Heartworm is a worm which lives in the heart and blood vessels of dogs and less commonly cats. Transmitted by mosquitoes, it has the potential to cause serious, chronic and fatal heart and lung disease in unprotected pets. Humans can occasionally be infected with heartworm with severe consequences.
Adult heartworms are about 20cm long and 1mm in diameter and live in the heart and blood vessels going to the lungs. They produce larval offspring called microfilaria that float around the blood stream. Mosquitoes suck blood containing microfilaria from infected animals and then transmit these larvae from animal to animal. After initial infection these larvae take approximately 6 months to develop into adult worms which reside in the pet’s heart.
Heartworm physically blocks the heart and lungs causing problems with the function of these organs. Clinical signs of heartworm disease are varied but may include coughing, sluggishness and difficulty breathing. Some infected animals may show no signs of the disease at all.
Heartworm infection is diagnosed by performing a simple blood test with results available within 10 minutes. As dead worms aren’t voided from the body the blood flow pushes the dead worms from the heart into the lungs causing lung disease. Animals that are infected with heartworm are treated slowly to minimise the effects of the dead worms on the health and survival of your pet. Treatment can be expensive and dangerous especially if there are many worms present.
The good news is heartworm is completely preventable. Many products are available to prevent heartworm disease.