Is heartworm contagious?

If your dog starts coughing and loses appetite randomly, then it is high time to make a blood test. It is very possibly that your beloved pet may be infected with heartworm. Veterinarians say that heartworm disease in dogs is very dangerous for them. However, is heartworm contagious for people? Let us check it out.

Is heartworm contagious?

What is a heartworm?

Dog heartworm is also called dirofilaria immitis. Actually it is a parasitic worm that spreads from host to host through mosquitoes bites. Dirofilaria immitis is a kind of filarial worm, a small thread-like worm that causes filariasis. The best host for it is a dog. However, it often infects other animals.

Happy dog is running

The other hosts of heartworm are:

  • Reptiles;
  • Cat;
  • African leopard;
  • Coyote;
  • Fox;
  • Beaver;
  • Ferret;
  • Sea lion;
  • Wolf.


Adult parasites often live in lung arteries, as well as in the heart. Therefore, heartworm injures tissues and the lung vessels. Infrequently, adult heartworms travel to the right heart and the great veins during heavy infections. Heartworm disease results in somber disease for the host, with death characteristically as the consequence of congestive heart breakdown.

Symptoms and signs

Heartworms in dogs initially remain completely unidentified. At the beginning of the disease it is similar to other diseases of the respiratory tract and the heart, making it more difficult to diagnose.

In three months after the parasite enters the body, the dog starts to cough. This is due to the fact that foreign bodies (worms) get deep in the lungs, thus, interfering with normal breathing. Furthermore, they also cause allergic inflammatory reaction in the thorax.

Symptoms and signs of heartworm

Then dogs tend to become lethargic, lose appetite, and cough becomes deeper with heavy breathing. Vomiting with blood clots is also possible. If such symptoms are detected, treatment should be started as soon as possible.

At this stage, development of renal and liver failure can also start.

In the later stages of the disease the dog practically ceases to walk, and when breathing its chest expands to unusually large sizes.

Is heartworm contagious?

Almost all patients are interested whether dirofilariasis is contagious. Since it is transmitted only after the bite of a mosquito, the infection cannot be transferred directly from the dog to other family member.

Heartworm in dogs

After the diagnosis was confirmed by doctors, it is necessary to make the appropriate treatment. Otherwise, more severe diseases may cause, which would be more difficult to handle than dirofilariasis.

Can people be infected with heartworm?

In most cases, people may accidentally be infected with dirofilaria immitis. Such an infection is always mechanical, because the larvae enter the body through the bite of an insect. The following groups of people may get heartworm disease oftener than the others. They are:

  • Hunters and fishermen;
  • Summer residents and agricultural workers;
  • Pet owners;
  • Tourists;
  • Employees of forestry and fishery;
  • People who live near the stagnant lakes and rivers.

Hunters and fishermen

The disease affects people regardless of age and gender. The considerable part of patients belongs to 30 to 40 years age group.

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To verify the presence of Dirofilaria immitis in dogs, pharmacological suggest manufacturers using different tests.

There are rapid tests that owner of the dog can make at home. Testing is carried out with the help of a special tool, which makes a small blood sample. In 2-3 minutes the device determines the result of the analysis based on the presence of antigens.

Please keep in mind that if Dirofilaria immitis larvae did not come from the subcutaneous layer into the circulatory system (this period lasts for approximately three months) no test will have show the necessary result.

You can also use laboratory methods. In severe cases, x-ray or ultrasound is needed to detect heartworms.


Dirofilariasis is treated relatively easily if it is diagnosed in time. If worms are found in the dog`s heart, veterinarians will give you the necessary drugs to destroy adult heartworms.

Depending on the severity of the disease your dog may need hospital treatment for two months. This is owing to the fact that some parts of dying heartworms may enter the heart valves, scoring them with bunch. Emergency surgical care will be necessary in this case.

A heartworm

Be sure to simultaneously use drugs that stimulate the heart, kidney and liver failure.

As long as the treatment is not completed, it is required to restrict the mobility of the dog to avoid creating undue stress on the weakened heart.

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