Heartworm disease causes significant suffering in dogs but is almost entirely preventable with widely available, affordable medication. Access barriers and owner education remain challenges.
Heartworm disease is a compelling example of a major animal welfare problem that is almost entirely preventable through accessible, affordable intervention. The suffering caused by established heartworm infection — exercise intolerance, breathing difficulties, progressive organ failure — is significant and prolonged. Yet the disease continues to impose enormous welfare costs on dog populations primarily because of access barriers to veterinary care and preventive medication. Low-income dog owners disproportionately bear this welfare burden. Community veterinary programs and subsidized prevention have demonstrably reduced heartworm prevalence in targeted populations. The combination of climate change expanding mosquito range and ongoing access disparities suggests that heartworm will continue to be a significant welfare challenge without systemic interventions.