Heartworm Prevention by Frank Utchen, DVM

A Monhly Pill for Your Canine Could Prevent Heartache

Recently there was a report of a little dog named Callie. She was one of the hundreds of pets saved in the aftermath of Hurricane Katrina, a sweet-natured mixed breed whose foster family fell for her so hard they were ready to offer her a permanent home. That never happened, because Callie died. 

What killed her wasn't anything related to the hurricane. She didn't die in an accident. She was needlessly killed by a disease that's easily prevented. She died because the people who once owned her didn't give her a monthly heartworm preventative tablet.  Callie died weeks after the hurricane, from complications of treatment for heartworm disease. A single dose of a chewable medication every month would have prevented her death by keeping her free of the parasites. 

Dogs become infested with heartworm when bitten by a mosquito carrying microscopic, immature heartworm larvae picked up from another dog.  Once injected by a mosquito, the larvae take several months to migrate through the body and develop into adult heartworms — up to 14 inches long — that can fill the heart and block blood flow to the lungs.  Early signs of the disease involve a drop in energy and an unproductive cough. If left untreated, the worms can cause organ damage elsewhere in the body, and eventually can lead to heart failure and death.  A pet with heartworms can be treated, but the cure is difficult, expensive and sometimes fatal.

This is one case where prevention is much, much better than the cure, which is why heartworm prevention is so important. The American Heartworm Society estimates that 27 million dogs are not on preventive medicine, leaving them at risk for this deadly disease, which is present in all states except Alaska.  The disease is most prevalent in the Midwest and Gulf Coast states, but Callie will not be the only such casualty. Rescue groups estimate that some 80 percent of dogs taken from the disaster zone are infested with heartworms. 

At our practice in San Ramon we have treated four heartworm infected dogs from New Orleans in the last six months, and have seen other dogs infected locally.  Fortunately, all of those dogs have lived (and one, Molly, was recently returned to Louisiana and reunited with her owners!).  There is no legal requirement that dogs be given heartworm preventative medication as there is for triennial rabies immunization.

Rabies immunization laws are intended to protect the health of the human population although the incidence of rabies in dogs in the United States is extremely low.  However, the prevalence of heartworm disease among the canine population vastly exceeds that of rabies, and for our canine companions, prevention of this disease should be considered equally important. 

Heartworm preventative medication generally costs no more than a few dollars a month. The monthly medication also prevents major intestinal parasites; protecting your dog's digestive health as well as his heart. The intestinal parasites prevented by this medication are actually contagious to humans, so prevention by this single medication will benefit you as well as your dog.  Despite the importance and ease of preventing these parasites it is estimated that most dogs do not receive their heartworm preventative tablet every month. 

Which brings me back to little Callie.  If, like Callie, your dog isn't on heartworm preventive, my hope is to raise your awareness of this deadly-yet easily prevented-disease.  Have your dog checked by your veterinarian to make sure he or she isn't already carrying this infection, and if they're not, put your dog on heartworm preventive.  Callie died on the verge of a new life with people who truly cared about her. If you love your dog, protect him or her. It's a really small price to pay for the companionship of a pet.  

(c) 2006 The Oakland Tribune. All rights reserved. Reproduced with the permission of Media NewsGroup, Inc. by NewsBank, Inc