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Mark Hale, DVM

1661 E. Mt. Gilead Road

Bolivar, Missouri 65613






            A topic that is relevant to the onset of warmer weather is Heartworm Disease.  Heartworms (Dirofilaria immitis) are parasites, primarily of canines, that are spread by mosquitoes.  This is one of the most dangerous diseases your pet can contract.  Once a canine is bitten by an infected mosquito, the heartworm larvae moves through the bloodstream to the heart.  There it matures and reaches a length of 6-12 inches.  After maturity, the female heartworm starts to reproduce so that the disease can be spread to other animals.  Felines can also get heartworms, but they seldom reproduce in felines.

The most common symptoms of heartworm disease are coughing, exhaustion or exercise intolerance, fainting spells, weight loss and swelling of the legs.  These symptoms are all due to the heart failure the parasites are causing.

Diagnosis of the condition is made by a blood test to detect the heartworm larvae.  Alternately, an "antigen test" may be used.  Early diagnosis is the key to successful treatment outcomes.  Medical treatment usually involves hospitalization, multiple doses of adulticides and strict exercise restriction for four to six weeks.  This treatment is fairly expensive and some pets have severe reactions to the dying parasites in their bloodstream and can even die following treatment.

Fortunately, heartworm disease is completely and easily preventable.  There are flavored treats that are given monthly which contain the medication to kill heartworms in their very early stages, as well as assorted other intestinal parasites.  These products may only be used in dogs that are known to be negative for heartworms, either by a blood test or by their young age.  Year-round protection is recommended for the most effective control.

If your pet is not currently on heartworm preventative, or if you just have questions regarding your pet's health care, please schedule an office visit with Dr. Hale.