Heartworm is a disease that a dog contracts from parasitic roundworms that reside within the heart and pulmonary arteries. Symptoms of the disease range from mild to severe, and many different factors play into how affected a dog is and how sick they get. The good news is that heartworm is curable in all but the worst cases. The best news is that heartworm disease is preventable.
Let’s take a closer look at what heartworm disease is, how to prevent it, and how it is treated if a dog has it.
What Is Heartworm?
Heartworms are parasitic roundworms that can affect both dogs and cats. Scientifically referred to as Dirofilaria immitis, these worms are contracted from mosquitoes who bite them, taking a blood meal and leaving behind larvae of the worms in the process. Not all mosquitoes are infected with heartworms, and not all geographic areas have heartworm-infected mosquitoes.
Dogs offer a host body for heartworm parasites to complete their life cycle. Once mature, these tiny parasites work their way into the heart, lungs, and other blood vessels. At full maturity, worms can measure up to 1 foot long, and it’s possible for a single dog to be infected with hundreds of worms.
Without treatment, dogs can have serious health complications, including death, so it’s extremely important to prevent this disease from occurring. If your dog has already contracted heartworms, expedited treatment from a veterinarian is critical for a positive outcome.
Symptoms of Heartworm
Not all dogs have noticeable symptoms of heartworm. Blood tests conducted by your veterinarian are necessary for a definitive diagnosis, but here are a few warning signs that your dog may be infected:
- Persistent cough — Dogs with heartworm often exhibit a persistent, dry cough. This is often one of the first signs of illness in an otherwise healthy dog.
- Lethargy — Exercise intolerance or avoidance altogether are common symptoms of heartworm. If your dog seems more tired than usual or is no longer interested in walks, it could be a sign of illness.
- Weight loss — Some dogs with heartworm lose their appetite.
- Swollen belly — Heartworm disease can lead to heart failure, which causes fluid build-up in a dog’s abdomen.
- Difficulty breathing — Advanced cases of heartworm can cause dogs to have respiratory issues due to the parasites invading their pulmonary arteries and reducing blood supply to the lungs.
Treatment of Heartworm
Treatment protocols for heartworm are determined according to the disease’s severity, but three common steps are involved.
- Medication — Heartworm treatment involves several different medications. Injections of Melarsomine are often used to kill the adult worms after rounds of Doxycycline (used to kill the symbiotic bacteria associated with the worms) and steroids like Prednisone are used to reduce unwanted side effects. Heartworm preventative medication will be given to prevent juvenile worms from causing more extensive infection. Other medications may be given to your dog to relieve symptoms.
- Surgery — In severe cases, dogs require surgery to fully remove heartworms from the lungs and heart vessels. Unfortunately, this doesn’t always work, and many dogs with severe worm burdens may
- Exercise restriction — This is a vital part of heartworm treatment that is required before, during, and up to two months after treatment.
Treatment for heartworm takes a long time and happens over the course of months. Injections of medication must be given at specific intervals, and exercise restrictions may remain in place for several months. For this reason, it is much better to prevent heartworm disease in the first place.
Heartworm Prevention
Whether your dog needs seasonal or year-round prevention from heartworms will depend on where you live. There are several FDA-approved heartworm prevention medications that can be obtained with a prescription from your veterinarian. Some are topical, others are oral, and most are monthly doses. Many heartworm preventatives also offer protection against other intestinal parasites, along with fleas, ticks, and mites.
The recommendations from the American Heartworm Association for disease prevention are as follows:
- Give your pet heartworm prevention medication year-round.
- Have your dog tested annually for heartworms so treatment and diagnosis are prompt if an infection occurs.
- Discuss the best heartworm preventative treatments with your veterinarian.
Conclusion
Heartworms can cause serious complications for dogs, which is why it is best to prevent infections from occurring. In most cases, dogs can be cured of heartworm, and their long-term prognosis is good. In severe infections, though, heartworms can be fatal. If you are concerned about heartworm infection in your dog or have questions about disease prevention, talk to your vet about the best course of action.
Related Read:
- Can Dogs Overdose on Heartgard? Facts & FAQ (Vet Answer)
- Heartworms in Dogs: Signs, Causes & Treatments (Vet Answer)
Featured Image Credit: Lindsay Helms, Shutterstock
