The heartworm disease, also called dirofilariasis is a fatal disease caused by Dirofilaria immitis, a foot-long parasite.



Those parasites live in the hearts, lungs and blood vessels in dogs. The heartworms can cause heart failure, damage to the arteries and lung diseases. Dogs are known to be natural hosts for heartworms.
If heartworms get to live inside the dog, can easily mate and produce offspring. Their number can increase up to 300 worms, if the dog is untreated. That is why prevention is the best option.

How is transmitted?

The heartworm disease can only be spread by infected mosquito. This disease can be transmitted if adult female heartworm is already living in a dog. When is producing baby worms is known as microfilaria. The microfilaria circulate in the blood stream.Then is developing and maturing into larvae over a period of 10-14 days, and when the infected dog is bitten by the mosquito, the mosquito grabs these baby worms.
If the infected mosquito bites another dog, the larvae set down on the surface of the dog’s fur or skin, entering the new host with the help of the infected mosquito.

When the larvae is inside the new host, the larvae matures into adult heartworms. It takes approximately 6 months the larvae to become an adult heartworm. Those new developed heartworms can live for 5 to 7 years in your fury friends. This can cause internal damage of the heart, lungs and blood vessels. During the mosquito season the number of worms can increase in the infected dog due to the long life of the heartworms.

Symptoms of heartworm disease

It may take several years before dogs show some signs of infection. (in the early stages the dogs may show or may not show symptoms).
Usually by the time the dog shows any clinical sign, the heartworm disease is well advanced.
Symptoms of heartworm disease include:
decreased appetite, weight loss, lethargy, soft dry and persistent cough, blood in urine, breathing distress, weakness or anemia.

When the disease progresses, the dog’s belly might look swollen because of the excess fluid in his or her abdomen. If the number of heartworms is large, they can block the blood flow of the heart’s vessels. This could lead to a cardiovascular collapse or heart failure.
This life treating illness is known as ‘’ Caval Syndrome ’’.

dog at veterinary

Tests for heartworm disease

As mentioned above the heartworm disease is a very serious and life threating disease. If it is detected and confirmed in the early stages, the chances for recovering are better. The presence of a heartworm can be tested only by a small blood sample of your dog.

Other ways to diagnose the disease is serological test for antigens to heartworms, chest x-rays (in order to see if there is a presence of heart or lung damage), echocardiography (in order to see if there is heart enlargement or presence of worms in the heart and associated blood vessels)


If your dog is diagnosed with severe heartworm disease your vet may give you antibiotics, pain relievers, drugs for improving the heart function, diuretics for removing the excess fluid in their lungs, and special diets.
The health of a lot of dogs who have the heartworm disease may improve, by showing weight gain, improved appetite, and renewed vitality, but might need a lifetime treatment for heart failure treated by using diuretics or other heart medication such as beta-blockers, cardiac glycosides and ACE-inhibitors, followed by special low-salt diets.

Most Asked Questions About Heartworm Disease:

Is heartworm disease common in dogs?

The disease is widespread in many areas, particularly where mosquitoes are prevalent. It’s more common in regions with warmer climates.

How can I prevent heartworm infection in my dog?

Preventing heartworm infection involves using heartworm prevention medications, which are available in various forms, including monthly tablets, topical solutions, and injections.

What are the treatment options?

Treatment for this disease can be challenging and risky. It typically involves a series of injections to kill adult heartworms. The treatment process may also include medications to manage side effects and complications.

Heartworm Prevention Medications

Heartworm prevention is the most effective way to protect your dog. These medications are available by prescription from veterinarians and should be administered regularly, especially in areas with a high risk of heartworm transmission.


Treatment for Infected Dogs

If your dog is diagnosed with the disease, treatment can be complex and costly. It’s crucial to follow your veterinarian’s guidance for a successful outcome.

Lifestyle and Environmental Considerations

Reducing your dog’s exposure to mosquitoes, such as using mosquito nets or keeping them indoors during peak mosquito activity, can help lower the risk of infection

Safeguarding Your Canine Companion Against Heartworms

The disease is a serious threat to dogs, but it’s also preventable. By understanding the risks, symptoms, and treatment options, you can protect your furry friend from this potentially fatal condition. Remember that heartworm prevention is the best approach, so consult with your veterinarian to determine the most suitable preventive measures for your dog. With a proactive approach, you can keep your canine companion safe and healthy.

You as an owner can prevent your dog from getting heartworms.
All you need is to consult with your veterinarian
and test your adult dog for this serious and potentially fatal disease every six months.

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