Heartworm disease is a serious, often fatal condition in dogs that can result in severe lung disease, heart failure, organ damage and more. Preventing heartworm disease is both easier on your pet, and on your wallet, than treating the disease after your dog gets ill. Our Somerset vets explain why.
What is heartworm disease?
Heartworm disease is primarily caused by a parasitic worm called dirofilaria immitis.
Your dog is a natural host for this parasite, meaning that while living inside your pet, the worms mature into adults and then mate and produce offspring. This serious condition is called heartworm disease because these foot-long worms make their home in the heart, lungs and blood vessels of an infected dog, causing severe lung disease, heart failure and damage to other organs in the body.
Signs of Heartworm in Dogs
Sadly, in dogs, the signs of heartworm disease don’t typically appear until the disease has progressed to more advanced stages, with possibly several hundred worms in the dog at that point. Once symptoms do become evident they include fatigue, swollen abdomen, coughing, difficulty breathing and weight loss.
How is heartworm transmitted?
Mosquitoes are an essential part of the heartworm lifecycle. When a mosquito drinks the blood of an infected animal, it sucks up microscopic baby worms. Over the next ten to 14 days these baby worms mature and become “infective stage” larvae. Then, when the mosquito takes a bite out of a healthy animal, it deposits these larvae. Once inside a new host, it takes about six months for the larvae to mature into adult heartworms. Once mature, heartworms can live for five to seven years in dogs.
When should my dog be tested for heartworms?
Heartworm testing is part of your annual routine examination for your dog. Annual testing is necessary to ensure that the prevention program is working. Heartworm medications are highly effective, but dogs can still become infected. If you miss just one dose of a monthly medication, or give it late, it can leave your dog unprotected.
Diagnosing Heartworm
Blood tests can be done at your vet's office to detect heartworm proteins, called antigens, which are released into the animal's bloodstream. These antigens first become detectible between 5-7 months after your pooch has been infected.
Treatment for Heartworm Disease in Dogs
The reason that vaccinations and prevention are so important when it comes to heartworm is that the treatment for the disease can cause serious health complications and be toxic to your pup's body. Not only that, treatment is can be expensive because it requires multiple visits to the vet, bloodwork, x-rays, hospitalization, and a series of injections.
If your dog is diagnosed with heartworms, your vet can use melarsomine dihydrochloride (which is an arsenic-containing drug that kills adult heartworms) to treat your pet. Melarsomine dihydrochloride is administered by an injection into the back muscles of the dog in order to kill the parasites.
Topical FDA approved solutions are also available to treat heartworm disease. These solutions can help to get rid of parasites in the bloodstream when applied directly to the animal's skin.
How likely is my pet to contract heartworms?
The truth is, heartworm disease has been diagnosed in all 50 states, and risk factors are impossible to predict. Multiple variables, from climate variations to the presence of wildlife carriers, cause rates of infections to vary dramatically from year to year—even within communities.
Because infected mosquitoes can come inside, both outdoor and indoor pets are at risk. This is why prevention is the best option.
Heartworm Prevention
Keeping your dog up-to-date on their vaccinations and on preventative medication is the best way to prevent heartworm disease from impacting your dog's health. Even if your pooch is already on preventive heartworm medication, it is recommended that dogs be tested for heartworms annually. Puppies under seven months of age can be started on heartworm prevention without a heartworm test.
Heartworm prevention is safer, easier and much more affordable than treating the progressed disease! A number of heartworm preventive medications can also help protect against other parasites such as hookworms, whipworms and roundworms.