As mentioned last week, most pet owners know a litlte about heartworm, mostly that their vets test for it and that it's spread by mosquitoes.  But what is heartworm really?

Heartworm is just like it sounds-a worm that lives in the heart.  This is different, however, from intestinal parasites/worm which live in the intestinal tract.  Those worms are picked up from infected stool or soil.  Heartworm is spread by mosquitoes, so every dog in the US (including Alaska!) is at risk, even if they are long haired, double coated, or never ever go outside.  Cats are also at risk, even if they are indoor only.

Mosquitoes bite a dog (or cat) infected with Heartworm and pick up the baby heartworms (Microfilaria).  After 2 weeks, the microfilaria have gone to their larval stage.  The mosquito will then bite a healthy dog and spread the disease.  The larvae take 6 months in the bloodstream to mature into adult heartworms.  The adult heartworms live in the heart.

Heartworms can live for up to 7 years!  Symptoms of heartworm infection include lethargy, coughing, trouble breathing, exercise intolerance, vomiting, decreased appetite, and even death.  Cats often show no symptoms, and heartworm may not be caught until the cat has died.  There is no heartworm treatment for cats.  Dogs may be infected with heartworms and not show any signs for awhile, which is why it is important to test every year for heartworm.

Once your pet is tested for Heartworm disease, it is time to begin heartworm prevention.  The test your veterinarian will do is a blood test that looks for the adult heartworms.  The American Heartworm Society and the manufacturers of heartworm preventatives recommend testing anually for heartworm, even if the pet is on prevention year round.  Heartworm preventative works to kill any mircofilaria that enter the bloodstream, which is why it's extremely important to give your dog and cat heartworm prevention every month.  It is much cheaper and much easier on your pet to prevent heartworm disease than to attempt to treat it.

Benefits to year round heartworm prevention, besides keeping your pet from getting heartworm, is that most also include a dewormer for common parasites, and some also have a flea preventative.  At Suburban, when your pet is heartworm tested, we also test for two tick-borne diseases, Lyme & Erlichia.

Be sure to check out the American Heartworm Society for more information on Heartworm.  Your veterinarian will be happy to answer any questions on heartworm disease or preventatives.

http://www.heartwormsociety.org/pet-owner-resources/heartworm.html

http://www.heartwormsociety.org/pet-owner-resources/faqs.html