Elves are small supernatural creatures. In "The Southern Vampire Mysteries", very little is known about elves.
There is mention in the short story "Two Blondes" that Elves have very sharp teeth and that their blood is poisonous to vampires. If elf blood is ingested, it will greatly weaken and disorient a vampire for a short period of time. In "Two Blondes", Sookie shoots Rudy, a half-elf, in the face and chest but he is not mortally wounded. This implies that they are very durable supernaturals and may potentially be more dangerous than others that have been previously introduced. It also implies that they do not share the fairy susceptibility to iron.