Though heartworm infections are more common in dogs, cats can get heartworms. While dogs usually develop a large number of heartworms that can eventually cause heart failure if untreated, cats typically harbor very few adult worms. However, when the cat's immune system starts attacking the heartworms, it can cause a deadly anaphylactic reaction that is difficult to treat. Here, in the state of Indiana, heartworms are a big problem.
Heartworm Life Cycle
Mosquitoes become carriers of heartworm larvae when they feed on an infected animal. When the infected mosquito bites a cat, the larvae enter the cat's system. Cats are not a natural host of heartworm larvae and the life cycle is less likely to be completed. Worms that do survive in the cat's system can cause an immune reaction that could create severe health problems.
There is a great computer animated video that has been put together by the American Heartworm Society that shows the life cycle of the heartworm, and how it effects cats.
The video can be viewed here: http://www.heartwormsociety.org/pet-owner-resources/feline.html
Signs & Symptoms
Below is a list of some signs & symptoms that could be associated with feline heartworm infection:
- Persistant cough
- Breathing difficulty
- Depression
- Loss of Appetite
- Weight Loss
- Vomiting
- Lethargy
- Blindness
- Syncope/fainting
- Tachycardia/fast heart rate
Health problems that can affect your cat, should they become infected with heartworms:
- Damage to heart & lungs
- Damage to pulmonary (lung) vessels
- Obstruction of blood flow
- Difficulty breathing
- Heart & lung failure
- Kidney & liver damage
- Sudden death
Diagnoses
It can be difficult to diagnose feline heartworm infections. Radiographs (Xrays) and bloodwork will be done when a cat is symptomatic. Since cats are naturally stoic creatures, it may be hard to tell that your cat is sick until the disease has become a major problem. If you notice your cat displaying any signs of respiratory distress, such as coughing, panting, open-mouth breathing or wheezing, it's a good idea to take your cat to the veterinarian immediately.
Prevention/Treatment
This deadly disease is much easier to prevent than it is to treat. There are currently no products approved for cats, in the US, for the treatment of adult heartworm infections, so prevention is key. Even indoor cats can be bitten by an infected mosquito, as they can easily enter a home from an open door or window, and it only takes one bite from an infected mosquito to cause infection. We recommend that your cat be seen by a veterinarian yearly, and be kept on a regular monthly preventative, such as Advantage Multi or Revolution.
Written by: Erricka Jones & Dr. Aimee Hossler
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