Heartworm: very dangerous, but easily preventable

Let me start by saying that heartworm is disgusting. Ticks and Lyme disease get a lot of attention, but heartworm is rarely discussed, leaving a lot of pet parents confused about what it is, how it’s transmitted, how they can prevent it, and how it’s treated. A potentially fatal disease, heartworm is caused by parasitic worms in the heart and lungs and, unfortunately, doesn’t always come with symptoms. In fact, every dog that has come into the shelter with heartworm has been symptom free. How, then, can you protect your pet from this deadly disease?

Transmission

Heartworm is transmitted through the bite of a mosquito and can affect your pet regardless of their age or breed. In fact, because mosquitoes have a nasty habit of finding their way indoors, your pet doesn’t even have to be outside to get infected! Once bitten, the heartworm larvae mature in your pet’s body, sometimes growing as long as 12 inches (I did mention it was disgusting, right?). From there, an infected dog may be bitten by a mosquito and that mosquito may then bite another dog, transmitting the disease again and again and again in an endless cycle.

Prevention

Preventing heartworm is even easier than preventing Lyme disease. Unlike flea and tick preventative, which is placed on the skin of your dog’s neck and leaves a patch of their fur greasy and odd smelling for hours after, heartworm preventative is most commonly given to your pet as a chewable treat. Heartworm preventative typically comes in daily or monthly doses and, if given to your pet regularly, is highly effective at preventing heartworm. If your pet is not on a regular heartworm preventative, be sure to have your vet test your pet for heartworm prior to starting a preventative. If your pet is positive for heartworm and then given a preventative, it can be fatal.

Treatment

As part of your pet’s yearly exam, your vet will do a blood test for heartworm and tick borne illnesses. Should your pet test positive for heartworm, expect a long and expensive treatment process. While there are not currently any methods of treating heartworm in cats, most dogs are treatable and can continue to lead happy and normal lives. The treatment process consists of a series of injections that are administered to the muscles. After the treatment, dogs must remain on strict bed rest for weeks in order to prevent the dead heartworms from forming a fatal blockage of blood flow to their lungs.

The entire process is very uncomfortable for dogs and the complete recovery period can take up to two months. At the shelter, our most recent dog to go through the heartworm treatment process required several additional months of foster care after he recovered in order to learn how to trust people again. The treatment process was so traumatizing for him, he became fearful of anyone who tried to handle him and, although he was originally a friendly dog, he started to lash out at anyone who came too close.

You can save your dog from the trauma of heartworm simply by providing them a regular heartworm preventative. At this time of year, when dogs spend more time outdoors, our pets are at higher risk of contracting the disease through an infected mosquito. If your pet isn’t already on a preventative, talk to your vet today!

Alaina Goodnough is the Promotions Coordinator at Cocheco Valley Humane Society in Dover, NH. She lives in Sanford, ME with three parrots, two cats, and two dachshunds. She can be reached at CVHS at devassist@cvhsonline.org