5 Gross Kitty Parasites You Should Know About


I admit it: Sometimes I get on a TV show kick and I just have to watch episode after episode until I’m done with every single one offered by my favorite streaming video service. My most recent vice is Monsters Inside Me, a show about people who get really gross parasitic infections, so I thought, “Hey, why not inflict this disgusting-ness on my readers here at Catster?” Check out these nasty, gross critters that can infest your furry friend.

1. Coccidia

Coccidia is a blanket term for several protozoan (one-celled) parasites that infect cats’ intestines. The most common symptom of infection is watery, mucusy diarrhea. If the infection progresses, you’ll see bloody diarrhea, inability to control defecation, lethargy, vomiting, dehydration and weight loss. Coccidiosis, the disease caused by the parasite, can be fatal to kittens because of their less-developed immune systems and susceptibility to complications of dehydration. Diagnosis is done through examining a stool sample, and treatment consists of sulfa drugs and fluid therapy to reverse dehydration.

2. Giardia

Giardia are another species of protozoan parasites, which are usually contracted from drinking from an infected water source. The Giardia species that infects cats is not the same species that infects humans. Infected cats often pass huge volumes of wretchedly foul-smelling diarrhea. These episodes can be intermittent or persistent, and may be accompanied by weight loss. Adult cats can usually fight off a giardia infection, but young adults and kittens aren’t so fortunate. Giardiasis is diagnosed by finding the protozoa or its cysts in a fecal sample, or through antibodies found in a blood test. The infection is treated with a course of metronidazole.

3. Heartworms

We usually think of heartworms as a dog thing, but cats can be infected too. Although the worms don’t reproduce well in the cat, the larvae do travel to the lungs where they can cause severe problems, ranging from asthma-like symptoms to congestive heart failure. Cats can even just drop dead from a heartworm infection if one of the worms dies. There is no approved treatment for heartworms in cats, so the best thing you can do is give your cat regular preventive treatment as directed by your vet. For more information on heartworm infection in cats, check out this article.

4. Botflies

Flies of the genus Cuterebra are found all around North America, and are obligatory parasites of rodents and rabbits, two favorite foods of outdoor cats. A cat is infected when it brushes against a blade of grass where a botfly larva is hanging out. The larvae then migrates to the nearest orifice (nose, mouth, anus, ear, etc.), through internal tissues and ultimately make its way to just below the skin, where it makes a little home and grows until the mature maggots drop out of the skin and start the cycle all over again. The most common sign of botfly infection is a lump, or “warble,” beneath the skin, but respiratory and neurological symptoms can develop if the larva migrates through the lungs or the central nervous system, and lesions can form in the eye if the botfly takes up residence there. If your cat is infected, do not attempt to remove a botfly larva yourself! If the larva breaks, it can cause an anaphylactic reaction that could lead to death. Your vet can remove it safely and give your cat medications to kill any other larva still migrating inside your cat’s body.

5. Hookworms

Hookworms are little worms that live in your cat’s intestines and feed off his blood. The feeding, and the intestinal bleeding it causes, can lead to severe anemia, especially in kittens. The nasty little critters get into your cat by burrowing into the skin of your cat’s paw pads or when your cat licks the larvae off in the process of cleaning himself. The rate of hookworm infection in kittens is very high, so they should be treated every two weeks from ages three to nine weeks. Nursing mom-cats should also be treated. Several heartworm medications also kill hookworms, so if your cat is on a heartworm preventive, she’s at less risk of infection.

So, have I grossed you out enough? I’ve certainly grossed myself out — it’s going to be a long time before I’ll be tempted by spaghetti or rice noodles, that’s for sure!

Has your cat ever been infected by one of these parasites? How did your vet treat the infection? Have there been any long-term consequences for your cat? Please share your thoughts in the comments.

About JaneA Kelley: Punk-rock cat mom, science nerd, animal shelter volunteer, professional cat sitter, and all-around geek with a passion for bad puns, intelligent conversation, and role-play adventure games. She gratefully and gracefully accepts her status as chief cat slave for her family of feline bloggers, who have been writing their award-winning cat advice blog, Paws and Effect, since 2003.

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