Preventing and Treating Heartworm Disease in Dogs

Heartworm Disease in Dogs

Heartworm disease is serious and can be fatal. It spreads when mosquitos that carry heartworm larvae infect animals through their bites. 

The severity of heartworm disease in dogs depends on the number of worms present in their bodies and how long the worms have been there. The fitness of dogs and how quickly you’re able to get them treatment will also have an impact on the prognosis.

Read on for the lowdown about this unpleasant and nasty condition.

How Dogs Contract Heartworm Disease

When it bites, a mosquito can transmit the larvae of the organism Dirofilaria immitis, known as heartworm, into the body. These larvae then navigate their way to the infected dog’s heart and lungs. 

Heartworms can then grow to be 30cm or a foot long. The whole process takes around 6 months or more. Although the symptoms of heartworm disease can be very serious, there is some good news:

  • Heartworm disease can be curable if treated in time and correctly
  • The disease tends to only occur in certain geographical areas
  • Dogs cannot transmit the disease to humans 

Places Where Heartworm Disease in Dogs Is Most Common

The heartworm is most prevalent in places with tropical and subtropical climates. For example, there are pockets of southern Europe where dogs could be at high risk. Conversely, there’ve been no reported outbreaks of the disease in the United Kingdom. 

There have been plenty of heartworm diagnoses across the USA. These commonly happen along the Atlantic and Gulf Coasts as well as in the Ohio and Mississippi river basins.

You should check with your vet about the heartworm situation where you live. You should also pay careful attention if you plan to travel with your dog to places where there are instances of heartworm disease.

The Signs Your Dog May Have Heartworm Disease

Symptoms of heartworm disease in dogs will vary and to an extent depend on how far gone the condition is. Early common signs include:

  • A cough
  • An intolerance of exercise
  • Poor body condition

Vets can carry out an antigen test to see if dogs have heartworm. The disease tends to have 4 distinct clinical stages or classes. The type of treatment will vary accordingly.

Class 1: 

Dogs tend to display no symptoms at all or only suffer from a few minor issues such as an occasional cough. 

Class 2:

Dogs may experience coughing, fever and be unable to tolerate exercise. A vet might also detect an abnormal heart sound. Mild anemia and protein loss could show up in further medical tests. Radiographs might show dilated pulmonary arteries and right heart enlargement.  

Class 3:

Dogs may suffer from:

  • Breathing difficulties, a cough and a deterioration in coat quality
  • Weight loss, lethargy and lack of appetite
  • Coughing up blood
  • Fluid accumulation and a pot-bellied appearance

Tests could also show similar clinical symptoms to those in Class 2. 

Class 4:

At this stage, Caval Syndrome is how vets define heartworm-positive dogs. All the clinical signs of Classes 2 and 3 can be present but by now there may be so many heartworms that they block the blood from reaching the heart. Treatment is now likely to be too late and the focus of care will be to make the dog as comfortable as possible.

Concerns About the Potential Dangers of Heartworm Disease

You should talk to your vet about any worries you might have about heartworm disease. These could relate to:

  • Where you live
  • Where you’re planning to travel to 
  • Suspected symptoms 

Your vet will be able to carry out a quick blood test to see if your dog has heartworm. They can do this even if you are giving your pet preventative heartworm medications.

If there’s a positive result, your vet will normally carry out a second test. This acts as confirmation that the first antigen test was genuinely positive. Other tests can include:

  • A urinalysis
  • X-rays
  • A total and complete blood cell count

All these kinds of tests can help to determine the best course of treatment along with the most likely prognosis. 

In mild to moderate cases when treatment is timely, dogs can often make a good recovery. If the condition develops for too long, a dog can suffer certain short and long-term complications. 

Treatment for Heartworm Disease in Dogs

Your vet will try and stabilize the dog’s condition. They will prescribe medication to kill off the developing heartworms. This typically involves a series of 3 injections over 4 weeks.

Your dog will typically have to undergo a period of hospitalization during this period. Your vet may have to prescribe further drugs: 

  • To prevent any adverse reaction to the death of the heartworms
  • For pain medication and to stop nausea or stomach upsets 

In very severe cases, the vet may try to remove the heartworms through surgery under a general anesthetic. The procedure is very risky. It’s worth noting that most dogs at the Class 4 Caval Syndrome stage are likely to die. 

The Prevention of Heartworm Disease in Dogs

Even if treated once for heartworm disease, dogs will still need medication to stop them from getting reinfected.

You can prevent heartworm disease in dogs with monthly heartworm medicine prescribed by a vet. Your dog will normally have to undergo a test for heartworms before your vet prescribes the medication.

Although highly effective, heartworm preventatives are not 100 percent effective. One of the key reasons for this can be that owners do not adhere to administering the correct doses of medication on time. They may also believe that they successfully administered the medication when in fact the dog did not ingest it. 

You may therefore need to get your dog tested regularly even if your pet is receiving preventative medicine. The cost of preventing heartworm disease over a dog’s lifetime is about the same as it can cost to treat the disease just once. 

Talk to an Expert Now About Your Heartworm Concerns

Preventative treatment for heartworm in dogs is a sound financial investment. It can also save a lot of heartache and suffering. 

If you’d like to talk through anything connected to heartworm disease in dogs, please get in touch with us now. Immediate online consultations are available with a qualified vet. We can also offer you further peace of mind with our straightforward, hassle-free, pet insurance.

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