OMG wow that is terrifying!!!!!!!!! I had no idea leaches were so bad there!!!!!!!!! I was picturing pristine crystal clear ice cold mountain waters LOLThankfully, even though some of the places I've been look scary, there's really nothing here to be scared of. We don't even have venomous snakes here. I think besides the usual things to be scared of (like ticks), the most scary thing is the leaches (which we call "blood suckers"). Down Southern and Central Maine, they're not really a concern, but you go North, they turn into one real quick. In some of the lakes I camp at, they can get up to a few inches long (big enough for you to make out the little orange spots on their backs), and will chase you to shore. In some spots, they'll cover the bottom of your boat so much that the bottom of your boat will be black.
On those things, I can typically tell where they're going to be and where they're not (some will come up to the shoreline and wait for you to come in if they smell you near), so I haven't had one on me for years. One time though, when I was a kid, one completely wrapped itself around my wrist like a black bracelet, lol.