Our fields have deer that go through them, and who bring in ticks at a prodigious rate. I’ve pulled up to 30 ticks off one of my ponies in an evening at peak season and the dogs get quite a few too.
And when camping on the Southwest Coast Path one evening, I turned on the light to see dozens of them climbing up the inside of the tent wall! Didn’t get much sleep after that.
Despite all that, I’ve never knowingly been bitten by one, or leeches, although I do get bitten by fleas now and then.