Warm weather is here at last, mosquitoes are coming out to play and heartworm season is upon us.  Even dogs that spend most of their time indoors can be at risk since mosquitoes, the carriers of heartworm disease, often find their way into our homes.  Is your dog protected?

What are heartworms?   A heartworm is a parasite that infiltrates a dog's bloodstream.  When an infected mosquito takes a blood meal from a healthy dog, the heartworm larvae are transferred to the dog through the insect's saliva.  The tiny heartworms travel through the dog, eventually maturing and living in the dog's heart and pulmonary (lung) arteries.  These adult worms can be as long as 10-12 inches and live up to 5-7 years.  Blood tests cannot typically detect this parasite until the worms are around 7 months old. 

What are the signs of heartworm disease?  Clinical signs may not surface until a dog has been infected for several years.  The worms slowly damage the heart and blood vessels, especially when they reside in the lungs.  Mild but persistant coughing, exercise intolerance (tiring easily), decreased appetite and weight loss may be signs that a dog is infected.  In some cases, the worms may cause a life threatening blockage (throumboembolism) in the blood vessels of the lungs or heart , possibly leading to heart failure.

Is this disease treatable?  Heartworm disease is treatable in dogs.  Unfortunately treatment is expensive and potentially dangerous.  Depending on the severity of the case and the weight of the infected dog, costs may reach as high as $800-$1000.  Before treatment can begin, the dog needs to undergo testing (i.e. bloodwork, x-rays) to make certain the liver and kidneys are functioning well enough to handle the treatment and to assess the damage to the lungs and heart.  Over the next several months, the patient will need multiple doses of parasite-killing medication, hospitalization for treatment and follow-up testing.  As the worms die off, they can break loose and cause blockages creating the potential for deadly thromboembolisms.  Even after treatment is complete, the patient must be kept on strict exercise restriction for up to six months to help prevent these life-threatening blockages.  Treatment for heartworm disease is necessary to save the life of the dog but is expensive, dangerous and requires long term follow-up care. 

Operation Heartworm Disease Prevention:  All of this can be avoided with the use of monthly heartworm prevention.  There are many types of heartworm prevention on the market.  Your veterinarian can help you find the right prevention for your pet.  Most of these preventatives also have the added benefit of controlling the most common intestinal parasites, some of which are transmissible to humans.  Because of this extra parasite prevention, increased pet travel, Ohio's changable weather and the prevalence of mosquitoes, we recommend keeping your dog on heartworm prevention year round.  As the saying goes "an ounce of prevention is worth a pound of cure".  For more information on heartworm diseae, you can talk to your veterinarian or visit www.heartwormsociety.org.