Heartworm and Tick-Transmitted Disease Testing

Preventative care from heartworms is vital to ensuring your pet’s overall health.

Heartworm is a potentially fatal condition all dogs are at risk for – not only those that go outside frequently. Although heartworm disease is less common in cats, it can be even more deadly for them if they get infected. Thus, pets need regular testing to detect the presence of heartworms and treat it before it becomes fatal. If you want to be proactive, contact us at 416-537-9677.

How is heartworm transmitted?

Heartworm is transmitted by mosquitoes, which we all know are not limited to the outdoors! One single bite from a mosquito infected by another animal with heartworm can easily transfer the parasite to your pet. The larvae develop within the skin and enter an infected pet's bloodstream. Once mature, they grow to be 10-15 cm long and habituate in the heart, which can lead to severe illness and clinical signs of heart disease. If you notice a swollen belly, consistent coughing, fatigue, and/or drastic weight loss in your pet, they may have heartworm.

What happens during a heartworm testing procedure?

To test for heartworm, we will take a blood sample and perform an antigen test to detect specific heartworm proteins (antigens). Adult female heartworms release these antigens into the dog's bloodstream. Another test detects microfilariae (immature heartworms). However, the earliest microfilariae can be detected in a dog's bloodstream is about 6 months after the initial infection.

How can I prevent heartworm in my pet?

Heartworm disease is easily preventable with appropriate medication. Our recommendation for most dogs is a safe and effective monthly chewable deworming medication. Our primary cat parasite prevention medications also protect cats from heartworm disease. If your pet has not been in for a visit during the past 12 months, please book an appointment with us, and we can discuss the best plan for your pet!

Practice information

Bloorcourt Veterinary Clinic

  • Mon
    8:00am – 8:00pm
  • Tue
    8:00am – 8:00pm
  • Wed
    8:00am – 1:30pm & 3:00pm – 8:00pm
  • Thu
    8:00am – 8:00pm
  • Fri
    8:00am – 8:00pm
  • Sat
    9:00am – 3:00pm
  • Sun
    Closed (Sundays & Holidays)

After-Hours Emergencies

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Find us here:

1074 Bloor Street West Toronto, Ontario, M6H 1M6
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For after-hours emergencies, please call: