Veterinarian-written / veterinarian-approved articles for your cat.

Uncommon Feline Parasites

cat_white_layingWe don't see some of the parasites listed below in all geographic areas, or in some cases, as frequently in cats as a species. Parasites have adapted to take advantage of their cat hosts in some unusual ways, as you will read below.


These flies (Cuterebra) are normally parasites of rabbits and rodents. The fly eggs are deposited on blades of grass, and a cat out hunting can pick up the eggs as she walks past. The maggots then find a body orifice to enter and migrate throughout the body tissues, eventually producing an encysted larva or bot (warble) under the skin. Migrating larvae can also produce problems in the body systems as they migrate. Eye problems or respiratory or nervous signs may result. Usually found in late summer and early fall in the northern US, it occurs throughout most of the year in the south. Treatment is surgical removal of warbles under the skin and possibly antibiotics and anti-inflammatory medications.

Liver Flukes

Platynosomum concinnum infection occurs in cats living in tropical areas such as Hawaii and Florida . Transmission is via eating an intermediate host: frogs and lizards. Many cats infected with liver flukes show no signs, but signs can range from loss of appetite and vomiting to jaundice and diarrhea. Diagnosis is made by your veterinarian, who must rule out other causes of liver disease. Definitive diagnosis is made by performing liver biopsy with microscopic analysis of cell changes. Treatment involves fluids, proper nutrition, de-wormer, antibiotics, and anti-inflammatory medication. Prevention is possible by treating susceptible cats with a de-worming product every three months or keeping them indoors.

Lung Flukes

Intermediate hosts for lung flukes are snails and crayfish. Paragonimus kellicotti is the name of the parasite. Generally, signs reflect damage to the lung and include pneumonia. It is most commonly found along the eastern seaboard of the US, in the Great Lakes region, and in Louisiana . Diagnosis is made by your veterinarian using lung x-rays and a fecal exam. Treatment includes de-wormers and supportive care for the cough. Follow up x-rays and fecal exams should be performed to confirm treatment effectiveness.


Aleurostrongylus abstrusus is the name of the worm that colonizes the lung tissues. The larvae are produced and then swallowed and passed in the stool. The source of the infection is likely voles and mice that carry the larvae, which develop in snails. Sometimes appetite loss and cough are seen. In severe cases, breathing difficulty may develop.

Feline Lice

Lice infestations with Felicola subrostratus are uncommon. Dandruff and itchy skin are commonly noted signs. You can learn more here: "Lice in Cats."

Eye Worms

Generally a problem only in California, the Thelazia parasites irritate the eye, and sometimes surgical removal of the eye is necessary.

Stomach Worms

One might rarely note these in vomit or stool. The Physaloptera worm may cause poor hair coat, poor appetite, and sometimes vomiting. This worm irritates the stomach lining, leading to gastritis. Cats pick them up by eating insects which are carrying the larvae. Diagnosis is by endocscopic examination of the stomach and visualization and retrieval of worms. The feces may also contain eggs. The parasite is cleared with de-worming medication, and gastritis is treated symptomatically.


Capillaria feliscati is a urinary tract parasite that usually invades the lining of the bladder, but it may also be in the kidney or ureters. Cats may show no signs, or they may appear to have lower urinary tract disease. Eggs may pass in the urine. Though rare in the USA, in other parts of the world, such as Australia, it is quite prevalent.

You May Also Like These Articles:

Lice in Cats

Worms in Cats: Feline Intestinal Parasites

Cuterebra Infestations in Cats

Cat Fleas: Does My Cat Have Fleas?

How to Give a Cat a Bath

Cat Parasites

Steatitis: Yellow Fat Disease in Cats

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