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Heartworm – What Every Pet Parent Should Know

Posted on 22 July 2025
Heartworm – What Every Pet Parent Should Know

Heartworm is a serious disease caused by worms that live in the heart, lungs, and blood vessels of dogs and cats. It’s spread by mosquitoes  and just one bite can infect your pet.

The good news is: it’s easy to prevent!

What is Heartworm?

Heartworm is caused by long worms that live in the heart and lungs. These worms can grow up to 30cm long and cause serious problems like heart failure, lung disease, and even death if left untreated.

Dogs are the most common hosts, but cats can get it too. Even though it’s less common, it can still be life-threatening.

What Are the Symptoms?

In dogs, signs may include:

  • A soft, dry cough
  • Tiredness or less interest in walks and play
  • Weight loss
  • Trouble breathing or swelling in the belly (in serious cases)

In cats, signs can be more sudden and include:

  • Coughing
  • Vomiting
  • Trouble breathing
  • Sudden collapse or even death in some cases

How Do Pets Catch It?

Heartworm spreads through mosquito bites. When a mosquito bites an infected animal, it picks up baby worms. Then, when it bites your pet, it passes the worms on. Over several months, those worms grow into adults and start causing damage.

Heartworm Lifecyle

 

How Do We Diagnose and Treat It?

Dogs: We do a simple blood test to check for heartworm. If they test positive, they’ll need a special treatment plan and lots of rest. Treating heartworm is a difficult process which is why prevention is always better than cure. 

Cats: Heartworm is harder to detect in cats, but we can run tests and take X-rays if needed. There’s no approved treatment for adult heartworms in cats.

How Can You Protect Your Pet?

You’ve got two great options:

  1. Monthly preventatives
    These can come in tablets, chews, or spot-on treatments. They must be given on time every month. Even missing just one day can put your pet at risk.
  2. The yearly injection (ProHeart 12)
    This is given by your vet and protects your dog for a whole year. Bonus: it has a 3-month “reach-back,” so if you’ve missed a monthly dose, this injection can help cover the gap.

Is your pet protected? 

Call the clinic on 9632 9622 and our lovely receptionists can ensure your pet is covered!

Why Choose Great Western Animal Hospital?

We’re your local trusted vets in Sydney’s western suburbs, and we’re here to keep your pets safe, happy, and healthy. Whether you need help with preventatives, testing, or just some advice, we’ve got your back.

Call us to book:(02) 9631 9322 or book online.

Tags:Pet SafetyProactive Pet CareDogHealth AdviceCatClient Information
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