All pet owners have heard of heartworms, but you may not know the nitty gritty behind these nasty critters. In this blog, you’ll find out what heartworm disease is, how pets can get it, what happens to pets that are heartworm positive, and how to prevent heartworm disease.

What is it?

Heartworm disease is a serious and potentially fatal disease in cats and dogs. It is caused by foot-long worms that live in the heart, lungs, and associated blood vessels of affected pets.

A real image of what heartworms look like inside of a dog who did not survive heartworm disease.

How do pets get heartworms?

Pets get heartworms from mosquitos. Cats and dogs are known as “definitive hosts” because heartworms can grow and reproduce in them.

When a mosquito bites and takes blood from an infected animal, it picks up baby worms, which develop and mature into “infective stage” larvae over 10 to 14 days. Then, when the infected mosquito bites another pet, the infective larvae are deposited onto the surface of the animal’s skin and enter the new host through the mosquito’s bite wound.

Once inside a new host, it takes approximately 6 months for the larvae to mature into adult heartworms. Once mature, heartworms can live for 5 to 7 years in dogs and up to 2 or 3 years in cats. Because of the longevity of these worms, each mosquito season can lead to an increasing number of worms in an infected pet.

Heartworm Facts

What will happen if my dog or cat gets heartworms?

In the early stages of the disease, many dogs show few symptoms or no symptoms at all. The longer the infection persists, the more likely symptoms will develop.

Symptoms may include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss. As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen.

Dogs and cats with large numbers of heartworms can develop a sudden blockage of blood flow within the heart leading to a life-threatening form of cardiovascular collapse. This is called caval syndrome, and is marked by a sudden onset of labored breathing, pale gums, and dark bloody or coffee-colored urine. Without prompt surgical removal of the heartworm blockage, few pets survive.

How can I prevent my dog or cat from getting heartworms?

Preventing heartworms is easy. Get an annual heartworm test and use monthly heartworm preventatives to protect your pet!

Schedule an appointment today to make sure your pet is covered!