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Resources > Healthcare Tips & Alerts > Heartworms

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Heartworms are known to occur throughout the U.S., and though they have been 100 percent preventable for decades, they are still common in dogs and cats.  Transmitted by mosquitoes, they are among the most damaging canine and feline parasites.  Heartworms are transmitted by feeding mosquitoes and, once mature, take residence in the heart and large vessels of the lungs.

Heartworms can be a very serious problem for both dogs and cats, especially those in mosquito-infested areas.  Because heartworms live in the bloodstream, lungs and heart, they can kill or seriously debilitate pets that are infected with them.

Your veterinarian can conduct a simply blood test to determine if your pet has heartworms or heartworm disease.  Diagnosis in cats can be more challenging.  feline heartworm disease can differ significantly from canine heartworm disease.  Cats with clinical heartworm disease usually show respiratory signs such as coughing and/or difficulty breathing, or even intermittent vomiting not associated with eating.  Other signs include weight loss and/or diarrhea without accompanying respiratory signs.  The respiratory signs are difficult to differentiate from those observed with feline asthma.

All dogs and cats are at risk, even those animals that primarily live indoors.  However, heartworms are preventable. A year-round preventive program is recommended by authorities and is most effective to keep pets free of heartworms.  Preventive treatment should begin at six or eight weeks of age in puppies and after tests have been conducted in older dogs to determine if your dog has already been infected.  If your dog does have heartworms, your veterinarian can advise you about treatment options.  In dogs over six months of age, a blood test is necessary before starting medication.