A Short Guide To Common Parasites In Cats

Lisa Selvaggio
by Lisa Selvaggio
What’s going on with your kitty’s health? Here’s our need-to-know list of common parasites in cats.

Both external and internal parasites can affect a cat of any age. And when a pet has a large parasitic burden, he can experience other health complications, such as digestive upset and anemia. Therefore, it’s imperative that you target a parasitic infection and get your cat treatment as soon as possible. With the right veterinary exams and tests, you can rest assured that your kitty is free of all parasites, including the ones that can be transferred to humans.

Below are just a few of the many common parasites in cats.


Giardia are microscopic one-celled organisms that attack the small intestine of felines, but they can also infect humans and canines. Ingestion of contaminated water or the contaminated feces of another animal with giardia are common modes of transmission. Once infected, a cat may experience digestive issues that include intermittent or continuous diarrhea, gas, and vomiting. Sometimes, however, no symptoms are present. Without the right medication and a hygienic environment, giardia can be difficult to eliminate and your animal can become reinfected or infect other pets in the household. An ELISA fecal exam is a good way to diagnose giardia because it does not always shed in the feces and, therefore, may be missed by regular fecal exams.

Related: Two Infectious Cat Diseases You Should Know About


Roundworms are the most common parasites in cats, and kittens often become infected through their mother’s milk. When a cat is infected with a large number of roundworms, serious complications can occur because these worms steal vital nutrients from the host and can even cause a blockage. Kittens, in particular, are vulnerable to these complications. Symptoms of infection include diarrhea and vomiting, and worms that look like spaghetti may be passed from the body. Bringing a stool sample to your vet for testing will determine whether or not your cat is infected.

Related: Which Feline Vaccinations Are Really Necessary?

Ear Mites

Ear mites survive by eating the wax and oils produced by your cat’s ears. There are different types of ear mites that can infect felines, but they will all produce a characteristic discharge that looks like coffee grounds. These parasites will also result in inflammation and irritation, so you may notice your cat scratching his ears or shaking his head excessively. Odor emanating from the ears, as well as scabs or obstructions in the ears, are also signs of infestation. When left untreated, these parasites can cause even more serious infections, hearing loss, and aural hematomas. Have your cat’s ears examined by your vet to determine if ear mites are a problem and to get appropriate medicine to get rid of them promptly.


Yet another intestinal parasite that steals nutrients from its host is the tapeworm. The difference between tapeworms and roundworms, though, is the fact that tapeworms will actually attach themselves to the intestinal wall. These parasites are usually transferred via ingestion of fleas, so making sure your cat doesn’t come into contact with fleas is an important preventative step. Severe infections can lead to malnutrition, and these worms can also cause anal irritation and itching. When passed through the stool, they look like grains of rice that may attach to the fur around the anus. Tapeworms are more dangerous to kittens than adult cats, but they should be eliminated with the right medications no matter what.


Fleas are external parasites that bite their hosts to feast on blood. An infestation is even more dangerous to a small kitten, who can quickly become anemic. Kittens who have a lot of fleas, therefore, are at risk of dying from the loss of blood. In addition, fleas can transmit other infections and parasites, so getting rid of them quickly is important, no matter how old your cat is. To determine if your cat has fleas, you can use a flea comb to catch live fleas or to look for flea dirt. In the event that your pet is infected, there are a variety of medications you can use, from oral to topical treatments, that will kill the parasites. But you also need to be sure you thoroughly clean your cat’s environment to prevent reinfection.

Lisa Selvaggio
Lisa Selvaggio

Lisa Selvaggio is a freelance writer and editor, and our resident cats-pert, with certifications in pet nutrition and pet first aid. She enjoys producing content that helps people understand animals better so they can give their pets a safe and happy home.

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