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Feline Heartworm Disease

Heartworm disease is transmitted to cats when mosquitoes, infected with the parasite named Dirofilaria immitis, take a blood meal from your pet. Because cats are not the natural host for heartworm infection, the symptoms related to infection are different than in the dog. Heartworm infection in cats can be a silent killer causing a range of vague symptoms that seem to have no correlation to the infection itself. Cats with heartworm disease may develop a cough (similar to a cat with asthma) and have intermittent lethargy and vomiting; they may die suddenly. Diagnosis of heartworm infection in cats can be challenging due to the small number of worms that mature in the cat. Although the worm burden tends to be small, the inflammation created by the infection can be tremendous. Specialized blood tests and heart ultrasounds aid in the diagnosis. There is no safe treatment to eliminate heartworm infection in cats. Infected cats receive symptomatic therapy to control the inflammation incited by the worms. Severely infected cats may require surgical removal of the heartworms. The best treatment for heartworm disease in cats is prevention. All cats, not just outdoor cats, should receive year-round monthly heartworm prophylaxis to prevent life threatening heartworm infection.