Heartworm disease is a constant threat to pets in all 50 states, including Kansas. Whether your pet is currently on regular heartworm prevention, or has never received a dose, read the answers to these frequently asked questions, to assess your pet’s risk, and make the best decision for her life-long health.

Question: What is heartworm disease?

Answer: Heartworm disease is caused by an infection with a parasitic worm, Dirofilaria immitis, that lives in the heart and lungs of infected pets. The worms, which can grow to 12 inches long, interfere with normal blood flow through a pet’s heart and lungs, and can cause significant inflammation that leads to life-long damage, including in pets who are treated and recover from infection. If left untreated, heartworm disease progresses to cause death.

Q: How are heartworms transmitted to pets?

A: Heartworms are transmitted when a mosquito takes a blood meal from an infected dog, and picks up microscopic larval heartworms that can be transmitted to other animals it bites. Most animals, including humans, are dead-end hosts for the worms, which simply die after transmission. Dogs, however, are the heartworm’s preferred host, and the worms can mature, and multiply into a large population in your dog’s heart and lungs.

Q: Can cats develop heartworm disease?

A: Like most animals, cats are a dead-end host for heartworms, but they can still cause considerable inflammation and disease. Although the worms cannot reproduce and accumulate to large numbers in cats, the few worms that a mosquito transmits can reach maturity, and live for up to three years. 

Q: What are heartworm disease signs in pets?

A Unfortunately, heartworm disease often causes few or no clinical signs until a large worm population has developed, which strains your pet’s heart, obstructs blood flow, and causes considerable inflammation and scarring to your pet’s lungs. Affected dogs may show vague signs that include:

  • Lethargy
  • Tiring easily
  • Decreased appetite
  • Coughing
  • Vomiting

Heartworm disease is often silent in cats, who can collapse and die suddenly, without prior warning, from significant lung damage. Cats who show clinical signs may have the same symptoms as dogs with the disease.

Q: How do I know if my pet has heartworm disease?

A:  Your pet should be tested for heartworm disease during her yearly wellness visit—a few drops of blood will tell us if she is harboring adult heartworms in her body. After a negative test, your pet can be started on a heartworm preventive. If this is your pet’s first test, and she has not been on prevention previously, we will test her again in six months to ensure the test did not miss any juvenile worms. Your pet may regularly receive heartworm prevention, but she still should be tested annually, because if she misses only one dose, spits out a pill, or vomits one in a backyard corner, she can be left unprotected. 

Q: Can heartworm disease be treated?

A: In dogs, heartworm disease can be treated with an injection series to kill adult worms, as well as several oral medications to kill developing immature forms, decrease inflammation, and kill bacteria carried by the worms. Treatment is hard on dogs, because as worms die, they can clog up lung vessels, and cause a life-threatening pulmonary embolism. Throughout the treatment period, dogs must adhere to strict cage rest, with controlled leash walks for potty breaks only. 

Unfortunately, no treatment that effectively kills heartworms in cats is available, so treatment focuses on decreasing inflammation associated with the worms’ presence, until the worms die on their own. 

Q: Does my pet really need heartworm prevention?

A: Regular preventive medication is key to stopping heartworm disease in its tracks. The medication, which is typically administered to your pet monthly, kills immature worms before they can reach maturity and reproduce. If you think your pet is not at risk, the Companion Animal Parasite Council reported almost 900 cases of heartworm disease in Kansas pets during 2019, and expects more cases in 2020. Indoor pets are also at risk—according to the American Heartworm Society, 25% of cats diagnosed with heartworm disease are indoor-only pets.

Q: Can I skip my pet’s heartworm prevention during the winter?

A: Heartworm disease can be transmitted any time mosquitoes are active, which includes any day the temperature reaches 50 degrees or above. With our recent mild Kansas winters, mosquitoes can be active every season, making year-round heartworm prevention a necessity. Also, heartworm preventatives protect your pet from some intestinal parasites, which can be transmitted year-round. 

Q: Which heartworm preventive is right for my pet?

A: We stock a variety of heartworm prevention products in our on-site pharmacy, and a team member can help you decide which option is best for your pet. 

As you can see—canine or feline, indoor or not—every pet is at risk of heartworm disease, and deserves regular prevention. Contact us to schedule an appointment, and get your pet on the right track to prevent this life-threatening disease.