Heartworm disease is a real threat to your pet’s health, and can prove fatal if left untreated. A number of misconceptions surrounding heartworm disease exist, which can make knowing how to best protect your pet confusing. Learn how to defend your four-legged friend against heartworm disease by reading our Sixes Animal Hospital at BridgeMill team’s list of important facts about this serious condition.

#1: Heartworm disease in pets is not directly contagious

Unlike with many other illnesses and parasites, an infected pet cannot transmit heartworm disease to another pet, nor can an uninfected pet contract the disease from other pets. Only an infected mosquito’s bite can transmit heartworms to your pet. While heartworm larvae mature and reproduce inside mammals, the larvae can only reach the infective stage through stimulation by a mosquito’s gastric juices. So, without mosquitoes, heartworm disease would not exist.

#2: Heartworm disease can affect any pet, any time of year

Heartworms don’t discriminate, and will set up residence in any mammal. However, these parasites prefer canine hosts, and thrive for longer in dogs than they do in cats. 

Because Canton’s winter temperatures rarely settle below freezing for long, the mosquito population persists, making year-round heartworm prevention critical to your pet’s health. However, in areas of the United States that experience much colder temperatures, mosquito activity can endure even in the winter. A mild day during which the temperature rises above 50 degrees is enough for mosquitos to head out in search of a meal. Therefore, no matter where you live, your pet should receive year-round preventive medication.

#3: Pets’ heartworm disease signs can take months or years to manifest

Although some diseases rapidly cause illness, heartworm disease progresses slowly. After an infected mosquito’s bite, the heartworm larvae grow for about six months before reaching adulthood. During that time—as they migrate to an infected pet’s pulmonary artery—the larvae permanently scar the host’s soft tissues and vasculature. 

Despite damage occurring shortly after infection, a pet’s signs can take months or years to manifest. However, some pets show no heartworm disease signs. An affected dog’s first disease sign is usually a mild, persistent cough that progressively worsens. In addition, a dog with heartworm disease will fatigue after moderate activity, generally becoming lethargic and exercise intolerant. If heartworm disease becomes severe enough to cause heart failure, the infected dog’s abdomen will swell with fluid.

Cats may show some heartworm disease signs that are similar to the signs dogs exhibit, but your feline friend can develop other disease indicators. Cats with heartworm disease can develop wheezing, coughing, breathing difficulties, incoordination, vomiting, blindness, and seizures. In some cases, the first—and only—heartworm disease sign is sudden collapse or death.

#4: Heartworm disease can be challenging to diagnose in pets

Standard in-clinic heartworm tests are simple to run and provide results in fewer than 10 minutes. However, these tests have limitations, which can make an accurate diagnosis difficult. In-clinic heartworm tests only detect adult female heartworms, which means that false negative tests can occur if:

  • The heartworm population is all male
  • The heartworms are too immature
  • Too few adult female heartworms are present to produce enough detectable antigen

False negative test results are a possibility because of the number and type of worms present. Therefore, at your pet’s annual wellness exam, your veterinarian will perform routine heartworm testing, which is critical to diagnosing this disease in the earliest stages.

#5: Pets’ heartworm disease treatment is much more difficult than prevention

To ensure your pet is protected from contracting this disease, a number of heartworm preventives are available. Oral chewable tablets, topical applications, and injections can defend your pet against heartworm disease, and may also protect against fleas, ticks, mites, and intestinal parasites.

Administering heartworm preventives is a cinch compared with treating the disease. To eliminate the adult heartworms, an arsenic-based medication series is injected deep into your dog’s lumbar muscles. These injections can cause pain and nausea, and your dog must be inactive during treatment—usually several months—and for up to eight weeks after the final injection. Adverse effects can occur during the recovery period and potentially prove fatal. As the worms die, they can trigger a pet’s anaphylactic response, or form clots within your pet’s blood vessels.

No approved heartworm disease treatment exists for cats. The only feline heartworm treatment is supportive care for their disease signs. 

Heartworm disease is a real threat to your pet’s health, and can prove fatal if left untreated. Learn which heartworm preventive is best for your furry pal. Contact our Sixes Animal Hospital at BridgeMill team to discuss parasite preventives for your four-legged friend and schedule their annual heartworm disease test.