Strange crayfish disease?

[robthetenor]

My crayfish came with some little worm looking things, they're about 2 mm long and can freely love about it's body. They sometimes hang on by their heads and just stick up like a thick hair. The underside of the crayfish... is weird... if you look really carefully there are little clusters of black spots, that look kind of like eggs. They're very small, but visible. It's some kind of yabby by the way... anyways I've tried everything nothing seems to work. I've used anti flat worm medication, that didn't seen to even stun them. He is acting happy as far as I can tell, very aggressive and hungry, eats anything he can get. Currently in a 55 gallon, he was given a salt bath and lived in a 5 gallon for a while, seemed happy there too... I am pretty stumped, any suggestions? Also before you recommend common crayfish worms, keep in mind that they are very very small and appear to have forked tails. They are also white in colour. Please help me, this probably isn't very well articulated but I've spent the entire night reading and I am really worried : /