Dog Owners Declare War on Heartworm Disease

By Lambert Vet Supply | 2/1/2019 | Posted to Dog Health

Heartgard Rx for Dogs

Heartgard® Rx is for use in dogs to prevent canine heartworm disease by eliminating the tissue stage of heartworm larvae (Dirofilaria immitis) for a month (30 days) after infection.

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Around the world, war has been declared! As your dog’s owner, you serve as his 4-Star General and Commander-in-Chief of Parasite Control. You must give the order, administer the preventative, and banish heartworm disease once and for all!

Heartworm disease threatens canine health with serious risks, but it is also one of the most treatable conditions with the proper prevention and medication. What is heartworm disease? To answer that question, the M-word must be mentioned-mosquitos! Mosquitos serve as the incubator and delivery system for many nasty human and animal diseases and infections. For dog owners, mosquitos transport one of the most dreaded conditions possible for canines-heartworm disease.

What Goes Around Comes Around
The cycle to produce heartworms takes several stages and breeders, but the mosquito starts the assault. Here’s the short version. Heartworm infected dogs, foxes, coyotes, or wolves carry microfilaria, microscopic baby worms, in their bloodstream, the result of adult female heartworms. When a mosquito bites an infected animal, it picks up these tiny worms. These baby worms mature into “infective stage” larvae in about 10 to 30 days inside the mosquito. The mosquito will pass on these infective larvae when it bites another dog or wild animal. About six months later, inside the new animal, these larvae will develop into full-fledged adult heartworms with a five to seven year life expectancy. It is possible for dogs to harbor several thousand worms in their hearts and adjacent large blood vessels when infected. The female worm (6-14 inches long and 1/8 inch wide) causes most of the damage, but a male can do his share, too, growing to half this size. Inside a dog, the adult worms will produce microfilaria, which matures to adults. If nothing disrupts the worm and mosquito cycle, canine health will spiral out of control.

Get Checked Out
Most dogs are diagnosed with heartworm disease between 2 and 8 years of age because of the time involved to produce adult heartworms. Because of this, the disease may be well advanced when found. It is rare in young dogs since the microfilariae have not had time to mature.

Unchecked heartworm disease can lead to death. Even cases managed early can seriously affect canine health. Heartworm disease overloads a dog’s heart and the major blood vessels leading to the heart and lungs with worms. This heartworm blockage reduces the blood supply to other major organs of the animal’s body, especially the lungs, liver and kidneys.

The American Heartworm Society (AHS) makes strong recommendations for ANNUAL TESTING of every dog as part of a complete heartworm prevention program. This will allow a veterinarian to catch heartworms earlier for effective management. Sadly, AHS’ estimates show only half of dogs in areas prone to heartworms receive the proper preventive medicine. This number is reduced further because only about 75% of canines receive all the required monthly doses.

Puppies, under the age of 7 months, can begin taking heartworm preventives without testing first. Testing should occur 4 to 7 months after starting the medication to determine a heartworm infection. As always, consult with your veterinarian about testing schedules and options.

An Important Canine Test
In the battle against heartworm disease, the first line of defense comes from a blood test to detect/confirm heartworm disease. Called an antigen test, it will look for specific antigens from adult female heartworms. A local veterinarian can perform these tests on-site. These tests are better at detecting female heartworms at least 7 or 8 months old, but less likely to find worms younger than 5 months old. That is one reason why starting a dog on heartworm preventative as a puppy is so important.

If a dog is diagnosed with heartworm disease, work closely with a veterinarian to tackle the problem. The vet will need to assess what stage the infection is in and look for underlying conditions, such as heart and lung damage and liver and kidney function. These problems will have to be dealt with before drug treatment can begin. A vet will monitor for side effects and a dog may be required to maintain strict bed rest or short-term hospitalization to watch for adverse results. The dog may be quite sore and stiff at the injection site so the vet may prescribe pain medication. During the four weeks it takes for the worms to die, the dog must be kept from running and playing since the dying/dead worms may migrate to the heart or lungs and cause a life-threatening blockage. Monthly heartworm preventive medicine will also be administered during this time to catch other worms in development. Abnormal symptoms during the treatment like diarrhea, coughing, vomiting and depression should be reported to a vet.

Generally, the success rate for dogs treated for heartworm is about 98 percent and most will not require additional intervention. A few will require another treatment if heartworm tests still indicate a presence six months after the initial injections. It can take months before a dog will have a negative heartworm antigen test.

Related Article: Dogs And Heartworm Disease >>

Heartworm Exhibits Health Risks at Every Stage
Most dogs do not show any early signs of the disease, which means by the time it is caught it is usually in an advanced state. Heartworm disease often displays mild and subtle canine health changes, which may resemble aging.

Stage One-Most dogs will appear healthy and happy and blood tests may even be negative at this phase. Some owners may notice a slight cough, but nothing will seem irregular for the vet even during an examination.

Stage Two-Symptoms may have progressed enough to be detected during testing. Other indicators may be fatigue after exercise or a lingering dry cough from dying worms in the lungs and fluid accumulation in the lungs. Signs of heart disease will appear on an x-ray and lab tests may show mild anemia. Urine analysis may indicate minor protein loss.

Stage Three-At this point, the disease will show up well on x-rays. Dogs will continue to cough, exhibit tiredness from exercise or avoid exercise completely. Dogs may also have trouble breathing, experience weight loss and severe vascular damage. Lab work may show acute anemia and marked urinary protein loss.

Stage Four-Untreated, this stage of heartworm disease is fatal. It will cause breathing issues, coughing, and marked exhaustion and lethargy. Heartworm disease will have impacted other organs like the lungs, kidney and liver. A dog’s stomach may look pot-bellied as his liver enlarges and fluid accumulates in the abdomen. If a dog experiences the Caval Syndrome, it will collapse in shock with dark, brown urine. Heartworms will be visible by ultrasound and blood work will be abnormal. Surgical removal of adult heartworms via an incision through the jugular vein is the only way to save this dog. If a dog manages to survive this emergency, further heartworm treatment must wait until the dog is stable.

Take the Heartworm Offensive
Every stage of treatment for heartworm disease carries some risks. The longer heartworm disease goes undetected, the more difficult it is to cure. The best defense, of course, is a good offensive attack through a regularly, applied regimen of heartworm preventive medicine designed to kill heartworms, round worms and other parasitic worms.

Five primary chemical-based treatment options exist for heartworm disease protection: Ivermectin (the primary ingredient in Heartgard Plus and several other brand names), Selamectin (the principal ingredient in Revolution), Moxidectin (the primary ingredient in Advantage Multi), Miobeymycin Oxine (used by both Sentinel and Trifexis), and Fluralaner (used by Bravecto).

Most vets agree on two things about preventive action, follow the product’s directions and administer it monthly on a regular basis AND maintain heartworm medication year-round. Cases of heartworm have appeared in all 50 states so even dogs that live in the northern United States are still at risk. Heartworm treatments are usually priced in the $30 to $40 range for a 6 to 12 month supply. Not sure what product would work best for you? Consult with your vet to get the best possible product for your canine.

So be prepared to fight the heartworm battle by taking the offensive with veterinarian-recommended heartworm disease preventatives. Take charge of your pet’s health and order heartworm’s surrender.

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The information contained in The Well Pet Post articles is not intended to replace a one-on-one relationship with a veterinarian and is not intended as medical advice. If you have a health con­cern about your pets, please consult with an appropriately-licensed veterinarian. Never dis­re­gard pro­fes­sional veterinary advice or delay in seek­ing it for your pets because of some­thing you have read on this blog or in any linked materials.
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