Dog Heartworm Disease: Prevention and Treatment

Heartworm disease is a serious preventable parasitic infection causing severe cardiovascular damage in dogs with long treatment protocols.

Key Facts

Heartworm disease is caused by Dirofilaria immitis transmitted by mosquitoes throughout endemic areas
Adult worms live in the pulmonary arteries and right heart, causing inflammation and obstruction
Clinical signs progress from cough and exercise intolerance to right-sided heart failure
Treatment with melarsomine requires strict exercise restriction for 2-3 months during worm die-off
Dead worms can cause fatal pulmonary embolism if exercise is not strictly restricted during treatment
Monthly preventatives are highly effective and far safer than treating established infection
Climate change is expanding heartworm's geographic range as mosquito habitat expands

Welfare Considerations

Advanced heartworm disease causes severe exercise intolerance, coughing, and eventually right-sided heart failure with fluid accumulation. The treatment protocol is itself a welfare challenge - dogs must be confined for months during worm die-off to prevent fatal pulmonary embolism. Prevention is dramatically safer and more welfare-friendly than treatment. The months of strict restriction during treatment cause psychological stress alongside physical recovery.

What You Can Do

Administer veterinarian-prescribed monthly heartworm preventative year-round in endemic areas
Test dogs annually for heartworm infection even if on prevention - early detection improves outcomes
Follow exercise restriction protocols strictly during heartworm treatment - exceptions risk fatal embolism
Begin heartworm prevention in puppies at the earliest recommended age before exposure begins
Test and treat rescue dogs from endemic areas before placing them in heartworm-free regions
Spread awareness that heartworm is preventable - many dogs suffer unnecessarily from lack of prevention