At Advanced Animal Care, our highly experienced team of veterinarians and veterinary support staff have been helping educate our clients and win the fight against heartworms in cats since 2009. The importance of heartworm prevention for cats cannot be overstated, as heartworm disease in cats can lead to severe respiratory disease and even death. Therefore, preventive measures are absolutely necessary in order to keep your beloved feline friend healthy and safe.

What Is Dirofilariasis, AKA: Cat Heartworm?

Heartworm disease in cats is transmitted by mosquitos carrying heartworm larvae. An infected mosquito bites a cat, and injects the larval (or baby) heartworms into the cat's body. The larval heartworms then travel to the cat's heart and lungs, where they live and cause significant lung and heart damage and inflammation. A heartworm can live in a cat's body up to 7 years! The severity of heartworms in cats is directly dependent upon the number of heartworms present a cat's body, the duration of the infection, and the response of the infected cat.

Although heartworms in felines are less prevalent than in canines, feline heartworms are still a dangerous disease that has been on the rise in America. If you do not use preventive medication, the risk of your cat potentially contract heartworm disease increases significantly. This is why preventive cat heartworm medication is so important.

Symptoms Of Cat Heartworm Disease

One of the most challenging aspects of diagnosing heartworms in cats is that there are no definitive clinical signs that directly indicate the existence of cat heartworm disease. However, this doesn't necessarily mean that cat heartworm disease isn't present. Some health signs that might indicate the presence of cat heartworm disease include:

Vomiting and coughing are two of the most common symptoms but there may be other symptoms, including:

  • Difficult or labored breathing
  • Lethargy
  • Anorexia or decreased appetite
  • Weight loss
  • Coughing
  • Vomiting
  • Sudden Death

On occasion, an apparently healthy cat may be found dead, or may develop severe, acute difficulty breathing and die rapidly. In these cases, cat heartworm disease may be diagnosed on a post-mortem examination.

We can easily prevent cat heartworm long before serious medical issues or life threatening emergencies develop by simply implementing preventive measures.

How Are Cat Heartworms Transmitted?

Upwards of 30 species of mosquitoes can act as cat heartworm vectors. Mosquitoes ingest immature heartworm larvae, called microfilariae, by feeding an infected animal. The microfilariae develop into the infective stage inside the mosquito, then, when an infected mosquito bites a cat, it injects the heartworm larvae into the cat. The larvae then migrate and mature over a period of several months, eventually ending up in the right side of the cat's heart, heartworms can also live in the lungs and associated blood vessels.

Diagnosing Heartworm For Cats

Unfortunately, there is no one benchmark standard used across the veterinary industry for diagnosing heartworm for cats. Rather, our veterinarians employ a battery of lab tests in order to determine a cat heartworm diagnosis. These tests include:

  • A heartworm antibody test determines whether or not a cat's immune system has been exposed to heartworms. This is a very sensitive test, and is usually employed first.
  • A heartworm antigen test determines the presence of adult female heartworms. This is more specific than an antibody test, but not as accurate in all cases, as some cats may be only infected by male heartworms.
  • Radiographs, or X-Rays, that allow us to view the size and shape of a cat's heart. Radiographs are helpful in assessing the condition of the cat's heart and lungs, but they do not definitively diagnose heartworm disease in affected cats. 
  • Ultrasounds allow us to view the internal structures of the heart and surrounding vessels, in order to assess the condition and function of the heart. 
  • A white blood cell count can be measured in cats suspected of having contracted heartworms. Eosinophils are a type of white blood cell which occur in higher numbers whena cat is infected with heartworms, but can also indicate the presence of other parasites besides cat heartworm.

Heartworm Medicine For Cats

Unfortunately, there is currently no medication that kills mature adult heartworms and is safe for cats. Therefore, if your cat is diagnosed with heartworm disease, we typically manage the disease while we wait for the adult heartworms to die. While sudden death is possible if a cat is infected with heartworms, it isn't common. If your cat is diagnosed with heartworm they may still live a long life under the supervised medical care and treatment of your veterinarian. This may include anti-inflammatory medications and bronchodilators, similar to those used to treat asthma.

Heartworm Prevention For Cats

The good news for cat owners and their feline friends is that reliable heartworm prevention for cats does already exist. Veterinarians strongly recommend that all cats receive monthly heartworm preventive medications in areas where mosquitoes are active all year round. Here in KY and because of our mosquito population, we highly recommend all cat owners adhere to this annual preventive medicine protocol.

Have A Veterinarian Check Your Cat For Heartworm At Your Next Appointment

We recommend scheduling an appointment to discuss heartworm prevention for cats with us before your cat contracts heartworm. If you witness any symptoms that might be indicative of cat heartworm disease, please contact us immediately to schedule an appointment. Our veterinary team will provide you and your feline friend with an effective cat heartworm prevention protocol.