Sweet Blood
I never knew how schweeeet my blood is till recently. Whenever I go into the jungle, despite the many precautions I take, I still get at least one leech or 'pacat' (in malay) bite on my feet. And the weird thing is, no one else seems to get bitten except me. I have grown immune to it now.
In case you're wondering if it hurts, it doesn't. Just remember not to pull it off if you find one sucking your blood. Their teeth has an anticoagulant agent which makes it easy for it to draw blood from it's victim. In this context, I am the victim. Once it's full, it'll drop off on its own. If you can't wait for it to get full, you can use a little salt to sprinkle on it or use a burning cigarette (one of the only useful things having a ciggie around).
Do make sure to clean and disinfect your war wounds when you get the chance. Do not scratch or it'll manifest into a nasty sore which will leave scarring. You wouldn't want that.