Most dog owners have heard of heartworm. It is a potentially fatal condition in which tiny parasites known as heartworms clog a dog’s heart and pulmonary arteries, eventually leading to heart failure.
Fortunately, there are a number of options available to prevent Heartworm in your dog.
What Causes Heartworm?
Dogs acquire heartworm infection via the bite of a mosquito that is carrying heartworm larvae, or microfilariae. The mosquito bite transfers the immature heartworms into the dog’s bloodstream, and over time, those worms begin to mature. They develop into young adult worms in around 90 days and then make their way into the dog’s heart. Three months later, the worms have reached sexual maturity and start to produce their own microfilariae, which are then taken up by a mosquito with a blood meal. The immature worms must undergo a period of development in the mosquito’s body before they can infect another dog.
As adults, heartworms spend their entire lifespan in a dog’s heart and neighboring blood vessels and can grow up to fourteen inches long. It is not uncommon for dogs in advanced stages of the disease to have hundreds of worms present in their hearts.
Symptoms of Heartworm
Dogs suffering from heartworm disease show a range of symptoms including a persistent cough, decreased appetite, weight loss, difficulty breathing, fainting spells, anemia, and exercise intolerance. Dogs with a heavy worm burden often develop heart failure with fluid accumulation in the abdomen leading to an obviously swollen belly. It may be several years after infection before these symptoms develop; in the early stages of infection, your dog may not show any signs of heartworm disease.
When a dog presents with a case of suspected heartworm, the first thing a vet will do is order a blood test. This test will confirm the presence of heartworm by looking for blood proteins, or antigens, produced by the adult worms. Another type of test looks for microfilariae in the blood. If a test is positive, then the next step is further blood tests and a chest x-ray to assess the severity of the disease. This will allow the vet to plan an appropriate treatment protocol.
Treating Heartworm Disease
Most dogs with heartworm can be treated successfully, although there are risks associated with treatment. There are fewer complications in dogs in the early stages of the disease; dogs with advanced forms of the disease may have residual damage to their heart. Treatment involves a series of injections under the care of a veterinarian, along with other medications such as anti-inflammatory drugs or antibiotics.
Heartworm disease is serious and progressive. The key to protecting your dog is twofold. Firstly heartworm infection can be avoided through the use of preventative medications and yearly heartworm tests. There are a number of such products; veterinarians can advise on a suitable product for an individual pet’s lifestyle. Secondly, early diagnosis and treatment usually results in a better outcome with fewer long term effects on a dog.
Content reviewed by a veterinarian.