How Cats Get Intestinal Worms

There are several types of intestinal worms that affect cats. Intestinal worms are parasites that attach themselves to the cat's intestinal lining and thrive on nutrients in the cat's body. The symptoms of worm infection differ in every cat and the most common signs are diarrhea, weight loss and vomiting. Although cat worm medication can effectively kill and control the growth of worms in different life stages, it's important to understand how cats contract intestinal worms, in order to prevent future infection.

Common intestinal worms in cats are:

  • Tapeworms
  • Roundworms
  • Hookworms
  • Whip worms
  • Tapeworms

Fleas are the most common carriers of tapeworm infections. Fleas ingest tapeworm eggs that grow into immature tapeworms inside an adult flea. Cats that regularly groom themselves may accidentally ingest infected fleas. Once the flea is ingested, the immature tapeworm develops into an adult tapeworm and attaches itself to the pet's intestinal lining. Adult worms are capable of reproduction and multiplication. Tapeworms often release segments that are visible in the feces of cats suffering from the infection.


The two types of roundworms that infect cats and kittens are Toxocara cati and the Toxascaris leonina. The mother cat (queen) is capable of passing the infection to kittens through her milk. Cats also become infected with roundworms by ingesting worm eggs from contaminated sources such as soil or plants. Roundworm eggs that are present in the environment are easily carried by pests like rodents. Cats can thus contract roundworms by ingesting infected rodents.


Hookworms are parasites that live in the small intestines of pets. The types of hookworms that infect cats are the anycylostoma ceylanicum and the ancylostoma tubaeforme. Hookworm larvae, hatch from hookworm eggs and exist in the environment for several months. Cats contract hookworms due to the ingestion of contaminated water and soil or through skin penetration. Hookworm larvae burrow through the cats skin and migrate to the intestine to mature and multiply. Kittens can also get hookworm infection through the mother's milk.


Cats become infected with whipworms after ingesting water or food that contains whipworm eggs. Once the whipworm eggs are swallowed, they hatch and develop into adult whipworms within 3 months. Adult whipworms attach themselves to the intestinal wall in cats and feed on their blood. The diagnosis of feline whipworm has to be accurate as cats that ingest rodents or mice are known to pass parasite eggs that look similar to whipworm eggs. Although whipworm infection in cats is rare, the worms exist in small numbers and cats may not necessarily exhibit any symptoms of infection.

Parasite Prevention

The treatment for pet worms is based on the type of worm infection present. Several pet owners prefer to give their pets monthly preventive tablets that reduce the risk of parasite infections. Since pets mostly contract infections from contaminated sources, it's best to prevent cats from roaming outdoors. Adequate flea control is also necessary.

Pet owners should conduct fecal exams twice a year to rule out parasite infections. Clean environments and regular grooming is also beneficial in the long run.