Heartworm disease causes serious cardiovascular and respiratory damage in dogs. Prevention is safe and effective, making this one of the most preventable serious welfare problems in companion animals.
Heartworm disease causes progressive cardiovascular and respiratory suffering that significantly impairs quality of life before it is often diagnosed. The insidious onset means many dogs have substantial worm burdens and organ damage before clinical signs are apparent. Treatment of established disease, while effective, requires melarsomine injections and strict exercise restriction that are themselves welfare challenges, particularly for active dogs confined for weeks. The welfare case for consistent preventive medication is compelling as prevention is safe, inexpensive relative to treatment, and completely effective when administered correctly and consistently. Owner education about the importance of year-round prevention even in apparently low-risk environments is critical, as mosquito populations and heartworm range are expanding with climate change.