Feline Heartworm Disease at Willowbrook Veterinary Hospital
Feline Heartworm Disease: What You Need to Know
Heartworm disease is a serious and potentially fatal condition in cats. While it is more common in dogs, cats can also be infected, and because there is no approved treatment, prevention is crucial. Here’s what you need to know to keep your cat safe from heartworms.
What Is Heartworm in Cats?
Heartworm disease is caused by the parasitic worm Dirofilaria immitis, which is transmitted through mosquito bites. The worms can grow and live in the lungs and heart, causing severe health issues. Unlike in dogs, heartworms do not usually grow to adulthood in cats, but even immature worms can cause serious lung and heart damage.
How Do Cats Get Heartworm?
Cats become infected when bitten by an infected mosquito. Mosquitoes pick up heartworm larvae from infected dogs, foxes, coyotes, or other animals and can then pass them to cats. Even indoor cats are at risk because mosquitoes can enter homes.
What Are the Symptoms of Heartworm in Cats?
Symptoms can be mild to severe and may include:
- Coughing or wheezing
- Difficulty breathing (asthma-like symptoms)
- Vomiting (even without food present)
- Lethargy or sudden collapse
- Weight loss and decreased appetite
- Sudden death in severe cases
- Some cats show no symptoms at all until the disease has progressed.
How Is Cat Heartworm Diagnosed?
Heartworm disease in cats can be difficult to diagnose. Your veterinarian may use:
- Blood tests to detect heartworm proteins or antibodies
- Chest X-rays to check for lung and heart damage
- Echocardiography (ultrasound) to detect worms in the heart or vessels
Since cats typically have a low number of worms, multiple tests may be needed for a conclusive
diagnosis.
Can Heartworm Be Treated in Cats?
Unfortunately, there is no approved treatment to kill heartworms in cats. Unlike in dogs, the medications used to treat heartworms can be fatal to cats. Instead, treatment focuses on managing symptoms and reducing inflammation until the worms die naturally, which can take 2-3 years.
In severe cases, supportive care such as oxygen therapy, steroids, or surgery may be
necessary.
What Are the Long-Term Effects of Heartworm in Cats?
Even after heartworms die, they can cause permanent lung and heart damage. Cats who recover from heartworm infection may still suffer from chronic respiratory disease and an increased risk of heart failure.
How Can I Prevent Heartworm in My Cat?
The best way to protect your cat is with monthly heartworm prevention medication. These medications kill heartworm larvae before they can develop into harmful worms. Preventatives come in oral and topical forms and are easy to administer.
Is Heartworm Prevention Safe for Cats?
Yes! Heartworm preventatives are very safe when given as directed by a veterinarian. They are
much safer than the risks of heartworm infection.
How Often Should My Cat Be Tested for Heartworm?
The American Heartworm Society recommends annual heartworm testing for cats, even if they are on preventatives. Testing helps ensure early detection and allows for timely management.
Can Indoor Cats Get Heartworm?
Yes! Indoor cats are still at risk because mosquitoes can easily enter homes through doors, windows, and vents. Studies show that one-third of cats diagnosed with heartworm are indoor-only cats.
What Should I Do If I Suspect My Cat Has Heartworm?
If your cat shows respiratory issues, coughing, vomiting, or sudden lethargy, contact Willowbrook Veterinary Hospital immediately. Early detection can help manage symptoms and improve your cat’s chances of recovery.
Are Certain Breeds of Cats More Susceptible to Heartworm?
Heartworm disease can affect all cats, regardless of breed. However, some studies suggest that purebred cats like Siamese and Abyssinians may have a slightly higher risk, possibly due to genetic factors.
Can Heartworm Be Transmitted from Cats to Humans?
No, humans cannot get heartworm from infected cats. Heartworms require a mosquito to spread from one animal to another.
How Effective Are Heartworm Preventatives for Cats?
Heartworm preventatives are highly effective when given correctly every month. Missing doses or delaying administration increases the risk of infection.
What Are the Side Effects of Heartworm Medications for Cats?
Most cats tolerate heartworm preventatives well, but possible side effects include:
- Mild stomach upset (vomiting or diarrhea)
- Temporary skin irritation (for topical medications)
- Rare allergic reactions (itching, swelling, lethargy)
If your cat experiences any unusual symptoms, contact your veterinarian.
What Health Complications Can Heartworm in Cats Cause?
Even a small number of worms can cause serious issues, including:
- Heart and lung disease
- Chronic respiratory problems
- Sudden death from blocked blood flow
Prevention is the best way to avoid these risks.
What Should I Do If My Cat Misses a Dose of Heartworm Prevention?
If you’re only a few days late: Give the missed dose immediately and continue with the regular schedule.
If more than a month has passed: Contact your vet, as a heartworm test may be needed before restarting prevention.
Are There Natural Ways to Prevent Heartworm in Cats?
There is no proven natural prevention for heartworm disease. Some holistic methods may help reduce mosquito exposure, but they do not replace veterinarian-approved preventatives.
How Is Heartworm Disease Monitored and Managed in Cats?
For cats diagnosed with heartworm, ongoing care includes:
- Regular vet visits to monitor heart and lung health
- Medications (such as steroids) to reduce inflammation
- Supportive care if symptoms worsen
Since heartworms eventually die off, management focuses on keeping the cat comfortable and reducing complications.
Protect Your Cat from Heartworm Disease
Heartworm disease is a serious threat to cats, but monthly prevention is easy, safe, and effective. At Willowbrook Veterinary Hospital, we can help you choose the best preventative for your cat and provide regular testing to keep them healthy.
Call us today to schedule an appointment and protect your cat from heartworm disease!
Call or Text us at (503) 968-2911, send us an email at [email protected] or