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Heartworm in Dogs

Heartworm in Dogs

Heartworm in Dogs Facts

Heartworm disease can occur anywhere in the world, and it affects dogs, cats, and even other pets. A bite from a mosquito carrying the parasite causes heartworm in dogs. There are more than 70 different types of mosquitos that can carry heartworm disease.

At first, your dog may not display any symptoms of this dangerous illness. Heartworms can live 5-7 years inside your pet, and they can grow to be as longer than 8 feet in length.  After an infected mosquito bites your dog, it can take about eight months for the heart-worm parasite to show up. There are multiple ways to treat heartworms in dogs.  In addition, there is a possible heartworm cure.

It is important to note that animals cannot pass heartworms to each other. The only way to contract it is through mosquito bites. If the heartworms go undetected, they can have a devastating effect on your pet. The parasites can invade your dog’s heart and lungs, cause blockages and fluid build up. They can affect the animal’s energy level and eating habits. Left untreated, heartworms can be killers and cause permanent damage.

How to Avoid Heartworm in Dogs

The best way to avoid heartworm in dogs is to use prevention as recommended by your vet. He will usually prescribe pills that can protect your pet from heartworms, as well as other parasites and illnesses. Originally, the vets’ recommendation was to administer the heartworm preventative medication during the warm months of the year. Research has determined, however, that heartworm disease can occur any time mosquitos are present.

This means you should protect your pets year round. The American Heartworm Association estimates that more than 50% of dogs in the United States currently take heartworm preventative medicine. Owners lament the cost of monthly prevention but the cost to treat a heartworm positive animal is much higher.

There are other products, besides pills, that your vet can offer for the prevention of heartworms. There are topical heartworm medicines that are applicable on a monthly basis; or even injectables that can last up to six months. Depending on the size of your dog, heartworm preventative medication is usually $35 to $80 per year.

Heartworm disease infects more than one million dogs each year, in the United States. Only about one-third of these animals receive a diagnosis from a veterinarian. This disease is prevalent in all 50 states, but it is most common in humid and hot places. It is critical to protect your dog from heartworms disease and to understand the complications involved with it.

How Does Heartworm in Dogs Develop?

The life cycle of the heartworm in dogs begins when an animal receives a bite from a mosquito carrying the heartworm parasite. As worms develop and grow, the number of larva inside the host increases. These tiny organisms, known as microfilaria, are baby worms. Researchers can see these small beings in a blood sample. The larva will mature in about six months, to adult heartworms.

As these worms increase, they begin to affect more of your pet’s organs and body functions. The longer these parasites go undetected, the more damage can be done to the dog. Animals have been known to have more than 250 worms in their body. Symptoms of heartworm disease in dogs range from lethargy to loss of appetite.

Dogs with heartworms often become winded after very little exercise. They can have “fainting” spells after exertion. Hear worms in dogs can also cause extended stomachs or chests, as the parasites invade their heart and lungs. A persistent, dry cough is another symptom of heartworms. If you notice any of these signs, you should get your dog to the vet immediately.

Diagnosing Heartworms in Dogs

Your veterinarian will perform blood work tests to positively diagnose heartworms in your dog. He will also use x-rays and other tests to determine how severe the illness is in the dog. The treatment for heartworms is a drug called Immiticide.  As the name suggests, it does contain arsenic to kill the worms. Immiticide is an injection that kills the heartworm parasites.  It may take up to three doses of Immiticide to complete the heartworm treatment.

The entire process, to treat heartworms, can be as much as $1,000. This type of therapy is safer than methods in the past where vets used everyday arsenic and many more dogs died.

It is important to remember that while dogs can’t give this disease to each other, it is possible for your dog to get heartworms again, even if he has already had it. That is why prevention is crucial to the health of your dog. Year round heartworm protection will ensure that your dog is healthy and happy.


(The image above is a derivative of lloydcrew,; CC BY-SA.)

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