Do you hear that buzzing in your ear? It’s the annoying sound of a mosquito, all too common at this time of year. But did you know that mosquito bites, although irritating to you, pose a significant health threat to your pets?

Heartworm disease is on the rise, and with over 1 million dogs now infected in the US, it’s important to get the facts on this risk to our pet’s longevity. The Pet’s Place Animal Hospital wants to make sure our readers are aware of the risks of this deadly disease, and the importance of year-round prevention.
 

What is a heartworm?

Heartworm is a type of roundworm that infects dogs, cats, and wildlife via the bite of an infected mosquito. Adult heartworms live in the heart and pulmonary arteries of infected animals and cause significant damage to these organs and other body systems. If left untreated, heartworm infection leads to the animal’s death.
 

The Heartworm Life Cycle

To get to the heart of the matter, it’s important to understand how heartworm is spread. The heartworm life cycle is long and complex, which makes diagnosis quite challenging.

• A mosquito bites an infected pet or other animal and takes up the larvae, or microfilariae into its body.

• The microfilariae develop inside the mosquito's body for 10-30 days.

• The mosquito then bites another uninfected pet and transmits the microfilariae to that pet’s bloodstream.

• The microfilariae develop further over the course of several weeks, finally making their way to the pet’s heart and pulmonary arteries, where they mature into foot-long, adult worms.

• After 6-7 months of the initial infection, the adult heartworms begin to reproduce and release new microfilariae into the pet’s bloodstream. The pet can now spread the disease further with a new mosquito bite.
   

Signs and Treatment

Signs of heartworm disease are a bit different in cats and dogs, and can mimic signs of other respiratory illnesses. In general, signs include lethargy, coughing, exercise intolerance, and wheezing. Unfortunately, because of their anatomy and immune system response to heartworms, one of the only signs of heartworm disease in cats is a respiratory emergency followed by sudden death.

Treatment of heartworm disease in dogs is long, expensive, and not without risk. It involves injections administered over the course of several weeks to months, and likely requires hospitalization to monitor the effects of treatment. The medication kills the adult heartworms, and as they die they may fragment into pieces that can block the arteries to the lungs or heart, causing a respiratory or cardiac emergency. Exercise restriction is also a part of the treatment, to avoid complications.

Unfortunately, medical treatment for cats is not available. Veterinarians typically recommend treating the cat’s respiratory signs and related complications. Surgical removal is possible with a specialist, however, this surgery is complicated, risky, and costly, and therefore is not often recommended.
 

Prevention of Heartworm Disease

It’s clear that because of the prevalence of heartworm, the risk to a pet’s health and life, and the cost and difficulty of treatment, heartworm disease prevention is an easy answer.

Monthly preventives are safe, effective, and inexpensive when compared to the cost of diagnosis, treatment, and disease management. There are options for monthly chews or tablets, and many of them also prevent intestinal parasites such as hookworm and whipworm.

All preventives kill the microfilariae circulating in the bloodstream. Because it takes the microfilariae 51 days to mature into adult heartworms, it’s important to interrupt this process. Therefore, giving heartworm preventives on a strict schedule is imperative. And, with iCal or other calendaring apps, remembering to give preventives on time is truly a no-brainer!

Ask us today about how to best prevent heartworm disease in your pet. You’ll rest easier, even with that annoying mosquito buzzing in your ear.