Leptospirosis is a bacterial disease affecting dogs with increasing urban prevalence, causing severe organ damage and significant welfare harm that is largely preventable through vaccination and awareness.
Leptospirosis causes severe and rapid deterioration in affected dogs, with organ failure progression that can be fatal within days without intensive treatment. The welfare impact of acute leptospirosis includes extreme pain, respiratory distress, and multi-organ dysfunction. Prevention is far preferable to treatment, both for animal welfare and for owner finances, as intensive supportive care is expensive. Vaccination is effective and should be part of the core protocol for dogs with outdoor access, particularly those that swim in natural water bodies, visit dog parks, or live in areas with known wildlife activity. After flooding events, leash walking dogs away from standing water dramatically reduces exposure risk.