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Heartworm Disease in Dogs and Cats

Heartworm disease in pets is precisely what it sounds like; worms that infest the heart and pulmonary arteries. The mode of transmission of this disease is the mosquito. No dog or cat is safe from heartworm disease. In fact, a pet can become infected with heartworms anywhere and at any time. Infections have been reported in all 50 states. Mosquitoes are more prevalent in the spring and summer, but the disease can be contracted at any time of year. Amazingly, it only takes a single bite from an infected mosquito to infect a pet. Although heartworm disease is more common in dogs, it is much more deadly to cats. Heartworm disease can cause illness and can even result in death. The good news is that this disease is essentially 100% preventable!

In dogs, heartworms reside in the heart and surrounding blood vessels. This causes injury to the tissues which results in heart failure and pulmonary disease. In some cases, the worms can cause an embolus, or blockage, of other large vessels causing other organs to become affected. Severe and untreated cases can be fatal. Signs of heartworm disease in dogs are a deep cough, fatigue, lethargy, labored breathing, weight loss and distention of the abdomen.

While cats are less susceptible to heartworm infection, their body is much more sensitive to it. Cats can become severely ill or even die from only a small infection. Cats with heartworm disease may experience coughing, gagging, respiratory difficulty, lethargy, weight loss and even sudden death.

If a pet owner notices any of these signs, they should seek veterinary attention immediately. Many times, heartworm disease will produce no clinical signs, which is why prevention and regular screening is crucial.

Though heartworm disease is devastating, it is preventable. The first step is getting a pet tested. A simple blood test can reveal if a pet has been exposed to heartworm infection. Should a pet test positive for heartworm infection, additional diagnostics, such as radiographs or ultrasound, may be recommended by the veterinarian to determine the extent of the disease process. The next step to protecting a pet against heartworm disease is preventative medicine. On a pet to pet basis, the veterinarian will recommend an oral, topical or injectable preventative. Many of these preventative medications also protect pets against intestinal parasites. In most cases, a pet should be protected with medication year round.

So what if a pet does test positive for heartworm infection? Unfortunately at this time, there is no safe cure for cats due to the serious side effects, such as blood clots, it produces. Instead, cats are usually limited to supportive care such as cage rest, oxygen therapy, and steroids. However, some cases of heartworm disease in cats can resolve on their own. In dogs, newer and safer products have become available in recent years that are very effective in eliminating heartworm infection. Although, treatment of heartworm infection can produce side effects, which makes follow-up visits to the veterinarian and close monitoring of the pet vital.