Common Feline Parasites and Worms

​While outdoor cats are more at risk, all cats can get parasites. When I found Silver living on the streets, he had Giardia. When Mr.Frisky had to stay for three days at a Veterinary clinic, he came home with Tapeworms.

The most common parasites for cats - even indoor cats, because you or your dog can bring some of these in on your shoes or clothing - are fleas, ticks, roundworms, hookworms, and tapeworms. If your cat drinks water from outside sources, Giardia is a risk.

Fleas and Ticks
Like dogs, cats should receive flea and tick prevention monthly treatment. As with my dogs, I like FrontLine. However, with cats you have to ensure they do not groom each other for several hours to ensure they don't lick it off. My cats have never been pill friendly, so I prefer a topical method versus continuing to be nearly eviscerated trying to pill Garth!

A severe flea or tick infestation on your cat or kitten can even lead to anemia because they can suck more blood than the cat can produce! There are also cats (and dogs) with flea allergies, causing them to obsessively scratch and chew at their skin, creating bald "hot spots" that are hairless, red, and crusty. Fleas also carry tapeworm eggs.

Other Parasites and Worms
Internal parasites come in several forms: roundworms, hookworms, tapeworms and protozoa. In general, they all setup shop in the GI tract.

Common signs are appetite loss, weight loss, vomiting, diarrhea, mucoid or bloody feces.

For Mr. Frisky the tapeworm sign was when I saw what appeared to be a small grain of white rice stuck to his rear end. For Silver, the Giardia caused him to lose his appetite and have diarrhea.

If you suspect your cat is infected, usually the Vet will request you bring in a fecal sample along with the cat for the visit. They will give you a vial ahead of time. Ask them how far ahead you can get a sample that is still viable. Sometimes you may have to leave the cat there for the day so they can get a fresh sample. A fecal sample is not only vital for diagnosis at the beginning of treatment, but vital to verify treatment is complete.

Giardia causes the cat terrible abdominal cramps, loss of appetite, vomiting, and diarrhea. It is caused by a microscopic protozoa parasite in unsafe water such as water from the street gutters, untreated bird baths, streams, rivers, and ponds. When an infected cat defecates, cysts in the feces can infect another cat - as can another cat grooming the cat in the rectal area.

Metronidazole is commonly used to kill Giardia. In order to get the correct dose for cats, the tablet must be split and it is extremely bitter. Some pharmacies can compound it into flavored formulas. I mixed it the juice drained from albacore tuna cans to get Silver to eat it - I did not mix it into a can of food as he was not eating a lot and some or all of the dose would have been missed. However, he would happily lap up the tuna juice immediately and it helped keep him hydrated too which was important with the diarrhea. I also found Silver could not tolerate the entire daily dose given all at once without a severe reaction. After discussing with the Vet, I had to break dose in half and give the half the dose of powder mixed into the tuna juice twice a day instead of the whole dose of powder once a day. If dehydration or severe diarrhea is present, your Vet may also need to give fluids.

Because of the issue of spread via litter box sharing or grooming, Silver was why I initially setup a "recovery room" (
see our videoon that for more information). Once quarantine is over (which is verified by a fecal sample the Vet will review), anything that cannot be completely sanitized with a bleach solution will need to be throw out. For Silver I used disposable litter pans and threw them out along with the litter. I sanitized his bedding. The toys were thrown out as they could not tolerate bleach. The bowls for food and water were stainless steel so they could be easily sanitized, unlike plastic.

I also used disposable latex gloves from the grocery store to scoop litter, and used a separate scoop and bags which I then threw out afterwards.
Roundworms are the most common internal parasites in cats, resembling spaghetti. Nursing kittens can get roundworms from an infected mother’s milk, while adult cats can acquire them by ingesting an infected rodent or the feces of an infected cat.

Hookworms are much smaller than roundworms and reside primarily in the small intestine. Because they feed on an animal’s blood, hookworms can cause life-threatening anemia, especially in kittens. Hookworm eggs are passed in the stool and hatch into larvae, and a cat can become infected either through ingestion or skin contact.

Tapeworms are segmented and flat. An infestation can cause vomiting or weight loss. Cats acquire tapeworms by ingesting an intermediate host, like an infected flea or rodent. When cats are infected, tapeworm segments-actual pieces of the worm that resemble grains of rice-can often be seen on the fur around a cat’s hind end. This is how I discovered Mr.Frisky had tapeworm.

Sources: Texas A&M School of Veterinary Medicine, PetsWebMD, VCA Hospitals