Dangerous Myth: Cats Are At Risk for Heartworms - June 11

by Cheryl Waterman

Unfortunately, many of us have been under the false impression that our cats are not susceptible to heartworm disease. That may be because until recently not much has been publicized regarding feline heartworm disease, proven by the fact that studies show that less than 5 percent of U.S. households with cats regularly administer heartworm prevention, while 59 percent of households with dogs use a heartworm prevention product on a regular basis.

The American Heartworm Society, an organization called “KNOW Hard” and others such as the American Association of Feline Practitioners are in the process of spreading the word about this potentially deadly issue.

KNOW states that, “One mosquito bite can infect a cat with heartworm.”

While some of us may feel that our cats are not prime candidates for this disease, due to the fact that we keep them indoors, KNOW states that, “28% of cats diagnosed with heartworms are indoor cats.”  This reminds us that mosquitoes get inside our homes, and so, do present a risk to our indoor cats, as well as outdoor kitties.  
As I researched this article, I thought about the questions you, as readers, may have about this disease, and will attempt to answer these questions.

Q  What exactly are heartworms and how can they affect my cat?
A   Heartworms are exactly what they sound like…parasitic worms that can live inside our pets. Cats typically have fewer than dogs, and the life span of the parasite is shorter in cats, but the consequences can be much more serious. The cat contracts this disease when a mosquito carrying microscopic-size heartworm larvae bites a cat. The larvae enter through this bite wound and develop in the tissues. These immature worms then enter blood vessels and are carried to arteries in the lungs, where an inflammatory reaction is caused. Most worms die at this stage, causing even more inflammation. Worms that do progress to adults can live undetected for a couple of years, but when adults die, the inflammation can be severe enough to cause death.

Q  What are the signs or symptoms of feline heartworm disease?
A  Chronic signs of feline heartworm disease include difficulty breathing, gagging or coughing, heavy breathing and vomiting. These respiratory symptoms associated with these reactions are called Heartworm Associated Respiratory Disease or H.A.R.D. Remember, however, that many cats with heartworm infection may show no signs at all.

Q  Is there a test for feline heartworm disease?
A  There are antigen and antibody tests that can help or rule out feline heartworm disease; however these tests have their limitations. Unfortunately, a “false” test doesn’t necessarily mean that a cat does not have heartworms.

Q  Are there treatments or preventatives for heartworm disease?
A The short answer is “yes.” However, the treatments can range from monitoring by x-ray to actual heartworm extractions. As with most disease, the very best treatment is prevention.  There are actually three different approved preventatives for feline heartworm. They are as follows:
• Revolution® manufactured by Pfizer, which is administered topically once a month.  This preventative also protects against fleas, treats and controls ear mites, intestinal hookworms and roundworms;
• Advantage Multi™ for Cats, manufactured by Bayer, which is administered topically; and
• Heartgard^® for Cats, from Merial, which is administered orally, also protects against hookworms
Ask You Veterinarian

While any of these products may do the trick, the best way to proceed is to ask your veterinarian about the best option for your feline.

Cheryl Waterman is the Hospital Administrator at the Cat Clinic of Johnson County and a long-time cat lover. She has been with the Clinic for the past 13 years, and in 2007 received Certification in Veterinary Practice Management (CVPM) designation. She is a member of the Veterinary Hospital Managers Association and the American Animal Hospital Association. You can contact her directed at the Cat Clinic of Johnson County, (913) 541-0478.  www.catclinicofjc.com