Heartworm Symptoms in Cats


Heartworm in cats is variously treatable. It is important to know the symptoms, causes and areas at risk and to be prudent in treatment. Although heartworm disease in cats was once confined largely to warm and wet areas, it has now spread globally.

What is Heartworm?

The dirofilaria immitis is a roundworm parasite that travels from host to host through the blood, transferred by mosquitoes biting multiple victims. The worm itself is a filament-like, slim worm that completes its life cycle in mammals.

Heartworm in Cats

Cats are far less likely than dogs to develop heartworm. Typically they get fewer worms and the period of infection is shorter than in dogs. But cats are more likely to have heartworms migrate to other areas of the body than are dogs, causing more problematic infections and symptoms. Dying worms in the pulmonary arteries can be fatal to cats. Often, because cats rarely get heartworm, the disease is misdiagnosed as a respiratory problem.

Common Heartworm Symptoms in Cats

Heartworm symptoms, which include coughing, lack of energy, loss of appetite and weight loss, are similar to that of dogs’. But also, cats can experience shock, fainting, diarrhea and sudden death at the severe end of the infection.

Heartworm diagnosis also depends upon a test for the presence of female worm antigens. These antigens will only be indicated after minimally seven months of infection, so a cat could easily die before the test indicates positive for heartworms. An antibody test is also available, but cats will test positive up to several months after expelling all worms. X-ray and echocardiography tests are used by vets to detect adult worms in the heart.

Heartworm prevention in cats is highly problematic. Heartworm treatment, therefore, imperfectly consists of the use of a monthly heartworm drug and a short-term cortiscosteroid, the steroid produced in the adrenal cortex. Treatment for cats is imperfect at best, at present.

To date, except for the removal of standing water and isolation from possibly infected animal populations and mosquitoes, there are no “natural,” herbal, biodynamic, or organic ways of dealing with heartworm infection.

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