Whether your dog spends significant time outdoors or just goes outside for a routine walk, they are susceptible to heartworm disease. Heartworm can develop into a serious condition, so taking the necessary steps to prevent your furry friend from getting heartworms is essential to their health.

Understanding Heartworm

Heartworm is a preventable disease that is often fatal without treatment. Dogs and cats are among the top hosts for this parasite, but wild animals can contract heartworm as well. Heartworms are foot-long worms that can live in the heart, lungs, and blood vessels of a mammal and cause severe damage to their body’s organs. Heartworms can live in your pet’s body for up to seven years, but it is not contagious from one mammal to another.

Heartworms were first discovered in dogs in the United States in 1856. Today, cases have been found in every state. 

Symptoms are not evident until the disease has progressed significantly. Pets with heartworm disease may require surgical treatment to repair damaged arteries and other vital organs depending on how far the disease is allowed to progress.

What Causes Heartworms in Dogs?

Mosquitos spread heartworm in dogs. Even if your dog spends most of its time indoors, it can still develop heartworm disease.

Mosquitoes pick up microfilaria, or heartworm larvae, from a heartworm-infected wild animal or pet. When a mosquito carrying that microfilaria bites your pet, the microscopic larvae on its mouth transfer into the dog’s bloodstream. 

Larvae spread through the bloodstream and make their home on the right side of the heart. As the worms grow and reproduce, they damage your dog’s heart, lungs, and arteries. As a result, heartworms often cause death or lifelong health problems without immediate and effective treatment.

What Are the First Signs of Heartworms in Dogs?

Depending on your dog’s health at the time of infection, you may not notice heartworm disease symptoms. Typically, heartworm doesn’t show initial symptoms until the disease reaches later stages. The first heartworm symptoms your dog will display are a mild, persistent cough and exercise intolerance.

Four classes are used to define heartworm disease severity and symptoms.

  • Class One: This class often shows no symptoms. Some dogs may develop a mild cough.
  • Class Two: Minor coughing becomes persistent in Class Two. Your dog will also exhibit mild exercise intolerance.
  • Class Three: For a dog with Class Three heartworm disease, exercise intolerance and lethargy increase, and their pulse weakens. They’ll also make abnormal breathing sounds and have appetite decreases resulting in significant weight loss. Some dogs may faint regularly, and you may notice bloating from heart failure.
  • Class Four: In the most extreme class, heartworm infection becomes caval syndrome. The cardiovascular system begins to shut down. Common symptoms are pale gums, brown urine, significant difficulty breathing, and death.

Diagnosing and Testing for Heartworm

Heartworm treatment is a lengthy and fatiguing process that some dogs cannot safely undergo. As with most diseases, early detection and treatment facilitate a better prognosis for your pup.

Animal clinics diagnose dogs with heartworm using blood tests, including:

  • Heartworm antigen tests
  • Heartworm snap tests

Other diagnostic tools include x-rays, ultrasounds, and echocardiograms. This imaging inspects the heart, lungs, and other vital organs and systems that heartworms inhabit.

What Is a Heartworm Antigen Test?

Heartworm antigens (proteins) develop in your dog’s bloodstream within seven months of the initial infection. Heartworm antigen tests are blood tests that check for these proteins in the blood. If your dog is positive for heartworm, this test will indicate microfilaria despite showing no obvious symptoms.

Your dog may need multiple antigen tests to determine whether larvae are present in the bloodstream. Most antigen tests detect adult worms easily. However, present antigen antibodies and low worm burden counts can create misdiagnoses.

What Is a Heartworm Snap Test?

A heartworm snap test is a fast and effective blood test that detects heartworm disease even at low worm burden counts. Its high accuracy makes it popular in many animal clinics.

In many cases, additional testing is not necessary. However, some cases may warrant additional antigen tests to determine how safe treatment is.

Veterinarians and other medical animal carers take a sample of your dog’s blood, add the sample to the rapid test, and apply the buffer. Within several minutes, the test indicates whether your dog has heartworm disease.

Treating Heartworm

Heartworm treatment can be hard on your dog. For that reason, many vets highlight the importance of preventative care.

Professionals determine the best course of action for your pet depending on the stage of heartworm infection, age, and other factors. If your pet has caval syndrome, your vet may recommend keeping them comfortable during their last days versus undergoing expensive treatment that they may not survive.

Treatments include chewable pills and intramuscular shots. Your vet may also prescribe steroids and antibiotics to fight infection. Surgical removal of heartworms may be necessary in extreme cases.

How to Prevent Heartworm in Dogs

Heartworm prevention medication is the leading choice for individuals wanting to protect their dog against heartworm. Individuals should also use safe, FDA-compliant mosquito repellants when spending time outdoors with their dogs.

You should avoid walking your dog in swampy areas or places with standing water. These areas are common mosquito breeding grounds and may increase your pet’s risk of developing heartworm. It’s also best to keep your dog indoors or limit their outdoor activity at dawn and dusk when mosquitoes feed.

Choose Penny Paws Animal Clinic for Effective Heartworm Solutions

Penny Paws Animal Clinic is Texas’s leader in heartworm prevention and treatment for dogs and cats. If you suspect your pet has heartworm disease, contact us or visit one of our locations in Texas today.