Heartworm Facts

  • Heartworms are transmitted by mosquitoes.
  • Adult Heartworms live in the right side of the heart.
  • They are 6-14 inches long. Several hundred may be present in the dog.
  • Heartworms impair blood circulation, resulting in damage to the heart, lungs, liver, and kidneys. Serious damage may occur, even before outward clinical signs are detected by the owner.
  • Advanced signs include difficulty breathing, coughing, tiring easily, listlessness, weight loss, fainting and death.
  • Heartworms are found throughout the United States and Canada.

Mosquitoes spread heartworms:

After ingesting blood from an infected dog, the microfilaria (juvenile heartworms) are transmitted to another dog or cat when the mosquito bites it. Once the heartworms mature, they begin reproducing additional microfilaria. It takes 3 to 6 months for adult heartworms to develop in a dog after an infected mosquito bites it. Heartworms occur in all breeds of dogs: large and small, shorthaired and longhaired, inside-dogs and outside-dogs. Heartworms also infect cats. A special test to detect heartworm disease is required annually. Treatment is very successful when the disease is detected early. The adult worms are killed with an injectable drug given in a series of 3 injections. A few days later, the worms begin to die, and are carried by way of the bloodstream to the lungs. They slowly decompose and are absorbed by the body over a period of several months. Topical, monthly oral or semi-annual injectable heartworm preventative is intiated at the same time.

Heartworms are Preventable:

Heartworm preventative is required year-round to prevent infestation. Routine testing for Heartworms once each year is required for all dogs. For your convenience, a 6 month injectable heartworm prevention, Proheart 6, is available, in addition to monthly chewable and topical hearworm preventatives.

Should you have any questions regarding your pet please call us at 210-496-1315.

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