body defence

[mikeportnoy]

how man prevent the entrance of microorganisms into the body by his natural means ?

[MichaelXY]

Lots of smoking and drinking hard liquor
Skin and mucus also help.

[alextemplet]

Don't forget the coffee!

[canalon]

Skin, mucous, bacteriophages are helping. You can use those as keywords to start searching

[MichaelXY]

Skin, mucous, bacteriophages are helping. You can use those as keywords to start searching

I did say skin and mucus. Was not sure if it was mucus or mucous...

Technically though mucous should not count as it is in the body and not outside, it just protects from material reaching organs

[canalon]

Sorry I skipped your second sentence. And my spelling might not be accurate (I know I am not a native speaker, so I have no excuse to torture English, but I am fallible).

But muc(o)us should count as it is produced by the body in order to prevent the entry of external and unwanted things. The water filled moat is part of the castle defense system, even if it is outside the walls.

[alextemplet]

I am a native speaker, and even I'm not sure how to spell it. I think it's mucus. Be careful, though, since words are often spelled differently depending on which side of the Atlantic you're on.