Leptospirosis is a potentially fatal zoonotic disease dogs acquire from contaminated water and soil, with vaccination being the most effective welfare protection in endemic areas.
Leptospirosis causes acute kidney and liver failure with associated severe pain, weakness, and systemic illness. Dogs that survive significant organ damage face lifelong chronic kidney disease management. The vaccine is highly effective and safe, making leptospirosis largely a preventable disease in the domestic dog population. Geographic and lifestyle risk assessment should inform vaccination decisions - urban dogs in endemic areas, hunting dogs, and dogs with water body access have significant exposure risk that warrants annual vaccination.