Look up "worm bin mites ".

I think that this post has solved another mite question.

mite not have.. you never know..

ken

ps: see what i did there.. lol ...

Mites in worm bins seem to provoke a lot of discussion with some people adamant they must be eliminated and others just as adamant that they do no harm, except compete with the worms for food.
What ever poison you might apply to control these mites may also do great harm to your worms.

There are numerous types of mites found in compost, chicken bedding, worm bins. It's a mixed population and most are not animal/human issues as far as being prey.......but some are and why finding out whatcha got is wise. You can assume if they're in compost they are not after warm blood.