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.
Diagnosing
Heartworm
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.
