here. I tried to include some info on temperature requirements and how cold chain distribution works, but it's hard to capture that comprehensively because it varies a lot geographically.

While I do appreciate how difficult it is to distribute the Pfizer-BioNTech vaccine at -70 C, I am still puzzled by how deep into the distribution this temperature gets maintained. As far as I know, the spec is that the vaccine can be stored (and transported) at regular fridge temperatures for up to 5 days. It seems like everyone (in the US anyway) is focused on maintaining -70C all the way to the point of use. What about the alternative of thawing it at some distribution center and focusing efforts on getting it into a person within five days after that?