Heartworm Disease

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Where do heartworms come from?
Heartworms are spread by mosquitoes. When a mosquito feeds on an animal, larval forms of heartworms are injected into the animal.

Can my pet catch heartworms from another heartworm positive animal?

Not directly. The life cycle of the heartworm parasite requires that it pass through the mosquito for development. The more positive dogs in an environment, though, the more potential for mosquitoes to be infective.

How serious is heartworm disease?

Heartworm disease is an extremely serious condition. The only way to determine the quantity of adult worms is by ultrasound or post-mortem examination. Therefore, any positive test should be taken seriously. Heartworms affect the heart’s ability to circulate blood. This in turn decreases the amount of blood to vital organs, such as the liver and the kidneys, as well as the heart itself. Any of these organs can subsequently become impaired, causing liver, kidney, or heart failure – any of which may be fatal.

My dog has Heartworms. What are my options?
Immiticide – This is an injectable mediation that kills the adult worms that live in the dog’s heart. A dog must stay overnight, as 2 injections are given 24 hours apart. After treatment, it is important to keep your dog indoors and quiet for 6 weeks.

Prior to treatment, bloodwork and xrays are done to determine the stage of the heartworm disease. This helps to identify any potential problems that might cause complications to your dog during the treatment. In some circumstances, the xrays and bloodwork can be declined by the owner. This is considered against medical advice, and the likelihood of complications cannot be assessed without these diagnostics.

Starting HW preventative on a dog known to have heartworms does not effect the adults that live in the heart. It does, however, prevent the dog from acquiring any more heartworms from the environment (mosquitoes). Your dog remains at risk for severe complications, including death, from the present heartworms. In addition, care must taken after starting HW prevention because this medication causes the baby heartworms in the bloodstream to die.

What are the risks of not treating the adult worms?
The adult worms that live in the heart are a constant source of danger. Their presence can cause localized infection and inflammation or impair blood flow resulting in organ failure. They can also break off and cause sudden death and/or a potentially fatal pneumonia. Any dog known to have heartworms should be kept quiet to decrease the likelihood of secondary problems.