Many myths litter the internet and in-person discussions about heartworm disease, and its effect on pets, wildlife, and people. Separating the truth from misinformation can be tricky and, in some cases, harmful to your furry pal if you follow wrong opinions. To set the story straight, Little Animal Hospital is shedding light on common misconceptions about heartworm disease. Answer the following true-false statements, and then learn how to correctly protect your four-legged friend from heartworm disease.

True or false: Heartworm disease affects only dogs

False: While many people believe heartworm disease is a canine condition, that is not correct. Heartworms do prefer to complete their life cycle in dogs and wild canines, but heartworm disease can affect any mammal, cats and people included. Fortunately, serious infection is rare in people, but heartworm disease can be as deadly for cats as for dogs.

True or false: Only pets who are outside a lot are at risk for heartworm disease

False: Pets who spend a great deal of time outside are certainly more at risk for contracting heartworms, but indoor-only pets, like cats, are also susceptible to disease. Heartworms are transmitted via a bite from an infected mosquito, so any pet can be exposed. Mosquitoes can slip into your home through an open door or torn window screen. Plus, here in Longview, mosquitoes do not die off during our mild winters, putting pets at risk all year, which makes year-round heartworm prevention especially important.

True or false: Dogs and cats can have different heartworm disease signs

True: In general, heartworms damage the heart, lungs, and surrounding blood vessels, but the microfilariae (i.e., immature larvae) that migrate throughout the body also cause serious harm. Since heartworms prefer to infect dogs, the disease has a different appearance compared with other species. Dogs typically won’t develop issues until later in the disease process, but in cats, the first heartworm disease sign can be sudden collapse or death.

In dogs, heartworm disease signs can include:

  • A dry, persistent cough
  • Exercise intolerance
  • Fatigue after moderate exercise
  • Inappetence
  • Lethargy
  • Weight loss
  • Abdominal distention from fluid accumulation

Cats tend to develop asthma-like signs, in addition to other vague illness indicators. If your cat contracts a heartworm infection, you may notice:

  • Coughing
  • Difficulty breathing
  • Lethargy
  • Decreased appetite
  • Weight loss
  • Difficulty standing or walking
  • Vomiting
  • Diarrhea
  • Blindness
  • Seizures

True or false: I would know if my pet had heartworms

False: Unlike intestinal parasites, which you can sometimes see in a pet’s stool, you cannot see these worms. Typically, dogs take months to develop obvious signs, and cats may show no signs at all. 

True or false: Diagnosing heartworm disease can be tricky, so annual tests are recommended

True: After your pet has been bitten by an infected mosquito, the disease will progress for about five to six months before a positive result can be obtained on a standard heartworm test. In general, a heartworm test detects the presence of adult female heartworms. If the heartworms are still immature larvae, or too few are adult females, the test can be falsely negative. Since an accurate result is a challenge, testing your pet annually is best.

True or false: Treating heartworm disease is difficult in dogs

True: Once your dog has been accurately diagnosed with heartworm disease, they can begin treatment, which consists of a series of painful arsenic-based injections administered into the dog’s lumbar muscles. During the months-long treatment process, your dog must be kept confined and allowed only short leash walks, because too much activity can cause potentially fatal side effects from a blockage of dying heartworms.

No heartworm disease treatment is approved for cats. At best, symptoms can be managed, but sudden death can occur at any time. 

Now you can see why heartworm disease prevention is incredibly important for your pet. Does your feline friend always spit out their oral medication? Or, does your dog run at the sight of a medication applicator? Don’t worry—our Little Animal Hospital team can help you find the best heartworm prevention for your pet that is easy to administer. Contact our team for recommendations.