What Kind Of Worms Do Cats Get?

What Kind Of Worms Do Cats Get
Image: istockphoto.com / Tetiana_Chudovska

Have you noticed your cat dragging her bottom along the carpet or floor lately?  Have you observed that she lost weight, has a bloated belly and coarse fur? Chances are your cat may be infested with worms. Parasitic infections are quite common among cats especially if you allow your cat to go outdoors. 

What kind of worms do cats get?

The common kind of worms that usually infect cats include the following:

1. Roundworms 

Roundworms or Toxascaris leonina and Toxocara cati affect most cats and kittens and are considered the most common intestinal parasites among felines.  These worms are three to five inches long and live in a cat’s intestines and eat food ingested by the host. Fertile eggs are passed through the feces by adult female worms and take several weeks to develop to the larval stage.  

Cats are infected with Toxocara cati by ingesting eggs or infected rodents and kittens may be infected through an infected mama cat’s milk. Toxascaris leonina cannot pass through a cat’s milk but is usually contracted by ingesting infective eggs in contaminated soil or larvae of infected rodents. Cats with these worms may develop anemia and infection may be minimized by not allowing your cat to go outdoors and by reducing exposure to feces of infected animals. Affected kittens may experience constipation, vomiting and loss of appetite. 

These worms may infect humans and can cause damage to the eyes and organs called visceral larval migrans and ocular larval migrans. Children may be seriously affected and infection may be prevented by proper handwashing and not allowing kids to play in areas that may have contaminated soil. 

2. Hookworms

Hookworms or Ancylostoma tubaeforme and Ancylostoma braziliense, are slender and thread-like worms that are half-inch in length which makes them invisible in an infected cat’s feces.  These worms have a long lifespan, they attach themselves to the lining of the intestine’s walls and feed on the blood of their host. Cats are usually infected by their larvae through the skin or when ingested if cats come in contact with contaminated soil. Once larvae enter the cat’s system they migrate to the lungs and intestines where they develop into adult worms. 

Mild symptoms may include diarrhea and weight loss but severe cases may lead to anemia due to blood loss. Your cat’s poop may appear black and tarry due to digested blood. Hookworm larvae may also penetrate human skin when people are exposed to contaminated soil and may cause itchiness, irritation and track-like lesions. 

3. Heartworms 

Both indoor and outdoor cats are at risk from heartworms but they are not as susceptible to infection as dogs. They may get heartworms or Dirofilaria immitis if they are bitten by an infected mosquito. These worms inhabit the heart or adjacent large blood vessels of cats and female worms are around 14 inches long while males are half the size of females. However, these worms do not thrive well in a cat’s body since cats are not natural hosts of heartworms. 

It takes around eight months for infective larvae to mature into adult heartworms but it is harder to detect heartworms in cats compared to dogs. Vets usually use two types of blood tests to confirm an infestation as well as X-rays and a heart ultrasound. 

4. Tapeworms

Image: istockphoto.com / Sinhyu

Tapeworms or Dipylidium caninum have flat bodies that resemble tape or ribbon. They need a host such as a flea, bird, rat or rabbit to complete their life cycle. Your cat does not get these worms directly from another cat or dog but by eating infected prey or fleas while grooming themselves. Fleas, rodents and other prey are infected by eating tapeworm eggs in the environment. 

These worms are most common among outdoor cats that hunt prey and kittens may also be infected if they eat raw prey. Heavy infections of tapeworms may cause intestinal blockage. While medication is successful at treating infections, reinfection may still occur and a good alternative is to control flea and rodent populations to reduce tapeworm infection.

5. Stomach worms 

Stomach worms or Ollanulus tricuspis and Physaloptera inhabit the stomach of cats. Felines that are mostly infected are free-roaming or outdoor cats and those that live in multiple-cat facilities.  Cats become infected by eating the contaminated vomit of another cat.  The most effective way to curb infection is to avoid exposure to cat vomit. Diagnosis is usually through microscopic detection of eggs in the stool or vomit.  

6. Lungworms 

Lungworms that affect cats are called Aelurostrongylus obstrusus and Capillaria aerophilus and both can cause lung damage. Cats that are most at risk are those that go outdoors and may become infected when they drink water or eat prey that is infected with worm larvae. Adult worms develop in the lungs where they lay eggs within 40 days which are coughed up or passed in the poop and eaten by birds, rodents or snails. 

Coughing fits, lethargy and loss of interest in playtime among cats are common signs of the presence of lungworms. These worms are usually diagnosed through blood tests, X-rays, bronchoscopy and fecal tests. 

7. Bladder worms 

Bladder worms or Capillaria feliscati, Capillaria plica and Capillaria aerophilus are small worms that live in the bladder but may also inhabit the kidneys, lungs and trachea. Cats are usually infected through the environment and when they come in contact with infected urine.  

8. Whipworms 

Whipworms or Trichuris campanula and Trichuris serrata affect cats but are more common among dogs. These worms find their way to a cat’s body once they are ingested as they live in the soil, food, or water. These worms usually inhabit the intestines and eggs usually take three months to hatch. To avoid infestation, keep your cat indoors and always keep the litter box clean and sanitized. 

What are the common symptoms of worms in cats?

What are the common symptoms of worms in cats
Image: istockphoto.com / Sinhyu

These are the common symptoms and signs that your cat has worms:

  • unexplained weight loss  
  • distented and bloated stomach
  • coarse and unhealthy fur 
  • bloody, tarry stool and diarrhea 
  • changes in your cat’s bowel habits 
  • visible traces of worms in poop
  • she is exhibiting unusual behavior like lethargy and dragging her bottom on the carpet or floor 
  • constipation 
  • skin lesions 
  • constant coughing 
  • vomiting and throwing up worms 
  • has difficulty breathing 

Severe symptoms may include the following:

  • dehydration
  • weakness 
  • pale gums and lips 
  • low blood pressure or anemia
  • shock 

If you suspect that your cat has worms, consult your veterinarian at once. Your vet can accurately diagnose worm infestation through a series of tests so that the proper medication may be given.  You may also check out an earlier article on how much does it cost to deworm a cat for more information. 


Cats are fastidious animals but they are still prone to parasitic infestations especially if they are allowed to roam the outdoors and hunt prey.  The common worms that cats usually get are hookworms, tapeworms, roundworms, heartworms, and lungworms. These worms may multiply into large numbers if not treated promptly and may even be life-threatening for cats. It is best to keep your cat indoors to prevent exposure to contaminated surroundings and prey. Most importantly, consult your vet if you suspect that your cat has worms so that it gets proper treatment as quickly as possible.