What is heartworm?

Photo by Eric Ward on Unsplash

What exactly is heartworm disease?

Heartworm disease is a serious and potentially fatal condition in cats and dogs. It is caused by adult heartworms that can measure up to a foot long (~30cm). Heartworms damage the heart, lungs and associated blood vessels, and this damage can be permanent (even after the heartworms have been cleared).

How is heartworm spread?

Heartworm is spread by mosquitoes. In an infected dog, adult heartworms produce ‘baby’ heartworm larvae that circulate in the dog’s blood. When a mosquito bites an infected dog and takes a blood meal, it also ingests the heartworm larvae.

Once the larvae are inside a mosquito, it develops over 10-14 days into an “infective stage” larvae. When the mosquito bites a dog or a cat, the infective larvae are deposited into the bitten animal’s bloodstream. The larvae travel to the heart, and take 6 months to mature into adult heartworms.

An adult heartworm can live for 5-7 years in a dog, and 2-3 years in a cat. That is a lot of time for them to damage a pet’s vital organs!

Is heartworm disease relevant in Singapore?

Mosquitoes are commonplace in Singapore, and even more so during the dengue season. This means that cats and dogs in Singapore are very vulnerable to heartworm. Unfortunately, even indoor-only animals are not spared. Mosquitoes can fly as high as 60m, which is the equivalent of a 21-story building!

What are the signs of heartworm disease?

The signs of heartworm disease can range from mild to severe – depending on how long the pet has been infected, the number of heartworms present, and whether there are other health conditions present. Pets with early-stage disease may not show any symptoms. In the later stages, symptoms include:

  • Coughing, increased panting and/or breathing effort
  • Lethargy
  • Exercise intolerance, asthma-like attacks
  • Weight loss.

Pets can eventually develop heart failure. In rare cases, sudden death can occur without any prior symptoms.

Can other domestic pets (e.g. rabbits, guinea pigs) get heartworm?

Rodents like rabbits, guinea pigs, hamsters and chinchillas cannot get heartworm.

What if I suspect that my dog or cat has heartworm disease?

If you are worried that your pet might have heartworm, bring him or her to a vet as soon as you can! It is easier to diagnose heartworm in dogs than in cats. For dogs, your vet can do a “SNAP test” to check for adult heartworms. It is much harder to diagnose heartworm in cats. Your vet will have to do several tests (e.g. x-rays and blood work) to arrive at the diagnosis. This highlights the importance of heartworm prevention!

How can I prevent heartworm in my pet cat/dog?

Your pet should be on heartworm preventatives regularly, to protect them against heartworm. Cats: Cats can start on heartworm prevention anytime! You can simply purchase Broadline or Revolution for Cats here.

Dogs: You may have seen heartworm preventatives being advertised by online retailers. However, it is dangerous to simply buy the preventatives from these sellers and feed it to your dog. For some dogs, a heartworm test has to be done before starting them on heartworm preventatives. It is dangerous to give a heartworm preventative to a heartworm-positive dog. The preventative will kill the worms and cause a heart-blockage, which is fatal.

If your pet dog fulfills certain conditions, you can purchase/top-up heartworm preventatives from us without a video call or a heartworm test. Safety is our utmost priority! If you would like to find out if your dog is eligible for heartworm, simply click on this link and answer a series of simple but important questions!