Gardner Pet Series

Dogs and the Pesky Mosquito!
Summer is upon us and it is mosquito season.  “So what”, you say.  “Why should I care? …..So, I should care because my dog doesn’t want to get heartworms.  What is that all about?” Many people who come into our clinic on a daily basis really do not understand much about this parasite—the heartworm. Many people think if they can’t see it, their pet must not have it.
Heartworms are transmitted by mosquitoes from one dog to another.  They are a parasite, which means that they live and feed off of another living being, in this case, your dog. When the mosquito takes a blood meal from an infected dog they suck up the tiny microscopic heartworm larvae (microfilariae), which are swimming around in the bloodstream of the dog.  These larvae then molt in the mosquito’s body and migrate to the salivary glands of the mosquito. In order for a mosquito to take a blood meal from your dog, they inject their saliva into your dog.  In doing so, they also inject the mature microfilariae of the heartworm into your dog. Over the course of the next 6-7 months these microscopic larvae will migrate to the heart and lung vessels of your dog and mature into adult heartworms.  Adult heartworms are about 10-12 inches long and about the size around of spaghetti.  As adults, they live in the heart and pulmonary arteries of the dog (canine family), their primary host. The long term effects of heartworm infestation are severe lung disease and interference with circulation, resulting in liver failure and ultimately heart failure. Symptoms include shortness of breath, labored breathing, weight loss, coughing, and fluid buildup in the abdomen.
“Can it be treated?” you ask.  Yes, when diagnosed early, heartworm disease can be treated.  However, the treatment is expensive and, presently, the drug used to treat the disease is not readily available from the manufacturer in the U.S.  The active ingredient cannot be purchased by the sole manufacturer, at the present time in the U. S. The manufacturer has requested special permission from the FDA to purchase the ingredient from a source in Europe.
However, as your veterinarian, we must make an application on behalf of your pet to purchase the drug and there is no guarantee that we will be able to purchase it to treat your dog.
So, where does that leave you, as a pet owner, in protecting your dog from heartworm disease?   There are several very effective heartworm prevention drugs on the market and available from your veterinarian to prevent this ugly disease.  In addition, they are very inexpensive.  They come in different forms—a monthly tablet, a topical spot treatment and an injection that is given every six months. Most veterinarians recommend giving the preventative all year round.  You can prevent the disease for 7-8 years for the same cost as treating the disease one time, based on the cost of the treatment when the treatment drug was available.  The present cost of the treatment, should your dog get heartworms, may be much more considering the limited availability of the treatment drug.
“How do I get my dog started on this heartworm preventative medication?” you ask.   If you have a puppy less than six months of age, you can take it in the see your veterinarian and he/she can prescribe the preventative medication for your dog.  If your dog is over six months of age, your veterinarian will take some blood and run a test to insure that your dog does not presently have adult heartworms, and then prescribe the preventative for your dog.
Eileen Mertz, DVM
All opinions are that of the contributor and based on their sole professional experience and not that of the Gardner News.