Shawn M. Finch, DVM

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July!

Heartworm Disease in Cats

The Good…

Cats are not a natural host for heartworms. They are infected roughly a tenth as often as dogs.

Cats on heartworm preventative medication are completely protected from heartworm disease.

The Bad…

Heartworm disease is difficult to diagnose in cats.

• Before an infection is fulminant, sometimes there are no signs.
• When signs appear, they are often non-specific.
• The ELISA test detects antigens from mature female worms.  Cats usually have a low adult worm burden (typically one to three worms), so the odds of all male heartworms is pretty high.  If that occurs, the test will read as negative.
• An antibody test is available, but can also yield false negatives.  (Back to the good for a second:  The two tests together may increase accuracy.)
• A cardiac ultrasound can detect adult worms in or near the heart, but is much more expensive than a blood test.

I am convinced that because of all of these hurdles to diagnosis, feline heartworm disease is underdiagnosed.

At this point in time, heartworm disease in cats is untreatable. We manage secondary signs and inflammation while we wait for the adult heartworms to die, which can take several years.

The Ugly…

Cats become sick with a very low worm burden.

A common sign is difficulty breathing, which can be mistaken for asthma.

The most common sign of heartworm disease in cats is sudden death.

The End of Feline Heartworm Disease…

Every cat should be on a monthly heartworm preventative medication, even an indoor cat in Nebraska.  That the risk is relatively low would not make one bit of difference to me if Max the Cat were the one to contract heartworm disease and I could have prevented it.

Great information at American Heartworm Society’s website:

Feline Heartworm Disease

Today’s Checklist for the Finch Household:

Noodle the Poodle - Wormshield tablet

Max the Cat - topical Revolution

Give treats to the fish and Joy the Puppy, who is on ProHeart6

Hope you have a happy, healthy, minimal-mosquito heartworm-free summer!

Tags: cats, heartworm, Omaha, veterinarian, veterinary

This entry was posted on Friday, July 1st, 2011 at 6:31 pm and is filed under Actual Medical Information (Mostly), Pet Blogger Hop, Thoughts. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.