Feline Heartworm Disease

Many people do not realize that cats can get heartworm disease. Heartworm disease is not just a canine disease. Cats are getting heartworm far more often than was previously believed. During a recent study, it was found that 26% of the cats tested had been infected with heartworm larvae at some point in their lives.

Indoor cats are not impervious to heartworm infection. A North Carolina study found that 27% of cats diagnosed with heartworm were indoor-only cats. It only takes one mosquito to cause an infection, and because mosquitoes can get indoors, both indoor and outdoor cats are at risk.

The name “heartworm disease” is a misnomer for cats, as it mostly affects their lungs, not their heart. Because cats are unique in their respiratory reaction to heartworms, a new title has been given to this particular set of symptoms: heartworm-associated respiratory disease, or HARD. Cats that suffer from HARD can have difficulty breathing and can die from the disease. However, even in the late stages animals often exhibit no symptoms.

Unlike dogs, cats do not need an adult heartworm to exhibit clinical signs; in fact, larvae are a main cause of the problems. Studies show that 50% of cats infected with heartworm larvae have significant damage of the small arteries that supply blood to the lungs.

Diagnosis is much more difficult for cats than it is for dogs. If your cat is exhibiting signs of heartworm disease (ie., coughing, difficulty breathing, vomiting), talk to your veterinarian.