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Jacksonville, NC 28546 US

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Heartworm Prevention FAQ

Our Jacksonville Veterinarian Answers Common Questions Regarding Heartworm Prevention

What is heartworm disease and how is it transmitted?

Heartworm is just what it sounds like, worms that live in the heart, lungs and blood vessels of an infected animal. Heartworms are thin and can grow up to 12 inches long. As the worms grow and multiply they block blood flow to the heart and other crucial organs.

If a mosquito takes blood from an infected animal, the microfilaria, or “baby worms” circulating in the bloodstream are also ingested by the mosquito. When the infected mosquito bites another animal, it deposits infective larvae on the animal’s skin. The larvae can enter the new host through the open wound of the fresh mosquito bite.

Once inside a host, the microfilaria grow to maturity in approximately 6 months. Mature heartworms can live up to 7 years in dogs and up to 3 years in cats. Pets can be infected with new microfilaria over and over again during the course of the mosquito season.

There are no mosquitos where we live. Is my pet still at risk?

Heartworm disease is present in all 50 states. Though some geographical areas at a higher risk for heartworm than others, infected mosquitos and infected pets can travel everywhere, transmitting the disease wherever they go.

What are the symptoms of heartworm?

Unfortunately, many infected pets show no signs at all until the disease is advanced. In some cases, the first sign is cardiovascular collapse. If they present at all, symptoms differ in dogs and cats.

Heartworm symptoms in dogs:

  • Mild, persistent cough
  • Unusual fatigue
  • Reluctance to exercise
  • Decreased appetite
  • Weight loss
  • Swollen abdomen
  • Pale gums
  • Dark or bloody urine

Heartworm symptoms in cats:

  • Coughing
  • Vomiting
  • Asthma-like episodes
  • Difficulty walking
  • Fainting or seizures
  • Unexplained weight loss

Is Heartworm disease preventable?

Heartworm disease is not 100% preventable, but monthly use of a heartworm preventative from your veterinarian is highly effective. Heartworm medication does not prevent the transmission, instead, it eliminates any larval parasite that may be present before it matures and puts your pet’s health at risk. Medication is available in pill form, topical medication and injection.

Why does my pet have to be tested if it’s already taking heartworm medication?

Yearly testing confirms whether or not the preventative is working. If your pet does test positive, early detection increases the chances of a full recovery. Pets that haven’t previously been on a preventative, or those who’ve had a lapse in their medication, should be tested immediately and again in 6 months. Once it’s been confirmed that your pet is heartworm-free, annual testing is recommended.

What happens if my pet tests positive for heartworms?

Heartworm treatment is aggressive, expensive, and stressful and can require a lengthy hospital stay. Your pet must be closely supervised by a veterinarian while the arsenic-based drug is administered. Dying heartworms may obstruct the lungs or blood vessels so the animal must be closely monitored in case of complications. Preventing heartworm disease is much easier than treating it.

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  • "Dr. Corry has always gone above and beyond for the care of our family's pets."
    John / Jacksonville, NC

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