dmaziuk
Contributor
I was taught that fairly forceful injection of water up into the nose was required for infection, not just a little sprinkle of water into the nose.
Define "forceful" -- I suspect 90% of child-athlete swimmers will tell you we can get water into our sinus cavities and walk around with it for days without caring. (OK, salt water: fresh water stings a little and chlorinated pool water stings more, but you learn to man up and take it when it happens in a middle of a race.)