Unfortunately, cats are susceptible to lots of different infestations. That’s especially the case if your cat goes outdoors a lot and interacts with other cats, which is how most parasites are caught.
What parasites infest cats? The most common are fleas and ticks. Cheyletiellosis mites, ear mites, heartworm, hookworm and whipworm are less common but even worse for your cat’s health. Treatment varies based on the kind of parasite infesting your cat. Some can be killed with sprays, while other parasites require an expensive vet’s visit.
Whatever you do, don’t put off treatment. Fleas, ticks and mites don’t go away on their own. You have to kill them—whether with a commercial spray, homemade flea spray or a vet visit.
Parasites and Cats
Cat Infestations: Fleas & Ticks
Alright then, starting from the top with the most common cat infestations: fleas an ticks. Fleas, as you probably know, are extremely common. According to the University of Florida, fleas are small, reddish-brown insects which live in the fur of dogs and cats. They live on blood, and depend upon biting animals to survive. Although fleas can’t fly, they can jump long distances and tall heights. That differentiates them from ticks, which are less mobile. For this reason, fleas are easily able to travel from one pet to another.
Almost all cats that are allowed outdoors will catch fleas or ticks at some point. According to a study in the Caspian Journal of Internal Medicine, fleas can even travel and live on humans (though it’s rarer). So, even your indoor kitties aren’t safe! You could pick fleas up from the outside, and bring them home.
Signs of Fleas In Cats
Fleas and ticks, like most cat parasites and parasites in general, feed on blood. They live in your cat’s fur, and bite to draw blood. These bites can be itchy and even painful for your poor kitty. If you notice your cat scratching or over-grooming, fleas may be the culprit.
According to research in the Scientific World Journal, this is how to spot a flea infestation, and pick up on signs of fleas in cats:
- Invest in a flea-comb, and run it through your cat’s fur. (Normal combs are ineffective, as the gaps between teeth are too wide.) Then, examine the comb.
- Look for “flea dirt” (feces). This will appear as small, black pepper-like specks. To be certain it’s flea dirt, put a few pieces onto a damp paper towel. If it turns red, it’s flea dirt.
- Of course, keep an eye out for the fleas themselves. However, they’re very small – only about 1/16 inch – and move fast, so they’re hard to catch with the comb.
Sometimes, you may also be able to see raised red bite marks on your cat’s skin. These are the skin’s natural reaction: a small inflammation, which is intended to make it harder for any infection or further tissue damage to take place. You’ll get the same raised bumps if you’re bitten by fleas, too.
How to Get Rid of Fleas and Ticks in Cats
There are many different types of flea treatments available. The most common types are flea sprays, flea collars, and topical (“spot-on”) treatments. Different brands contain different active ingredients. How do you know which is the best?
Fortunately, there’s a lot of scientific research on flea control in cats. Some of the most effective insecticides for flea control are:
- Imidacloprid. This is an adulticide (it kills adult fleas). A study in the American Journal of Veterinary Research found imidacloprid to be consistently effective at preventing and eradicating flea infestations. Popular products that use imadicloprid include Advantage II (a spot-on treatment) and Seresto (a flea collar).
- Pyriproxyfen. This is an “insect growth regulator”, which inhibits the development of fleas, rather than killing adult ones. A study in the Veterinary Record found pyriproxyfen significantly effective for inhibiting flea reproduction. Advantage II contains pyriproxyfen alongside imidacloprid.
- Selamectin. This is another insecticide which both kills adult fleas, and prevents eggs from hatching. According to Veterinary Parasitology, selamectin is highly effective against fleas for at least 27 days after application. It comes under the brand names Revolution and Stronghold. You can also use it preventatively, to stop your cat catching fleas in the first place.
Cat Infestations: Cheyletiellosis in Cats
Cheyletiella mites live on your cat’s skin. They can also affect dogs and rabbits, too. They’re absolutely minute; even smaller than fleas. Their distinguishing features are large, claw-like mouth parts. Whilst they prefer to live on furrier mammals, the mites can also live on humans. So if you and your cat are sharing an itchy rash, these mites may be the culprit of the irritation.
How to Spot Cheyletiellosis in Cats
Cheyletiellosis, aside from being hard to spell and pronounce, are distressing cat infestations for your pet. Their presence will cause irritation, dandruff and itchiness. It’s also known as walking dandruff, because it causes a mild form of dermatitis. In severe cases, it may even cause hair loss.
A paper in the Canadian Veterinary Journal detailed a case study. They described how the affected cat’s coat was actually remarkably clean (which they thought was a result of the owner trying to tackle the infestation on their own!) However, the cat had been consistently scratching the same area for a number of weeks, and small sores were present on the cat’s head and neck.
On closer inspection, they found a kind of skin-scaling called pityriasis. This is a kind of rash, where the skin is discolored in patches. No mites were easily visible; Cheylietella mites are microscopic in size. They’re also well-disguised, and appear to look like small flakes of dandruff.
How to Get Rid of Cheyletiellosis in Cats
Because Cheyletiella mites are relatively rare compared to fleas, there aren’t as many treatments available. However, there are a couple:
- Selamectin. Selamectin is branded as Revolution and Stronghold; it’s a common treatment that’s used to tackle ear mites, heartworms, fleas, ticks and more. Another study in the Canadian Veterinary Journal found that it works against Cheyletiella mites too.
- Ivermectin. Ivermectin is sold under the brand names Heartgard and Sklice, Stromectol, and also as a generic prescription drug. It’s very effective against Cheyletiella at normal doses.
Cat Infestations: Ear Mites
Whilst ear mites are not as common as fleas or worms, the tiny parasites are still prevalent. They live out their 3-week life cycle inside of the ear canal. As you can imagine this will mean severe irritation and discomfort for your cat. There main species of ear mite is Otodectes cynotis, although there are others that affect other animals like rabbits.
Ear mites are virtually undetectable to the naked eye, however, you may be able to see the dirt they leave behind in the ear canal. They spread rapidly, after even the faintest contact. That’s because they’re surface mites: they don’t burrow into the skin, they simply sit on top of it, and in the fur.
To be specific, they cause otodectic otitis, a form of mange. This comes in the form of inflammation in the middle ear and inflammation in the external ear canal in cats. These mites are responsible for more than 50% of cases.
How to Spot Ear Mites in Cats
Since ear mites are so small, it’s very difficult to see them with the naked eye. However, there are a number of symptoms, each of which—unsurprisingly—involves the ears.
- Shaking, rubbing and scratching the ears
- Scabs around the ear that are having trouble healing
- Inflammation of the ear canal, both inside and out
- A strong, foul odor in and around the ears
- A dark brown or black waxy buildup in the ear
Ear mites as cat infestations are more common in kittens than in adults. They’re also more common in cats who are allowed outdoors.
How to Treat Ear Mites in Cats
The best way to diagnose and treat ear mites is by visiting your veterinarian. The symptoms of ear mites can look similar to other kinds of ear problems and infections. So, rather than diagnosing them yourself, it’s best to leave it to a professional.
If your cat has been diagnosed with ear mites, there are some things you can do at home to help.
- Purchase a cat ear cleaner. This comes in the form of a liquid, usually with a dropper-like applicator. Make sure to buy a cleaner specifically made for cats, and not humans.
- Apply the cleaner as per the instructions. Gently massage your cat’s ears at the base to spread it around. Then, use a cotton ball (or your finger wrapped in gauze) to clean away any loosened wax and debris.
- Purchase ear mite drops to kill the mites. Your veterinarian may recommend or prescribe a specific type. If not, various brands are available online. Follow the provided instructions carefully. Make sure to continue the treatment for as long as your veterinarian recommends.
- Use a topical Selamectin treatment, such as Revolution, to prevent ear mites from returning. According to a study in Veterinary Parasitology, selamectin is 100% effective against ear mites.
Cat Infestations: Heartworm
Of all the cat infestations out there, heartworm (dirofilaria immitis) is probably the scariest. Unlike other cat parasites such as fleas and ear mites, heartworm can actually be fatal in cats. This is because the parasite actually infests the cardiovascular system, as its name suggests. Heartworm larvae infest the muscles and blood vessels, while adults reside in the pulmonary artery and right side of the heart.
For a cat to contract heartworm, it must be bitten by a mosquito. Heartworm larvae live inside mosquitos, waiting to be transferred to a host animal. Once the larvae make their way under the skin, the animal is infected. Sometimes, a heartworm infection can cause a lung disease called Heartworm Associated Respiratory Disease.
Fortunately, heartworm is not very common in cats. Whereas dogs are a natural host, most heartworm larvae can’t survive inside a cat’s body. According to the American Animal Hospital Association, the infection rate in cats is 1 – 5% of that in dogs. That being said, it is still possible, so be sure to watch out for symptoms.
How to Diagnose Heartworm in Cats
As heartworms live inside the body, you can’t see them. Only a veterinarian can diagnose their presence in a cat’s body. However, there are some symptoms you can look out for. According to the American Heartworm Society, cats with heartworm could display:
- Rapid or labored, raspy breathing
- Weight loss and anorexia (refusing to eat)
- Malaise (generally not seeming themselves)
- Irregular heart rhythm
All of the above could be explained by other illnesses, so don’t panic if you’ve noticed any of these symptoms. However, if you have, it’s best to take your cat to a veterinarian. They may run blood tests, ultrasounds, x-rays or other tests to determine the cause.
How to Treat Heartworm in Cats
Some cases of heartworm in cats tend to resolve themselves. In cats, the majority of heartworm larvae don’t survive, and the adults aren’t likely to live very long. If your cat doesn’t seem very sick, your vet may recommend simply waiting it out. They’ll monitor your cat regularly to see how the infestation is progressing.
If your cat is very ill, there are various things your vet may prescribe to help them. Immunosuppressants, corticosteroids, electrolytes and bronchodilators can help with respiratory symptoms.
Unfortunately, there is no medication for killing adult heartworms. The only option, if the infestation is severe, is to surgically remove the worms. However, this can be very dangerous.
Luckily, it’s easy to prevent heartworm in the first place. Topical selamectin treatments – such as Revolution – are 100% effective at preventing the heartworm in cats. Even if an infected mosquito bites them, the selamectin will kill the heartworm larvae before they have a chance to grow into adults. Ivermectin is equally effective. It’s available under brands such as Heartgard.
Cat Infestations: Hookworm and Whipworm
Hookworms and whipworms are parasitical worms that live inside the gastrointestinal tract (your cat’s gut). Though they’re different, their symptoms, diagnosis and treatment is almost identical. They’re very similar cat infestations, and so we’re including them both in this section.
Hookworms and whipworms feed on the blood and intestinal tissue of the host animal. They’re called hookworms because they have tiny hook-like mouth parts, which attach onto the intestinal wall.
Infected cats pass hookworm eggs in their feces. These eggs then hatch into hookworm larvae, which live in the soil outside. When another cat walks over the soil, the larvae attach to the cat’s feet. The cat swallows the larvae when they groom their feet – and then they’re infected. Cats can catch whipworm in the same way, but they can also transfer through flesh. So, a cat can catch whipworms from eating an infested bird or mouse.
How to Spot Hookworm and Whipworm in Cats
Hookworm and whipworm can cause some undesirable effects. Very severe infestations can lead to compliations (especially in kittens). If left untreated, infected cats can even die.
The observable symptoms of hookworm and whipworm include:
- Blood in the stool
- Dark, tar-like stools
- Weight loss and poor appetite
- Pale gums, nostrils and lips (due to anemia caused by the hookworm)
- General malaise, or your cat not seeming well
If you suspect an infestation of hookworm or whipworm, take your cat to the vet, along with a stool sample. To make a diagnosis, the vet simply has to add the cat’s stool to water. Hookworm and whipworm eggs will float to the top and are visible under a microscope.
How to Treat Hookworm and Whipworm in Cats
Fortunately, unlike heartworm, hookworm and whipworm in cats are easily treatable.
Your vet will administer a drug called an anthelminic. This is a kind of antiparasitic which kills and expels intestinal worms from the cat’s system. These are available in various formats, including tablets or liquids. As anthelminics don’t kill larvae, your cat will need to continue the course for some time – at least three weeks.
You can also prevent hookworms from returning by administering an anthelminic regularly even when your cat is healthy. Selamectin (used by the brand Revolution) effectively treats and prevents hookworm in cats, according to a study in Veterinary Parasitology. You may have noticed that we keep bringing this one up – it’s because it’s such an effective all-round antiparasitic! There are currently no studies on its efficacy for whipworm, mainly because whipworms are quite uncommon in cats.
Thanks for stopping by and reading our guide to cat infestations today. We hope it didn’t make you itch too much! If you have cat-loving friends who may also be interested in reading our advice, please consider sharing it with them. For more information on feline health issues, check out our complete guide!
Hi! My name is Jamie Fallon. I run Catmart.net, an online cat health and cat behavior resource. If I’m not sat in front of my PC—and I usually am—then I’m either spending time with my cats or my other half… Whoever jumps on me or asks me for food first!