Heartworm (Dirofilaria immitis) is a parasitic roundworm that is spread from host to host through the bites of mosquitoes. The heartworm is a type of filaria, a small thread-like worm, that causes filariasis. 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.
Attributes / relations provided by ♦1Gibson, D. I., Bray, R. A., & Harris, E. A. (Compilers) (2005). Host-Parasite Database of the Natural History Museum, London ♦2Nunn, C. L., and S. Altizer. 2005. The Global Mammal Parasite Database: An Online Resource for Infectious Disease Records in Wild Primates. Evolutionary Anthroplogy 14:1-2.