@Duribu Not voice acting. What might be just a typical cold for Sakuma could be a career ender for Wanko, hence the extra precautions.
edit: nvm misread the context.
Considering it's always shown that people with 38ish deg temperature are hallucinating, missing time, and close to dying, I just assume that either people in Japan go through colds differently, or it's a different virus. From my experience, those symptoms shouldn't set in unless the temperature is around 39.5+.
I don't remember ever losing focus that much just because a loved one had the flu (not even going to mention colds, because japanese manga/anime colds clearly aren't colds).