Yes, they have some medical applications, such as causing blood to ooze continuously so that the body's own blood supply will eventually take over and a severely damaged limb can heal and survive.
this is just my guess, it may not be that helpful, but i think leaches, if that's how you spell it, it sticks on your flesh and sucks your blood, it hurts, i learned it from a movie. lol
No they do not
No, leaches are from Phylum Annelida and Class Hirudinea, which is completely separate from Phylum Mollusca.
go on the internetfind out what you needgo buy the stuff you needgo kill the leaches
No
leaches
you could drain the pool, but if you don't want to drain your pool, you could get a pool skimmer and get all of the leaches out of your pool and then carry the leaches to a near by sewer, or a murky pond/lake/river.
No, they are invertebrate creatures.
Yes, blood.
yes
yes
They thought there were "vapers" in the blood so they used leaches to remove them.