What do a leech and a hedgehog have in common? Both prick/stab/stick into you, apparently. One Swedish word for this is igel, so leech = igel (or blodigel); hedgehog = igelkott. Igel is an unusual term; the only other related words Norstedts has are hästigel (horse leech), igelknopp (burr-reed), and igelkottsunge (young hedgehog). The usual verb to use for prick/stab/stick into is sticka. The -kott in igelkott is also an unusual usage: it derives from kotte, which now means (pine)cone, but originally meant little clump.
The actual prickly bit of a hedgehog is a tagg, also found in taggtråd (barbed wire, literally spike thread).
Other prickly animals are the piggsvin (porcupine, literally quill pig) and the myrpiggsvin (echidna, literally ant quill pig).