Cats can acquire a variety of intestinal parasites, including some that are commonly referred to as “worms.” Infestations of intestinal worms can cause a variety of symptoms. Sometimes cats demonstrate few to no outward signs of infection, and the infestation can go undetected despite being a potentially serious health problem. Some feline parasitic worms are hazards for human health as well.
Worms in Cats
Common Types of Worms in Cats
Outdoor cats and those who are routinely exposed to soil where other animals defecate are prone to worms. Kittens and cats who do not receive regular preventative health care are most at risk for developing complications associated with internal parasites.
- Roundworms are the most common internal parasites in cats. Resembling spaghetti, adult worms are three to four inches long. There are several ways cats can become infected. Nursing kittens can get roundworms from an infected mother’s milk, while adult cats can acquire them by ingesting eggs from the feces of an infected cat.
- Hookworms are much smaller than roundworms—less than an inch long—and reside primarily in the small intestine. Because they feed on an animal’s blood, hookworms can cause life-threatening anemia, especially in kittens. Hookworm eggs are passed in the stool and hatch into larvae, and a cat can become infected either through ingestion or skin contact.
- Tapeworms are long, flat, segmented parasites that range from 4 to 28 inches in length. An infestation can cause vomiting or weight loss. Cats acquire tapeworms by ingesting an intermediate host, like an infected flea or rodent. When cats are infected, tapeworm segments—actual pieces of the worm that resemble grains of rice—can often be seen on the fur around a cat’s hind end.
- Lungworms reside in the lungs of a cat. Most cats will not show any signs of having lungworms, but some can develop a cough. Snails and slugs are popular intermediate hosts of this type of parasite, but cats are usually infected after eating a bird or rodent who has ingested an intermediate host.
- Though means of transmission can vary, one of the main ways that cats get worms is through the ingestion of the feces of infected felines. Mother cats can also pass on worms to their kittens.
- Keep your cat indoors to avoid exposure to infected cats, rodents, fleas and feces.
- Make sure your home, yard and pets are flea-free.
- Practice good hygiene and wear gloves when changing cat litter or handling feces. It’s also important to frequently dispose of stool.
- Ask your veterinarian to recommend an appropriate internal parasite treatment or prevention program for your cat.
Symptoms of Worms in Cats
Symptoms differ depending on the type of parasite and the location of the infection, but some common clinical signs include:
- Worms visible in stool or segments of worm seen near anus
- Bloody stool
- Bloating or round, potbellied appearance to abdomen
- Weight loss
- Trouble breathing
If you think your cat may have worms, it’s important to bring her to a veterinarian, who can confirm the presence of worms. Avoid self-diagnosis, since worms are not always visible or identifiable
Treatment for Worms
Please don’t attempt to treat your pet yourself—your cat should be treated for the specific type of worms he has.
- Not all dewormers eradicate all types of worms. Your veterinarian will determine the type of worm(s) infestation(s) your cat has, and prescribe the best course of treatment. Your veterinarian will also be able to tell you if the dewormer should be repeated, and when.
- Not all dog medications are safe for cats.
- Some over-the-counter deworming medications can be harmful if used inappropriately.
Transmission of Worms from Cats to Humans
A large number of roundworm eggs can accumulate where cats defecate. People, especially children, who ingest such eggs can develop serious health problems, such as blindness, encephalitis and other organ damage. Treatment of blindness caused by roundworms may involve surgical removal.
Hookworm larvae can penetrate human skin and cause lesions. People can acquire tapeworms through the ingestion of an infected flea, although this is rare.