Can a rabbit die if it has parasites?

Yes, a rabbit can die if it has parasites. Some parasites are relatively harmless, but others are serious problems and, if not treated by a vet, the rabbit will eventually die - either from the parasite infestation itself, or from other health problems that result when the parasite infestation isn't treated by a vet. If your rabbit has parasites, you should bring it to an experienced "rabbit savvy" vet as soon as possible. See the related questions and the link below for more information.