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Heartworm Protection

The Importance of Heartworm Protection for Your Dog or Cat
Just about everyone has heard of heartworm and is somewhat familiar of its very serious and often lethal effects. But surprisingly, not everyone takes preventative measures to prevent heartworm in their pets. In fact, The American Heartworm Society (AHS) estimates that only 55% of dogs in the U.S. are currently on a heartworm preventive, leaving 27 million dogs at risk of acquiring heartworm disease.

Heartworm is extremely dangerous and not to be taken lightly. It is prevalent in all 50 states, and on every continent except Antarctica. It is easily transmitted and contracted. Once in its host, the parasite rapidly multiplies and grows, invading the chambers on the right side of the heart and the arteries in the lungs. Treatment for heartworm disease can mean weeks of discomfort, and pets that go untreated will die.

What are the Symptoms of Heartworm?
Because the heartworm parasite goes through various life stages before reaching full maturity, early detection is very difficult. These parasites can live in its host for years before symptoms appear and can reach lengths of up to 12 inches.

Dogs: While recently infected dogs may not show any signs or symptoms, heavily infected dogs show the following symptoms: A consistent cough, fatigue and aversion to physical activity, coughing up blood, loss of appetite and weight loss. The most extreme symptom in very advanced cases can be congestive heart failure.

Cats: Because cats are not a natural host for the heartworm parasite, there are far fewer cases of feline heartworm disease, but it is still possible and preventative measures should still be taken. Symptoms of heartworm in cats are very difficult to read and often appear strikingly similar to feline asthma or bronchitis. These symptoms include: gagging, strained breathing, vomiting, fainting spells, back-leg paralysis, inactivity and weight loss and are associated with a syndrome called Heartworm Associated Respiratory Disease (HARD).

Detecting Heartworm Disease

General heartworm detection is usually done through blood testing, though false negatives can occur with infections prior to seven months. Therefore, regular heartworm testing is optimal.

Heartworm infection may also occasionally be detected through ultrasound and/or x-ray images of the animal's heart and lungs where the adult parasites dwell.

Heartworm Disease Treatment

Cats: Currently, there is no successful Heartworm Disease treatment for cats. Treatment involves killing off the worms, and cats do not deal well with dead worms. They are usually able to battle off the disease naturally, and as the saying goes, the cure is often worse than the disease. Prevention is the best way to address heartworm in cats. While medication can deal with the symptoms, prevention will combat further parasite growth. 

Dogs: In dogs, Heartworm Disease treatment requires diligence and follow-up. The different stages of the parasite involve individual treatment. Medication and plenty of rest will usually cure most cases of Heartworm Disease, though treatment can be somewhat uncomfortable. In very advanced cases of Heartworm Disease where the dog’s heart is directly affected, surgical removal of the parasite may be necessary.

Heartworm Prevention

Preventing Heartworm Disease is far easier than curing it. North Shore Animal League America urges you to protect your pets – even your indoor cats, as they too are susceptible to the mosquito bites that cause Heartworm Disease. Since cats cannot be properly treated for Heartworm Disease, prevention is imperative.

Prevention is the key to keeping your pets free of the parasite – even if they encounter the disease carrying mosquito. Preventative medications come in daily and monthly oral and topical forms and can be obtained from your veterinarian along with a heartworm checkup. Heartworm prevention is safe, inexpensive and easy to follow and should be maintained all year long – NOT just in the summer months.

North Shore Animal League America urges you to consult with your veterinarian and see which heartworm preventative is best for your pet. The alternative can be expensive, painful and even deadly. Please be responsible and get your heartworm prevention today! A healthy pet is a happy pet!


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