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My question to you guys is that, is it possible for pinworms to migrate to the thigh and survive there?
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Maybe it is not pinworms, but filarial worms or a kind of roundworms which can move to other parts of the body.
or maybe you have tried to kill the worms with a zapper or a drug or a herb and it was not powerfull enough so they moved to others parts of the body in order to avoid it.
I feel several larveas in all parts of my body, it is annoying to feel them move and bite but i don't care because they finally die.
Focus on killing the adult worms that lay eggs. Else you will never manage to get rid of it.