Cutworms are about the worst thing you can get in grass. they eat the roots, but they are not worms as such, they are the larva of the crane fly.
There are worms found in animal faeces which are not good for one, but they are not really found in the soil as such.

Agree with Owdboggy - leatherjackets (crane fly larvae) and chafer grubs would be the worst things in a lawn, and neither is dangerous to health. You may be thinking of parks, where there may be a lot of dog excrement, and if that had a particular type of worm in it, is transmissable to humans, but the worm was in the excrement, not in the soil. These days, though, there's much less dog excrement about than there used to be, poop scooping being done by most responsible dog owners.

Thanks for your comments - they answered my query.