Article about Cats and Worms

There are two species of roundworms affecting cats and kittens: Toxocara cati and Toxascaris leonina. Because both are treated with the same medication, it isn't necessary to determine which species is present once eggs have been seen on a fecal flotation exam. Roundworms are big worms, typically white in color, about the diameter of a spaghetti-strand and about 4 inches long. These roundworms can be seen in your pet's feces or sometimes your kitten or puppy may vomit one up.

Kittens or puppies may be born with roundworms. We know that Roundworm larva are tiny enough to migrate through the placental blood supply to the fetal liver or lungs. Soon after birth, the juvenile roundworms begin migrating from the liver and lungs to the intestine where they grow into adults and begin laying eggs. Within three weeks after birth, puppies and kittens can begin shedding roundworm eggs into the environment. A second source of infection is through the mother's milk. Roundworm larva can gain entry into the mammary glands and then be passed to the puppies or kittens as they nurse. A third possibility is if a young animal eats an embryonated egg found in fecal contamination of food or water bowls or other environmental sources. The egg hatches within the intestine and a "Blood-Lung" migration begins.

Tapeworms are another type of worm. Tapeworms are among the best adapted of parasites, meaning that they harm their host the least. Some animals may develop diarrhea, weight loss, or vomiting. However, most cats do not have any clinical signs associated with tapeworm infestation. The most common tapeworms are Diplidium caninum, which is a segmented tapeworm that lives in the cats small intestine. Each segment of the worm contains maturing eggs. These segments, when passed from the cat, resemble grains of rice that you may notice around the cat's anus, on the cat's coat, or on her bedding. These segments can cause anal irritation and excessive licking of this area.

Tapeworms are spread by the ingestion of fleas. The flea larvae swallows the eggs from the tapeworm segment. These eggs mature as the flea matures, making the adult flea infectious to the cat. When the cat ingests the flea, the tapeworm larvae are released into the small intestine and so the cycle goes on again. Treatment should include a flea treatment to help prevent reinfestation. The symptoms of this type of tapeworm infection can be, in severe cases, abdominal pain and an increase in food intake. Tapeworms can infect humans so cats should be wormed regularly and a flea control program carried out.

Taenia taeniaeformis is also a segmented tapeworm, though it is larger and less common than Dipylidium caninum. They have nothing to do with fleas but are transmitted from infected rats, mice and voles to the cat. The adult tapeworm lives in the cat's intestine, and the segments containing the maturing eggs are passed in the feces. The same worming treatment can be used as for dipylidium caninum. These types of tapeworms do not transmit to humans.

Aelurostrongylus abstrusus is a small worm that lives in the air passages of the lungs. There are usually no outward signs that your cat has this worm unless she is heavily infested, in which case the cat would be coughing. Again, this worm does not transmit to humans.

Toxoplasmosis is a disease of cats as well as other mammals and birds and is caused by a parasite called Toxoplasma gondii. Toxoplasma infection is common, but a full-blown case is rare. T. gondii is important because virtually all warm-blooded animals, including man, can become infected with it. Domestic, wild, and feral cats can transmit Toxoplasma infection to humans. Cats have a 20% to 60% infection rate with T. gondii. Its prevalence is related to several factors including the ingestion of infected animals like rodents and birds as well as raw meat. Stray and feral cats have a higher incidence of infection than pet cats, and older cats have more of a chance of acquiring it.
Symptoms of toxoplasmosis include anorexia, weight loss, lethargy, difficulty breathing (because of pneumonia), eye inflammation, and fever. Other symptoms are vomiting and diarrhea, neurological symptoms, swollen lymph nodes, and jaundice. This infection can be very dangerous in pregnant women and requires immediate medical attention.

Back to Cat Health Articles