Heartworms in Dogs: Truth vs Legend

Heartworm-Disease-In-Cats-And-Dogs

Heartworms look like long spaghetti wrapped around your dogs heart. Not too pretty! Heartworm disease is a very serious disease in pets. If not treated it can be fatal! It is caused by foot-long worms (heartworms) that live in the heart, lungs and associated blood vessels of affected pets, causing severe lung disease, heart failure and damage to other organs in the body. One of our staff member recounts his scary hearworm story.

” When I bought my puppy Zara I neglected to get her heart worm prevention treatment and boy did I regret it when she turned 6. Don’t make the same mistakes that I made, Ready my story below!”

Heartworm disease affects dogs, cats and even ferrets, but heartworms also live in other mammal species, including wolves, coyotes, foxes, sea lions and—in rare instances—humans. Because wild species such as foxes and coyotes live in proximity to many urban areas, they are considered important carriers of the disease.

Heartworm – Life Cycle

Zara’s STORY – “WE DIDN’T WANT TO SPEND EXTRA MONEY WHEN SHE WAS YOUNG ON PREVENTATIVE TREATMENT. WHEN SHE TURNED 5, DURING A ROUTINE VET VISIT, THEY TESTED HER FOR HEARTWORMS. TO OUR SURPRISE, IT CAME BACK POSITIVE. HER HEART LOOKED LIKE THE PHOTO BELOW.”

How is it transmitted? Those Pesky Mosquitos

It’s as simple as a mosquito bite in the middle of a summer night! The mosquito plays an important role in the heartworm life cycle. Adult female heartworms living in an infected dog, fox, coyote, or wolf produce microscopic baby worms called microfilaria that circulate in the bloodstream. When a mosquito bites and takes a blood meal from an infected animal, it picks up these baby worms, which develop and mature into “infective stage” larvae over a period of 10 to 14 days. Then, when the infected mosquito bites another dog, cat, or susceptible wild animal, the infective larvae are deposited onto the surface of the animal’s skin and enter the new host through the mosquito’s bite wound. Then after the bite the worm begins to grow and harm you dog little by little.

What are the signs of heartworm disease in dogs?

During the early stages of the disease, most dogs show few if not any symptoms. Through the years the symptoms will progress.

Signs of heartworm disease may include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss.

zara’s story continued… ” she was having a hard time breathing. The family was worried she wouldn’t make it. We ended up having to spend over $3,000 in emergency medical treatments to kill the adult and baby worms.”

How significant is my pet’s risk for heartworm infection?

Many factors must be considered, even if heartworms do not seem to be a problem in your local area. Your community may have a greater incidence of heartworm disease than you realize—or you may unknowingly travel with your pet to an area where heartworms are more common. Heartworm disease is also spreading to new regions of the country each year. Stray and neglected dogs and certain wildlife such as coyotes, wolves, and foxes can be carriers of heartworms. Mosquitoes blown great distances by the wind and the relocation of infected pets to previously uninfected areas also contribute to the spread of heartworm disease (this happened following Hurricane Katrina when 250,000 pets, many of them infected with heartworms, were “adopted” and shipped throughout the country).

The fact is that heartworm disease has been diagnosed in all 50 states, and risk factors are impossible to predict. Multiple variables, from climate variations to the presence of wildlife carriers, cause rates of infections to vary dramatically from year to year—even within communities. And because infected mosquitoes can come inside, both outdoor and indoor pets are at risk.

For that reason, the American Heartworm Society recommends that you “think 12:” (1) get your pet tested every 12 months for heartworm and (2) give your pet heartworm preventive 12 months a year.

What do I need to know about heartworm testing?

Heartworm disease is a serious, progressive disease. The earlier it is detected, the better the chances the pet will recover. There are few, if any, early signs of disease when a dog, cat or ferret is infected with heartworms, so detecting their presence with a heartworm test administered by a veterinarian is important. The test requires just a small blood sample from your pet, and it works by detecting the presence of heartworm proteins. Some veterinarians process heartworm tests right in their hospitals while others send the samples to a diagnostic laboratory. In either case, results are obtained quickly. If your pet tests positive, further tests may be ordered.

When should my pet be tested?

You can test dogs annually during routine visits. This helps ensure you’re doing everything you can to prevent a problem before it gets worse. If you have a puppy that’s under 7 months old you can start heartworm prevention without a test. Definitely consult your local veterinary or chat live with a vet right now through Pet Health Store’s Live chat feature.

View Full ArticleIs Heartworm Prevention Worth It

What happens if my dog tests positive for heartworms?

No one wants to hear that their dog has heartworm, but the good news is that most infected dogs can be successfully treated. The goal is to first stabilize your dog if he is showing signs of disease, then kill all adult and immature worms while keeping the side effects of treatment to a minimum.

Here’s what you should expect if your dog tests positive:

  • Confirm the diagnosis. Treatment is not easy and it’s very expensive. So be sure your dog really has heartworms. Once a dog tests positive on an antigen test, the diagnosis should be confirmed with an additional—and different—test. Because the treatment regimen for heartworm is both expensive and complex, your veterinarian will want to be absolutely sure that treatment is necessary.
  • Restrict excessive movement. Basically anything that causes movement should be restricted. This requirement might be difficult to adhere to, especially if your dog is accustomed to being active. But your dog’s normal physical activities must be restricted as soon as the diagnosis is confirmed, because physical exertion increases the rate at which the heartworms cause damage in the heart and lungs. The more severe the symptoms, the less activity your dog should have.
  • Stabilize your dog’s disease. Deal with any other small issues before you get into the heatworm treatment. Before actual heartworm treatment can begin, your dog’s condition may need to be stabilized with appropriate therapy. In severe cases of heartworm disease, or when a dog has another serious condition, the process can take several months.
  • Start the treatment. Once your veterinarian has determined your dog is stable and ready for heartworm treatment, he or she will recommend a treatment protocol involving several steps. The American Heartworm Society has guidelines for developing this plan of attack. Dogs with no signs or mild signs of heartworm disease, such as cough or exercise intolerance, have a high success rate with treatment. More severe disease can also be successfully treated, but the possibility of complications is greater. The severity of heartworm disease does not always correlate with the severity of symptoms, and dogs with many worms may have few or no symptoms early in the course of the disease.


zara’s happy ending ” now zara is a happy pet and she has no problems breathing. our family has decided to put her on an all natural food diet and she’s healthier than ever”

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