An ounce of heartworm prevention is worth a pound of cure

heartwormTreatment of heartworm disease can cost as much as $1,000 for bigger dogs, much more than the cost of monthly preventive medication, notes veterinarian Melissa James. The health costs to dogs are high, as they suffer severe damage to the heart, kidneys and their overall health, and some dogs do not survive treatment. Heartworm preventive medication has the added bonus of killing other parasites that can cause illness in dogs and people, Dr. James adds. The Blade (Toledo, Ohio) (5/20)

Jody Brickner’s Brittany spaniel, Ruthie, is a survivor.

The 15-year-old first lost her home eight years ago and ended up in rescue. Then she was diagnosed with heartworm disease.

The rescue group opted to spring for the expensive treatment for the friendly orange-and-white dog, and Mrs. Brickner fell in love with her in the process.

“She is a great gal,” said Mrs. Brickner, who lives in Findlay with Ruthie and several other dogs. “Even in her age and weakness, she can still be the boss around here.”

One thing pet owners need to know is that all preventive treatment options for heartworm are much less expensive than treating the disease, said Dr. Melissa James, a veterinarian at Blanchard Valley Veterinary Clinic in Findlay, where Ruthie was treated.

“Also, once they’ve had heartworm, you can’t reverse the damage to the heart,” Dr. James said.

Both topical and oral medications are available that prevent a dog who is bitten by a mosquito carrying heartworm from getting the disease. Oral medications include both hard chews and soft chews, depending on the preference of the dog.

Adult heartworms can grow up to a foot in length and live as long as five years inside a dog. They can clog pulmonary arteries, and if there is significant infestation, the worms back up into the heart itself and eventually fill it. They cause blood clots, and the heart has to work abnormally hard to pump blood through plugged arteries. Heartworms also cause serious inflammation in the arteries that can affect the liver and kidneys.

Heartworm is a silent killer and can easily go undetected for several years, Dr. James said. Dogs don’t start to experience symptoms such as coughing, lethargy, and exercise intolerance until the disease is pretty far along.

Ruthie was given three deep intramuscular injections of Immiticide to kill her heartworms. Dogs being treated for heartworm must be kept quiet and not exercised while the parasites in their system die off.

Several treatment protocols are used, depending on the severity of the disease, which is assessed by clinical exams, radiographs, and blood work, Dr. James said.

Ruthie got one injection, followed by another injection 30 days later, and a third injection 24 hours after the second.

The cost of treatment depends on the weight of the dog and can approach $1,000 for large dogs.

Mrs. Brickner has fostered two other dogs with heartworm for American Brittany Rescue. The group reports about 10 percent of dogs it takes in have heartworm infection.

“Another one was a senior dog with a low infection,” she said. “He was treated just with Heartgard once a month for a slow kill. They felt the standard treatment would have been too hard on him.”

The third dog, Ruby, was severely infected and didn’t make it. “It had already affected her kidneys when she came into rescue,” Mrs. Brickner said. “Her appetite was very poor, and it was very sad. I paid for a treatment that was supposed to clear her blood from toxins because of the kidney failure.

“She felt better for a very short time, only a few days. Within two months of coming into rescue, she pretty much stopped eating, and we made the tough choice to let her go.”

One of the benefits of treatment with heartworm preventive is that it also kills other intestinal parasites such as roundworm and hookworm, which can be passed on to humans, Dr. James said. Some heartworm preventives also kill whipworms.

“They are transmitted via fecal matter through the skin,” Dr. James said. “You don’t necessarily have to ingest the fecal matter. If kids are playing in a yard where an infected dog has defecated, they can get the worms. And no one wants their kids to have internal parasites.”

While dog owners are thinking about preventing heartworm, they also should consider flea and tick preventives, Dr. James said. Some heartworm preventives are effective against fleas and ticks. “Although it seems like a lot of money, it’s a lot cheaper than treating the illness,” Dr. James said. “And ridding your home of fleas once your dog has brought them in is time-consuming and no fun.”

Ticks, which carry Lyme disease, already are prevalent this year, Dr. James said. According to the Companion Animal Parasite Council, 250 out of 45,376 dogs tested positive for Lyme disease in Ohio in 2012, or one in 182. Ticks can be removed by owners, but they must be careful not to crush the tick in the process because that will release the diseases it carries into the dog. It’s also dangerous for owners to burn ticks off dogs.

“They can burn them to destroy them once they remove them, but not while they are still on the dog,” Dr. James said. “I often see more damage from people trying to remove the ticks than what the tick itself has done.

“If the tick is embedded or the dog owner doesn’t feel comfortable in removing them, they should let their vet do it.”

Contact Tanya Irwin at or 410-724-6066, or on Twitter @TanyaIrwin.

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