Heartworm is a preventable parasitic disease causing severe cardiovascular damage in dogs. Understanding transmission and prevention protects dog welfare globally.
Heartworm disease causes progressive and severe suffering in affected dogs. The long prepatent period means dogs may be heavily infected before showing obvious signs, by which time significant cardiac and pulmonary damage has occurred. Treatment is prolonged, expensive and carries risks including pulmonary embolism from dying worms. The welfare case for prevention is overwhelming — monthly preventive medications are safe, affordable and highly effective. Welfare-conscious ownership includes regular heartworm testing and year-round prevention in areas where transmission occurs. Expanding geographic range due to climate change means more dogs are now at risk than historically.