What are heartworms and how do animals get them?
The heartworm is a parasitic roundworm (Dirofilaria immitis) that is spread from host to host through the bites of mosquitoes. The heartworm is a type of filaria, a small thread-like worm. The definitive host is the dog but it can also infect cats, wolves, coyotes, foxes and other animals, such as ferrets, sea lions and even, under very rare circumstances, humans. The parasite is commonly called “heartworm” because the adult reproductive stage of its life cycle resides primarily in the right atrium of its host where it can live for many years.
