Heartworm Fact Sheet

From: American Heartworm Society |  heartwormsociety.org

Heartworm Testing 1-2-3

1.  Why should I have my pet tested for heartworm?

  • Heartworm disease is a serious, progressive disease. The earlier it’s detected, the easier it is to treat.
  • There are often few, if any, signs of disease when a dog or cat is infected with heartworms, so detecting their presence with a heartworm test is important.

  2.  What is a heartworm test?

  • A heartworm test is simple and only requires a small blood sample from your pet.
  • A heartworm test works by detecting the presence of heartworm proteins.
  • The test may be read right at the clinic or sent out to a laboratory.
  • If a pet tests positive, further tests may be ordered.

3. When will my pet be tested for heartworm?

  • Yearly testing is the standard of care and is recommended by the American Heartworm Society even for pets on a heartworm preventative.
  • If a pet is showing signs of heartworm disease, such as coughing or stress during exercise, your veterinarian may order a test.
  • A heartworm test may be part of screening before surgery to help reduce the risk of complications.
  • Your veterinarian may test your pet before giving heartworm medication for the first time.

Ask your veterinarian if you have additional questions about heartworm testing or the important role it plays in managing the health of your pet. And in addition to thinking about the 1-2-3 of testing, remember to “Think 12.”

  • Test for heartworm every 12 months.
  • Give heartworm preventive 12 months a year.

Fact Sheet

It Only Takes One Bite

The mosquito is a small but mighty pest that most of us encounter when the weather turns warm and we spend more time outdoors. And because fur doesn’t stop mosquitoes from biting cats and dogs, they get attacked too. Unfortunately, there’s more at risk for pets from mosquito bites than the itching we endure. Because mosquitoes transmit heartworm disease, just one bite can be deadly to a pet.

1.  How do dogs and cats get heartworm disease?

  • There’s only one way – through a mosquito bite. It cannot be spread from one pet to another.
  • Mosquitoes become infected by biting an animal that has the disease.
  • The infected mosquito then bites a dog or cat and passes microscopic, infective larvae to them.
  • If the pet is not on a heartworm preventive all year, the larvae mature and multiply, causing damage to the heart and lungs.

2. Is it true cats don’t get heartworm disease?

  • Cats can get heartworm disease from a mosquito bite, just like dogs. It is true that cats tend to have significantly fewer adult heartworms than dogs when infected, but the infection is no less serious.

3.  Can indoor pets get heartworm disease?

  • Yes, mosquitoes frequently get inside our homes. It only takes one bite for a cat or dog to become infected, so any exposure to mosquitoes – inside or outside – puts a pet at risk.

4. How can I prevent my pet from getting heartworm disease?

  • The best way to prevent this potentially fatal disease is to use and keep your pet on preventive all year.
  • It’s also important to have your pet tested once a year.
  • Talk to your veterinarian if you have any questions about heartworm disease and how best to protect your pet.
  • Heartworm preventative medications also prevent intestinal worm problems in your pet.  Some heartworm preventative medications protect against more kinds of intestinal worms than other heartworm preventatives do, so ask your veterinarian whether your pet is on the one that is the most protective. You also have the option to place your pet on a  heartworm preventive medication that will also protect your pet from flea problems. It is important to discuss all these options with your pet’s veterinarian.

Mosquitoes in Winter?

In the dead of winter in parts of the country where the mercury drops below the freezing point and it snows often, owners are probably not seeing mosquitoes.

But that doesn’t mean the threat of heartworm disease goes into hibernation.

Preventing heartworm can be as important in the winter as it is in the summer.

  • Heartworm medicine works by killing the parasites that your pet picked up the previous month. If you stop giving it in the fall or early winter, the parasites might remain and cause an infection.
  • In many regions, the weather remains mild and mosquitoes continue to bite and cause heartworm disease.
  • If you live in a cold climate, but travel with your pet to warm places, you may expose your pet to the threat of heartworm infection.
  • Finally, getting the timing of when to stop and start giving heartworm medicine right is much more difficult than staying on a regular monthly schedule. And while prevention is inexpensive, treatment is not.

You may not see mosquitoes buzzing around in the middle of winter, but the threat of heartworm disease hasn’t disappeared.

Protect your pet — every month, all year round.

No Crystal Ball

Why pets need year-round heartworm protection

If only veterinarians had a crystal ball that could reveal exactly when and where heartworm was going to pose a threat to every pet in the country, they could counsel pet owners accordingly. However, crystal balls are in short supply, and weather and environmental conditions that are conducive to heartworm transmission are impossible to predict. For example, who would have predicted that the winter of 2012 would be—as the U.S. National Climatic Data Center has confirmed—the fourth warmest winter in more than a century? Meanwhile, in the past six years, the U.S. has experienced the most extreme negative and positive temperatures on record.

Across the country — from east to west and north to south — balmy winter weather is creating ideal conditions for an early crop of mosquitoes. And for pets, mosquitoes are more than a nuisance; these pesky little blood-sucking beasts are responsible for transmitting deadly heartworm disease.

Heartworm:  impossible to predict

A nationwide incidence survey conducted by the American Heartworm Society in 2010 confirmed that heartworm incidence and its risk factors are impossible to predict. Multiple variables, from microclimates to the presence of wildlife carriers, cause rates of infection to vary dramatically, even within communities. Because these factors are so variable, we never know when mosquitoes will emerge in the spring or how late into fall they’ll hang around.

Protect your pets

Heartworm is a serious disease that threatens the lives of infected dogs and cats. Fortunately, heartworm prevention is relatively inexpensive and easy to administer. And because neither you nor your veterinarian can predict when or where your pet might be exposed, the American Heartworm Society recommends that you Think 12: (1) get your pet tested every 12 months for heartworm and (2) give your pet heartworm preventive 12 months a year.

Think 12 and you won’t need a crystal ball!

Don’t Try to Predict—Protect

Mosquitoes Thrive in Drought

Weather is always changing and hard to predict. One year, rains are torrential and the next there’s a drought. Many people know that mosquitoes thrive in wet years and breed in wet places. But did you also know that a lack of rainwater doesn’t stop the pesky mosquito from thriving and reproducing in the U.S.? These tiny insects are highly adaptable creatures and easily find other places to breed.

And that means, despite a drought or deluge, your pets are always at risk of getting heartworm disease.

Mosquitoes Are Persistent

When drought conditions exist, many people assume mosquitoes and the diseases they carry are also gone. But despite dry conditions or lack of rainfall, there are plenty of breeding grounds, wherever you live.

While some mosquitoes breed and hatch in response to rainfall, others prefer old tin cans, tires, or they like to lay eggs in birdbaths. In urban areas, many breeding havens are man-made. When it’s very dry, say experts, these pests will search out watered lawns, garden features and underground storm systems to lay their eggs.

Mosquitoes can also carry disease, despite a drought. In humans, West Nile virus doesn’t disappear during droughts. And heartworm, which is transmitted through mosquito bites to pets, is also ever-present.

Heartworm disease is devastating. It can lead to severe lung disease, heart failure, organ damage and death. Both cats and dogs can develop heartworm from the bite of one infected mosquito. That’s why the American Heartworm Society recommends that you Think 12: (1) get your pet tested every 12 months for heartworm and (2) give your pet a heartworm preventive 12 months of the year.