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Educational Articles

Cats + Parasites

  • Fleas are the most common nuisance and parasite affecting cats, and an infestation can lead to serious health problems. Flea control requires a three-pronged approach; they need to be eliminated from 1) your cat, 2) any other cats and dogs that you have, 3) your home and yard. There are many flea control products available and your veterinarian can help you determine which are safest and most effective for your pets.

  • Fluralaner is given by mouth or applied topically and is used to treat flea and tick infestations, and also off-label to treat certain types of mange and mites. Give as directed. Side effects are uncommon but may include stomach upset or neurologic symptoms. Do not use in pets with a history of seizures. If a negative reaction occurs, please call the veterinary office.

  • Giardiasis is an intestinal infection caused by a microscopic protozoan. The parasites attach themselves to the intestinal wall and the damage causes an acute, sudden onset of foul-smelling diarrhea. Diagnosis may be by routine fecal flotation or presumptively based on clinical signs. Fenbendazole and metronidazole are the drugs most commonly used to kill Giardia. Giardiasis is the most common intestinal parasitic infection of man and can potentially be passed from cats to humans.

  • Harvest mites, also known as red bugs, trombiculid mites, scrub-itch mites, berry bugs or, in their larval stage as chiggers, are mites that are commonly found in forests and grasslands. Harvest mites are relatives of spiders.

  • Heartworms (Dirofilaria immitis) are blood-borne parasites that reside in the heart or nearby large blood vessels of infected animals. Recent studies of cats with heart and respiratory diseases have found an incidence of heartworms that is far greater than previously thought. Veterinarians now strongly recommend that all cats receive year-round monthly heartworm preventives. There are excellent heartworm preventives now available for cats, making prevention of heartworm disease safe and easy.

  • Heartworms are blood-borne parasites that reside in the heart or adjacent large blood vessels of infected animals. There is no drug approved for treating heartworms in cats and surgical removal is generally the best option. Veterinarians now strongly recommend that all cats receive year-round monthly heartworm preventative in areas where mosquitoes are active all year round. Cats that live in colder areas, where mosquitoes are seasonal, should be given monthly preventives for at least six months of the year.

  • Hookworm is a parasitic infection of the gastrointestinal tract of cats. Their name is derived from the hook-like mouthparts they use to anchor themselves to the lining of the intestinal wall. How the infection is spread along with clinical signs, diagnosis, treatment, and prevention are covered in this handout.

  • Imidocarb dipropionate is an injectable medication that is administered by a veterinarian to treat babesiosis in dogs. It is also used off-label to treat other protozoal infections in dogs, cats, and horses. Most common side effects include mild drooling, tearing, vomiting, or nasal drip. Do not use in pets with exposure to cholinesterase-inhibiting drugs, pesticides, or chemicals. If a negative reaction occurs, please call your veterinary office.

  • This handout outlines common internal parasites in cats. Included are parasites of the gastrointestinal tract (roundworms, hookworms, and tapeworms), as well as parasites of the circulatory system (heartworms). How each of these parasites can affect your cat and what you can do to prevent or treat infection are explained.

  • Lung flukes in North America are parasites called Paragonimus kellicotti that infect the lungs of cats after they have eaten an infected crayfish or rodents that have eaten infected crayfish. Eggs are then released by the parasite into the cat’s sputum to be coughed out or swallowed and released in the feces to continue the life cycle. Lung flukes can be found anywhere in North America but more commonly around the Mississippi River and Great Lakes. Infected cats can be symptom-free or may develop cough with sometimes bloody mucus, pneumonia, pneumothorax, lethargy and weakness. Diagnosis can include locating eggs of the parasite from feces or mucus from the lungs. X-rays can also reveal cysts in the lungs caused by the parasite. Treatment requires one of 2 commonly used anti-parasitic medications: Praziquantel or Fenbendazole. Although zoonotic, these parasites won’t transmit directly from cats to humans.