Feline Parasites

 In Medical News

Feline Parasites

Spring is finally here and the weather couldn’t be more perfect. We are spending more time outside and with our windows open. Because of this, we also see a rise in feline parasites! Parasites can affect cats that spend all their time indoors as well as cats that go outside. Parasites can come in through screens, open windows, on our shoes, or even come in potting soil used for house plants.

There are three classes of parasites: ectoparasites (parasites that live on the cat), feline heartworm, and intestinal parasites. Most can be prevented and treated but it is important to be proactive. Many of the parasites that cats get can be transmitted to people too. Protecting your cat also protects everyone in your family.


The most common feline ectoparasite is the flea. Fleas can cause numerous symptoms in the cat including an itchy/scabby rash, hair loss, overgrooming and flea allergy dermatitis. Some cats will have no symptoms at all. Fleas can also transmit many bacterial and parasitic diseases to cats. Cats with fleas commonly get tapeworms since they are carried by the flea and are ingested when the cat grooms. Severe flea infestations can lead to severe anemia and even death, especially in kittens. In people fleas have been shown to cause cat scratch disease, tapeworms, murine typhus, and flea-borne typhus. People can be bitten by fleas and develop an allergic reaction to the bites. Once a flea infestation is established in your home it can take months to eradicate it. We often see indoor cats infected with fleas, so it is important to protect them as well as the cats who go outside. Oral and topical flea control treatment is readily available and very effective.

Ticks are usually found on pets that go outside, but indoor cats can become infected if a tick is brought into the home from a person or another pet. Ticks carry many diseases that can affect cats, dogs and people. Ticks are active throughout the year, so it is important to use tick control year round.

Lice can be found on cats, but usually only older/sick cats get infected. Lice are host specific, so it is not a risk to people. If infected, cats can show signs, including itchy skin, hair loss, restlessness, and scratching. Lice are easily treated with most flea control products.

We often get asked about bed bugs and cats. Bed bugs primarily feed on people and our pets are not the source of the infestation. In heavy infestations they may feed on our pets. It is very important to get an exterminator to help you get rid of bed bugs from your home.

Skin and ear mites can also be found on cats. Ear mites are very common and can be spread to other pets in the house. Your cat may be excessively scratching at their ears and you may see a brown discharge in the ears. Skin mites are less common, but can cause crusty lesions, itchiness and hair loss. Some mites can be spread to people and can cause an itchy rash on your skin. Mites can be difficult to diagnose in cats since they are fastidious groomers. Cats can ingest the mites while grooming making it hard to find them on the skin. Some infections can be diagnosed with a fecal sample looking for ingested mites. Most mites can be prevented and treated with some common topical flea control products.


Cats are infected with heartworms when they are bitten by a mosquito carrying the disease. Because mosquitos can come inside our homes, we see heartworm disease in cats who spend 100% of their time indoors. Unfortunately, if a cat develops adult heartworms, we do not have good treatment options. Their disease can be fatal. Even if cats are infected with heartworm and they do not develop adult heartworms, the initial infection can cause asthma like symptoms in the cat (Heartworm Associated Respiratory Distress). Heartworm disease is difficult to diagnose in many cases, so prevention is very important for all cats year round.

Intestinal Parasites

Intestinal parasites are very common, even in indoor pets. Often you will not see the “worms” because the cats are shedding microscopic eggs. Because many of the intestinal parasites can be spread to people (especially children, elderly and immunocompromised people), it is recommended that kittens have 4 fecal parasite screens in the first year, then adults should be screened twice a year (www.capcvet.org). We recommend you bring a fecal sample with you for each cat at their annual exam and anytime they are vomiting or have diarrhea. Some of the most common intestinal parasites we see are roundworms, hookworms, tapeworms, coccidia and giardia. Some topical flea control products will also treat and protect your cat from roundworm and hookworm infections. Many cats will not have any symptoms when they are infected, so frequent screening is important; however, some cats will have vomiting or diarrhea and kittens may have a bloated belly.

Roundworms are extremely common in cats. People infected with roundworms can have neurologic disease, enlarged organs (visceral larva migrans), on even eye involvement that can lead to blindness in children. We see hookworms less commonly in cats, but these parasites can migrate though our skin and cause a self-limiting severely itchy rash (cutaneous larva migrans). It is unsure if giardia can be transmitted from pets to people, but if you are in contact with an infected pet and develop gastrointestinal symptoms, it is advised you seek medical attention.

Testing, Control & Treatment

Feline ectoparasites are often found through direct examination. However, since cats are good groomers the parasites can often be missed. Fleas can be found with a simple flea comb; however, lice and mites need to be examined under a microscope after collecting some samples of skin and fur. If your cat has any of the symptoms associated with ectoparasites, but no bugs were found on our exam we often will treat for the suspected parasite to see if the symptoms resolve. Fleas, lice, and some mites can be treated and prevented with the use of Revolution, a topical once a month anti-parasitic. Revolution is not labeled for ticks in the cat, but it is guaranteed by Zoetis to cover ticks.

Heartworm testing is difficult. We have a blood test that can screen for antibodies and antigen, however it is common to get a negative result even if the cat has an infection. Sometimes x-rays, or even an ultrasound of the heart is needed to help confirm the diagnosis; however, many cats aren’t diagnosed until after death with a necropsy. Once a month Revolution can protect your cat from Heartworm disease. Revolution is also recommended if your cat has heartworm to help prevent re-infection with more heartworms.

Fecal parasite screening is recommended annually for all cats. Kittens and outdoor cats should be screened more frequently. Litterboxes should be scooped and cleaned often. Be sure to wear gloves or wash your hands immediately after handling the litter. Again, monthly Revolution can prevent and treat roundworms and hookworms. We also use dewormers and antibiotics to treat some of the intestinal parasites.
As you can read, Revolution doesn’t treat everything but it covers a lot of the parasites we can find in or on your cat. This is why we recommend monthly, year round Revolution for all cats!

As you can read, Revolution doesn’t treat everything but it covers a lot of the parasites we can find in or on your cat. This is why we recommend monthly, year round Revolution for all cats!


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422 East Baltimore Avenue • Media, PA 19063
Phone: 610-627-2287 | Fax: 610-627-2289 | Email: info@mediacatvet.com

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