Colorful female marble Bengal kitten from Foothill Felines.

 HEARTWORM DISEASE IN FELINES 

While heartworms have been reported as early as 1626 in dogs in Italy, it wasn't until the 1920's that this hardy parasite (Dirofilaria immitis, which can also infect humans, all members of the cat family, and 30 other species of animals) was diagnosed as having infected felines. While in dogs this thin, string-like worm is often thought of as a minor annoyance to be dealt with through medication ... in cats, the heartworm can kill.

It is very rare for a human to get heartworms.   Even if a heartworm does enter a human body, before it can have any impact on its host, it usually dies. Mosquitoes are the most common "intermediate hosts" of heartworm, and thus it is that the areas where the climate is warm and humid, such as the southeastern USA, Latin America, Asia and Europe, are the areas where heartworms also thrive. The disease is carried by a mosquito that has drawn the blood of a dog infected with heartworm, and can cause the heartworm disease to spread to a cat by then regurgitating the heartworm larvae on a cat. It is very uncommon for affected cats to infect other cats - to be passed on, the disease appears to require transmission via an infected dog to a mosquito to a cat. Since mosquitoes can be quite persistent and remain indoors, even if you keep your cats indoors 100 percent of the time, they can still become infected with heartworm disease.

While in dogs, the heartworm larvae can migrate to the heart (where they can grow to be up to six inches long and live for about 5 years without causing serious problems) ... in cats, the heartworms react very differently and a single heartworm, at a length of three to four inches, can kill a cat. Cats are not the normal host for the heartworm larvae, which tend to migrate in cats from the mosquito bite location to the lungs, and then take up residence in the pulmonary arteries, where they can cause serious respiratory problems in the cat, vomiting, or even sudden death.

The symptoms of heartworm disease in a cat can include coughing, gagging, lack of appetite, weight loss and lethargy, difficulty breathing, repeated vomiting, heart murmur, blindness, and central nervous system disorders. The critical indications of severe and life-threatening heartworm disease are pulmonary infarction, circulatory collapse, respiratory failure, and sudden death.

Heartworm disease in felines has been documented in at least 38 states here in the USA. Accurate diagnosis of heartworms requires two (or more) tests, which include an antigen (sometimes called a "serum" or "plasma" test) that detects the substance produced by adult female worms. This test, however, does not rule out the presence of male or immature worms. A second type of test is an antibody test done to detect presence of worms. Another type of test is called a "microfilariae" test, which is a blood test done to detect immature worms that have been present for at least 1-2 months. Some vets also perform an echocardiography test (ultrasound test) or an x-ray test, and there is also a test involving injecting a dye into the veins of the cat and watching by x-ray. Many vets prefer to give the antibody and antigen tests, as a positive test result show that the cat has been exposed and therefore should have the preventive treatment, even if the cat is not actually infected with the heartworms.

Amazingly, in rare cases some cats appear to be able to mount their own antibody response to their heartworm problems, and actually rid themselves of the condition without medical intervention. It is important to know that the diagnostic tests that have always worked well in dogs are not nearly as accurate in cats, based upon the different responses of the worms in cats noted above. There is a relatively new antibody test on the market now, called Heska Feline Heartworm Reference Lab Diagnostic Test, which can detect even a single male heartworm, as it is sensitive enough to detect a single-sex worm infection, or infections with very small numbers of adult and immature heartworms. This is important because heartworms are notorious for their ability to hide and thus be difficult to detect in cats.

Prevention is the best way to keep heartworms away from cats. For about $3.50 per month, there is a monthly heartworm preventive available, Heartgard, by Merck, (available only from licensed veterinarians) which kills heartworm larvae. Heartgard can be given alone or mixed with food, and comes in two formulas, based upon the cat's body weight. Many veterinarians now agree that it makes sense to put all cats in a heartworm-endemic area on the preventive medication, which works by killing the heartworm larvae. It does not kill adult heartworms already in cats, but will keep cats from becoming reinfected. Killing the adult heartworms already in cats does not appear to be the best solution, as when a worm dies and begins to deteriorate, small pieces of it can clog the arteries and cause the death of the cat. Also, when a worm is inside a cat, it secretes a substance that prevents the cat's own immune system from reacting negatively to it. If the worms die and remain in the cat's system, that substance will no longer be secreted, and the cat could react negatively to the worm (actually, the cat's immune system would then be attacking the cat's own body tissues) and chances are very high that the cat would die. Even more recently, there is a newer version of "Advantage®" for cats, which, in addition to flea and tick prevention, also contains an effective medication for heartworms.

Surgery is a last resort for heartworm disease in cats and is full of dangers in a feline heartworm patient. If there is no other option in a cat with multiple worms and no way to survive on its own, surgery may need to be performed. Using tiny forceps to twist the heartworm (twirling it like pasta on a fork), the surgeons must make sure to get ALL of the worm or worms. If even a tiny piece of the worm is left in the patient, it can cause a pulmonary embolism and sudden death. There is a much greater sense of hope, relief and optimism among the veterinary community and cat owners today regarding controlling feline heartworm disease, with the effective heartworm preventive now readily available on the market.

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NUVET PLUS FELINE SUPPLEMENT

~ Give your kitty the energy, great health and desire to enjoy life to the fullest! Used and recommended by Foothill Felines, click on image above to order this uniquely powerful nutritional supplement for felines at our Foothill Felines breeder discount. Just a pinch a day, sprinkled onto wet and/or dry food, energizes and supports all ages, weights and breeds of cats. Developed by scientists, veterinarians and formulators to enhance the health and lives of cats, this unique Nu- Vet supplement contains many important minerals, antioxidants, enzymes and vitamins especially needed by active felines' metabolisms INCLUDING taurine, calcium, blue green algae, brewer's yeast, and much more.

   
FELIWAY PLUG-INS & SPRAY
~ Click on links above for more information and to order these exceptionally calming Feliway products for felines. Used and recommended by Foothill Felines! Wonderful for cats of all ages, weights, and breeds. Contains natural cat pheromones for extremely effective stress relief and eliminating need for cats and kittens to mark or exhibit other unwanted behaviors. Every multi-cat household should know about these plug-ins; they are odorless to people, yet they are especially helpful to kittens/cats during a move, any change in your household routine, periods of stress of any kind, and queening.

TOY-GO-ROUND CAT EXERCISE WHEELS ~ Click on image above to learn about the incredible new exercise wheels for cats; the Toy-Go-Round wheels!! They're simply the best designed, best built and best priced wheels we've found anywhere!!

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