Heartworms: Getting to the Heart of the Issue

Heartworms are parasites that are transmitted by mosquitoes from other infected pets and wildlife.

The Heartworm Life Cycle

Mosquitoes ingest larvae from infected animals. The larvae mature inside of the mosquito which then bites your pet. Over the next two months, the larvae continue to develop into immature adults within the tissue. It is at THIS stage that preventatives are effective. Immature adults enter the bloodstream and heart. They then take approximately 4-6 months to mature to the point where they produce their offspring (microfilariae). This cycle continues until the heartworms are treated.

How Can Heartworms Make My Pet Sick?

Dogs with heartworm infections often suffer symptoms due to adult worms clogging the vessels from the heart to the lungs. At home, you may see coughing and exercise intolerance. These symptoms often are indicative of changes to the heart, vessels, and lungs. The heart becomes enlarged, the blood vessels widen, and the lungs can become congested with worms. One of the biggest health concerns is blockage of the lungs by the worms which can lead to death.

Cats with heartworm infections experience many of the same symptoms and changes as dogs. However, due to cats’ delicate systems, just one heartworm can kill a cat!

What Do Preventatives Do?

The preventatives available through your veterinarian can only kill the DEVELOPING LARVAE. Although we call them preventatives, they do not prevent heartworm transmission. Heartworm preventatives simply prevent heartworm disease by killing the larvae before they can develop into adults. Heartworm preventatives are given monthly YEAR-ROUND to continually kill new larvae acquired from mosquitoes.

Heartworm Preventatives Available Through BGVC

Dogs: Heartgard Plus, Sentinel
Cats: Revolution
More products available through our online store!

Why and When to Test

A heartworm test indicates if the animal has mature adult worms. It takes approximately 6-8 months from an infected mosquito’s bite to heartworm maturation. So if your dog gets bitten by an infected mosquito in December, the heartworm test will not be positive until June at the earliest. This is why we recommend heartworm tests at least every 12 MONTHS (every 6 months if not taking heartworm preventative). Even if your pet is on heartworm preventative, we recommend testing as accidents happen (missed dose, pet spits pill out, pet rubs topical off) and we want to make sure that all of our patients are healthy!

What Happens If My Pet Has Heartworms?

If you have a DOG diagnosed with heartworm disease, treatment takes place over a span of at 4 months and includes strict exercise restriction. Treatment is expensive and must be closely monitored.

Click to view the American Heartworm Society's client handout outlining heartworm treatment!

If you have a CAT diagnosed with heartworm disease,unfortunately there is NO APPROVED TREATMENT of the heartworms themselves. Treatment is solely targeted to managing symptoms until as heartworm preventative slowly kills the present heartworm larvae. This treatment may include emergency visits, can span many months, is generally expensive, and even the best efforts may not prevent death.

To Sum It Up

Heartworms are transmitted by mosquitoes.

heartworm testing is recommended, even if your pet is on a preventative.

Preventatives must be given MONTHLY to be effective.

Heartworm disease can pose a LIFE-THREATENING risk to cats and dogs.

It is cheaper and safer for your pet to PREVENT heartworms, rather than to treat!

Contact us:
Email: battlegroundvet@bgvc.net
Phone: 765-742-2587