Most of the places people are likely to explore around Tasmania are moist and perfect environments for these nasty little critters. Luckily I have been fortunate enough not to actually find one sampling the taste of my blood so far, but it is bound to happen.
If you are unfortunate enough to have one attach, most people suggest that salt will make them let go, or a bit of heat, applying a lit cigarette for example, will get rid of the critter. Doi not scratch the bite area no matter how much it itches as this will only make it worse.
The leech in the image below almost got me. I found it attached to my lens cap after kneeling down in the damp moss to take a shot of some mushrooms. Even trying to get it off my lens cap was hard work, but car keys have more uses than one
I never thought I would say this but, after getting back and looking at this thing in the photo, magnified greatly, they are quite an interesting looking creature.