Heartworm has a complicated life cycle. Infected dogs and cats have microfilaria, an immature form of heartworm, circulating in their bloodstream.  Microfilariae are sucked up by mosquitoes when feeding on the blood of infected dogs and cats. The immature parasite develops into a heartworm larva inside the mosquito, then a single bite from a carrier mosquito can infect your pet (dog or cat). As the worms mature in the heart they can cause a physical blockage as well as thickening of the heart and associated blood vessels. In the earlystages of infection there may be no visible signs, however, infection may eventually lead to signs of heart failure (reluctance to exercise, lethargy,coughing) and even death. Dogs and cats may have heartworm infection for months or even years before they develop any of these signs. 

Heartworm is present throughout most of Australia (except Tasmania and arid areas).

Thankfully, heartworm is very easy to prevent and should form part of your pet health care routine. We have very effective preventative treatment options available including tablets, chews, spot-on's and even an annual injection for dogs administered by one of our vets. If your pet has not been on heartworm prevention we strongly recommend a heartworm test prior to starting a prevention program, followed by a repeat test 6 months after commencing.

How is heartworm infection diagnosed?

A simple 5 minute blood test done in the clinic can tell us if heartworms are present in your dog or cat. If positive, X-rays can reveal changes in the heart and lungs that are typical of heartworm disease and help us to assess the stage of the disease.

How can heartworm infection be prevented?

Dogs must be negative for heartworm first as shock and death can occur in dogs harboring heartworm if preventative medication is used. ProHeart SR-12 injection has been proven safe and effective. 

  • Daily heartworm tablets given at the same time each day for life.
  • Monthly tablets or chews given around the same date each month for life.
  • Monthly spot-ons which also cover fleas, given on the same date each month for life.
  • Yearly injection (Proheart SR12) given on the same date each year.

Is there treatment for heartworm infection?

Yes. Modern treatments are very effective in treating infestation. The treatment will vary a little depending on the stage of the disease. Treatment invloves a series of medication and injections and usually a two day stay in the surgery. The injections kill the adult heartworms in the heart. Special medication and strict confinement are necessary for a couple of months to reduce the risk of adverse reactions and shock.