[dragonwriter]

> They're more likely to work, because they go in the places (your nose) that need to be sterilized.

That doesn't make much sense; vaccines aren't topical treatments for current infections but systemic preparation against future infections.

[astrange]

There's special antibodies for the nose and other membranes. The immune system is incredibly complicated.

https://en.wikipedia.org/wiki/Immunoglobulin_A