How Heartworm Can Affect Your Pup
Veterinarian Reviewed by Dr. Janice Huntingford, DVM on January 30, 2019
Posted in Dog Coughing
As a dog owner, you’re probably familiar with numerous intestinal parasites, such as the tapeworm or hookworm, but another common parasitic worm doesn’t affect your dog’s intestines—it affects its heart and lungs.
Heartworm is a dangerous disease caused by the parasite of the same name, and preventing it should be at the top of every dog owner’s priority list.
What is heartworm?
Heartworm disease is a very serious health condition that is quite common in dogs. In some cases, heartworm can be fatal. In others, it can make a dog’s life much harder and uncomfortable.
Heartworms are parasitic worms that infect the heart, lungs and blood vessels of the animals they enter. Over time, these worms can grow and reproduce, causing internal damage along the way. This growth and reproduction can lead to significant cardiovascular and respiratory system damage, as well as total organ failure.
Heartworm is most commonly transmitted via mosquitos. Adult heartworms create baby worms that can be transmitted from an infected animal to a mosquito when the mosquito bites it. Then, when a mosquito bites an uninfected animal, it can transmit those slowly maturing heartworms to it.
Some areas of the world are more affected by heartworm-infested mosquitos than others. However, it is possible for your dog to be infected just about anywhere. If you’re traveling, it is wise to do research about the risks of heartworm and take precautions accordingly.
After a dog has been infected, it can take nearly half a year for baby worms to grow into adults and start causing problems within the heart and lungs. Adult worms can reach around 12 inches in length. Heartworms can live for around seven years in dogs, making them particularly dangerous because of their longevity.
This also means heartworms can be difficult to spot until it is too late, as maturing worms have probably been in your dog for months, if not years, when it starts displaying symptoms. The longer the disease is able to progress, the worse symptoms your dog may display.
The risks of heartworm
Heartworm is not always an easy disease to identify, nor is it easy to treat. Many dogs die from this disease because owners do not notice or let the disease go untreated.
Some of the most common signs of heartworm include:
- Weight loss
- Decreased appetite
- Swollen belly due to fluid accumulation
- Weak pulse
One of the biggest risks of heartworm is a major heart problem, such as cardiovascular collapse. This is a very serious ailment that causes blockages within the heart and can be identified by labored breathing, pale gum and dark-colored urine. Inflammation of the blood vessels can also occur as a result of heartworm and lead to clots, causing heart failure.
Another issue associated with heartworm is lung problems including difficulty breathing. A cough is one of the most common early symptoms because heartworms begin to crowd the heart and lungs. Over time, your dog’s cough and its ability to breathe may become worse and more dangerous.
You may also notice your dog becoming resistant to exercise. It may be unable to sustain exercise for the same length of time or at the same intensity as it used to. This is because it has a harder time breathing and may have restricted blood flow that makes it more difficult to transmit oxygen throughout the body.
If your dog does contract heartworm, you should verify the diagnosis through testing at your vet. If the tests come back positive, you’ll need to be prepared for some changes in your dog’s life as you help it get rid of the heartworms and manage its symptoms.
One of the most important changes is a limit on the exercise your dog gets. Normally, physical activity is great for dogs, but it can actually be very damaging to dogs with heartworm. Dogs with heartworm need to be much less active than normal. This is because, as heartworms die, they break into smaller pieces that can get lodged in the cardiovascular system. Rigorous exercise can cause these pieces to become stuck, leading to further complications.
Additionally, your dog will need to endure a treatment plan designed to manage symptoms of heartworm disease and remove all living heartworms. This treatment may come with side effects and risks, depending on how severely your dog’s disease has progressed. Not all treatments will be effective, but the earlier the disease is caught, the more likely your dog is to recover.
Because heartworm is so difficult to treat and comes with many complications, prevention is the best way to maintain your dog’s healthy and happy quality of life. Make sure to administer heartworm medicine to your dog as prescribed by your vet. Additionally, your dog should undergo annual heartworm testing to verify it does not have the condition.
With careful attention to your dog’s health and regular monitoring, your dog should be safe and remain heartworm-free. Always stay cautious of heartworm and its dangers and discuss more prevention options with your vet if you live in an area where heartworm is more common.
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Janice Huntingford, DVM, has been in veterinary practice for over 30 years and has founded two veterinary clinics since receiving her Doctor of Veterinary Medicine at the Ontario Veterinary College, University of Guelph. She has studied extensively in both conventional and holistic modalities. Ask Dr. Jan