Heartworms in Cats

When you hear people talking about heartworms, you think about dogs.  But did you know that cats can get them, too? 

Cornell University's College of Veterinary Medicine has been studying this very important feline health topic.  Feline heartworm disease is a fatal condition in cats caused when a parasitic worm called Dirofilaria immitis gets into a cat's system.  The only way this happens is through a bite from a mosquito that has already bitten an infected dog.

 

As the climate gets warmer and winters milder, mosquitos have a better chance of living through winters.  This means they'll be buzzing around you and your cat all year instead of just late spring and summer.  That means, as cat parents, you need to be aware of the potential for heartworms in your cat and find out what you can do to prevent it.

When a heartworm parasite enters a cat's skin, it makes its way through the muscle tissue and then into the right ventricle of the heart, lungs and arteries that feed them both.  This process can take eight months.  However, Dr. Dwight Bowman, a professor of parasitology at Cornell's vet school, says that you can detect the symptoms soon after infection.  His work has shown that, between 60 and 100 days after infection, a cat may start to have a severe inflammatory response that will damage the various working parts of the lungs.  He notes that even though this is called heartworms, the parasites usually are most active in the pulmonary arteries that take blood from the heart to the lungs.  Because in cats the lungs are more affected than anything else, veterinary scientists have created a new term to describe this feline condition - HARD - heartworm associated respiratory disease.

Signs of heartworm to watch for are:
* Vomiting (which may include some blood)
* Diarrhea
* Rapid breathing
* Coughing or gagging
* Loss of appetite and weight loss
* Lethargy

If you see any of these get your cat to the vet quickly.  Using blood tests, chest X-rays and an antibody test, your vet will determine if heartworm parasites are there.  Heartworms in cats is incurable since the medicines used to treat it in dogs are fatal to cats.  Vets may choose to use supportive therapy to treat the symptoms, like IV fluids, oxygen as well antibiotics and heart medications.

The best option is prevention, especially in areas that stay warm and humid year round.  In consultation with a vet, your cat may be prescribed products that include selamectin, milbemycin and ivermectin.  Revolution and Bravecto Plus for cats are two flea medications that prevent heart worm.  Be aware, though, do NOT use a flea treatment that prevents or kills heartworms with a heartworm-positive cat.  It will kill the heartworm and, when that happens, the cat will suffer sudden death.   As always, consult with your vet before choosing any product.

CLICK HERE to see the full article from the Cornell College of Veterinary Medicine.

CLICK HERE to get more facts from the American Heartworm Society.