Board Thread:General Discussion/@comment-6192846-20130913170916/@comment-6192846-20140612151053

Master of Lemmings wrote: I'm not entirely sure putting the words "vaccine" in katakana is necessarily a sign of emphasis, as it's actually very common for the word to be written in katakana. When I say "emphasis", I'm talking about the usage of ワクチン vs 医,  薬,  or even メディシン. The prose specifically uses the term "vaccine" and not any other term for a medicine, drug, or other healing agent that could serve the same focus.

As far as the use, I'm not sure at what point we should just settle for "it's magic".