06/19/2026
Heartworm disease is caused by the parasite Dirofilaria immitis, transmitted through mosquito bites, and primarily affects the heart, lungs, and blood vessels. Symptoms often develop gradually and may be subtle in the early stages, making early detection challenging.
Persistent Coughing: A dry, soft cough that may worsen after exercise or even at rest is often one of the first signs.
Fatigue and Reduced Activity: Dogs may tire easily during walks or play, showing lethargy or decreased exercise tolerance.
Difficulty Breathing: Labored breathing, rapid panting, or shortness of breath can occur as heartworms strain the lungs and heart.
Weight Loss and Loss of Appetite: Gradual weight loss and reduced appetite are common, even in mild cases .
Fainting or Collapsing: Syncope may occur in advanced stages, often triggered by physical activity, due to restricted blood flow and oxygen delivery