Heartworm infections are very serious and potentially fatal for dogs. Heartworms are a type of roundworm known as filarids. They live in the arteries, lungs, and heart of an infected animal. Many mammals such as dogs, cats, foxes, and even people can contract heartworms.
Heartworm infestation is spread by infected mosquitoes. When an infected mosquito bites a dog it deposits heartworm larvae under the skin. The larvae eat through the skin and connective tissue for up to two months before reaching the bloodstream. Once in the blood, heartworms are transported to the arteries and lungs where they mature into adults. At six months of age, heartworms will begin producing offspring. Heartworms may live for up to seven years, with males reaching eight inches and female worms growing to twelve inches.
In reaction to the infestation, the organs' heartworms inhabit become inflamed. Because this inflammation interferes with blood flow, the most common cause of death from a heartworm infestation is blood clots in the lungs or congestive heart failure.
The only way for your dog to become infected with heartworms is through a mosquito bite. Dogs can not be infected by eating or coming into contact with dog waste that contains the eggs of heartworms. An infected dog cannot spread heartworms to another dog.
Heartworms are a dangerous parasite and can permanently damage a dog's health. Even once treated, the damage the worms cause may be permanent. Please -- if you have not done so already -- put your dog on a preventative medication.