Internal Parasites in Cats This handout is designed to give you
an overview of some of the internal parasites that can infect
your cat. For more detailed information, refer to our separate
information sheets on roundworms, hookworms, whipworms,
tapeworms and heartworms. Are there different sorts of internal
parasites or worms? There are several types of internal
parasites that cause problems in cats. These include nematodes
or roundworms, of which Toxocara cati, Toxascaris leonina
(intestinal roundworm) and Dirofilaria immitis (heartworm) are
the main examples, and cestodes or tapeworms of which Dipylidium
caninum, Taenia species and Echinococcus species are important
examples. Ancylostoma species (hookworms) are also common
internal parasites in many parts of the United States and
Canada. Are these infections serious in the cat? Intestinal
worms can be a serious problem in young kittens. Hookworms can
cause anemia and roundworms can lead to poor growth and
development. Intestinal parasites are only occasiona