April is Heartworm Awareness Month—a perfect time to learn about a serious (but preventable!) disease that affects pets across the country. Whether you’re a new pet owner or have had furry family members for years, understanding heartworm disease can help you keep them safe and healthy year-round.
What Is Heartworm Disease?
Heartworm disease is caused by parasitic worms that live in the heart, lungs and blood vessels of infected animals. Over time, these worms grow and multiply, causing damage to the heart and lungs.
In dogs, symptoms may include:
- Persistent cough
- Fatigue after mild activity
- Weight loss
- Difficulty breathing
If left untreated, heartworm disease can lead to heart failure and even death.
Cats can also get heartworms, though the disease often presents differently and can be harder to diagnose. In some cases, the first sign may be sudden collapse or respiratory distress.
How Is It Transmitted?
Heartworm disease is spread through the bite of an infected mosquito, NOT contact or proximity with an infected animal.
When a mosquito bites an infected animal, it picks up microscopic heartworm larvae. These larvae develop inside the mosquito and are then passed to another animal through a future bite. Once inside your pet, the larvae mature into adult heartworms over several months.
Because mosquitoes are the carriers, any pet is at risk—even those who spend most of their time indoors.
And while many people think of mosquitoes as a summer problem, that’s not always the case here in Ohio. In recent years, milder winters mean temperatures don’t stay cold long enough to fully eliminate mosquito populations. That means the risk of heartworm transmission can continue well beyond the warmer months.
How Is It Treated?
Treatment for heartworm disease is difficult, expensive and physically demanding for your pet.
For dogs, treatment involves:
- A series of injections to kill adult heartworms
- Multiple medications to manage symptoms and prevent complications
- Strict rest and limited activity for several weeks or months
While treatment is generally effective, it does carry risks, especially as worms die and break down in the body.
For cats, there is currently no approved treatment to eliminate adult heartworms. Care focuses on managing symptoms and providing supportive treatment.
Prevention Is the Best Protection
The best way to protect your pet from heartworm disease is through consistent, year-round prevention.
Here’s what you can do:
- Give monthly heartworm prevention prescribed by your veterinarian
- Test your dog annually to ensure early detection
- Limit mosquito exposure by getting rid standing water around your home or yard, and keeping pets indoors during peak mosquito activity times like dawn and dusk
Heartworm prevention is simple, affordable and often protects against other parasites, too.
Take Action This Heartworm Awareness Month
Heartworm disease is serious—but it’s also preventable. This April, take a moment to check in on your pet’s protection plan.
- Is your pet up to date on their heartworm prevention?
- When was their last heartworm test?
If you’re unsure, now is the perfect time to reach out to your veterinarian. Protecting your pets from heartworm is important—not just this month, but all year long.