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Spring 2024

Defending your pet: Understanding and preventing heartworm disease

Crucial heartworm prevention strategies to safeguard your pet's health.
Picture of By Nationwide
By Nationwide

Heartworms are stealthy parasites that can kill your pet, transmitted by a bloodthirsty insect that can make outdoor activities borderline intolerable all summer long. If that reads like the script for a horror movie, take heart: With knowledge and preventive care, your pet can avoid this deadly parasite – and you can skip the expense and difficulties of treating an infection.

While heartworms can infect cats (and other animals), our feline friends aren't ideal hosts for the parasites and typically aren’t as seriously affected. For dogs, though, heartworms are a serious problem.

What are heartworms?

The heartworm is a parasite that matures in the heart, lungs and blood vessels of its host animal. Mosquitoes carry the immature stages of the worm, which they pick up when feeding on animals already infected. When the mosquito bites again, it sends the immature worms into the new victim, and the cycle starts over.

Not scary enough for you? Heartworm disease is present in all 50 states and around the globe, and as the climate warms, mosquito season and range are expanding, making heartworm a year-round threat.

Heartworm disease can be invisible at first, as the parasites grow and reproduce with little outward signs, even while doing serious damage to the lungs, heart, liver and/or kidneys. As the infection grows or the worms mature, symptoms may appear, including:

  • Chronic cough
  • Lethargy
  • Exercise intolerance
  • Loss of appetite, weight loss
  • Abdominal swelling

Treating heartworm disease

Heartworm treatment can take months and is very hard for both the dog and the family. It involves doses of injections to kill the worms that live in the dog’s blood vessels, lungs and heart. The injections are painful, so pain medication is also generally prescribed.

Additionally, because of the way the medication works, the dog cannot be allowed to get excited. The dog’s blood now contains dying and decomposing worms. Any excitement would increase the dog’s heart rate, which then pumps that matter through the veins and could lead to clotting or heart failure. So pets who bark at delivery drivers, get excited to go outside, whine when the doorbell rings or even just like to play, usually need to be crated and sedated to stay calm enough for the duration of treatment.  

If there were ever a case to be made that “an ounce of prevention is worth a pound of cure,” heartworm disease makes it, no dispute.

Prevention is key

Fortunately, heartworm disease can be prevented with medications that eliminate immature parasites before they can become adults. They are safe and highly effective when given as instructed. Monthly heartworm preventives given by mouth are the most common but topical and injectable options are available, and some are combined with other parasite treatments. Talk to your veterinarian to decide which preventive is best for your dog.

Veterinary healthcare teams typically recommend annual heartworm tests before prescribing preventive medication. This test is just too risky to skip if there are any doubts that a pet isn’t 100% heartworm-free. If a dog already has heartworm disease, giving these preventives without treatment to eliminate the infection could cause more harm. Heartworm treatment is also safer if an infection is caught early.

Available discounts on heartworm preventives

Heartworm preventives can take a bite out of your pet care budget, but Nationwide members can save on these necessary medications thanks to partnerships with Walmart, Sam’s Club and Petco.

For Walmart and Sam’s Club, take advantage of Nationwide PetRxExpress. Simply log on to your account at my.petinsurance.com and download your pet insurance ID card. It’s good for many veterinary medications, heartworm preventives included. Ask your pet’s veterinary practice to send over the prescription electronically, call it in or give you a handwritten prescription that you can present at the counter.

Nationwide also has a partnership for saving with Petco Veterinary Services, with full veterinary hospitals, vaccination clinics and prescription services available around the country.

Heartworm is a horror story your dog can avoid, thanks to effective, safe preventive medication. Get your dog tested, save money on year-round preventive medication, and you and your will pet have nothing to fear from these dangerous parasites.
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Add-a-pet

Take advantage of your multi-pet discount when you add a pet to your policy. When covering two or three pets, you can receive a 5% discount. When covering four or more pets, you'll save 10% on your base premium. Visit the member portal to add a pet. 

Enroll a new pet
Pet care

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