Canine Leptospirosis: Vaccination and Welfare Protection

Leptospirosis is a serious bacterial zoonosis in dogs that causes potentially fatal kidney and liver disease, preventable through vaccination and exposure risk management.

Key Facts

Leptospirosis is caused by Leptospira bacteria shed in urine of infected wildlife (rats, raccoons, deer) into water and soil.
Dogs contract it through contact with contaminated water, soil, or infected animal urine.
Clinical signs range from mild fever to severe kidney failure, liver disease, pulmonary haemorrhage, and death.
Leptospirosis is a zoonosis — infected dogs can transmit the disease to humans.
The disease is more prevalent in warm, wet climates and in dogs with outdoor or water access.
Modern quadrivalent vaccines protect against four Leptospira serovars and significantly reduce disease risk.
Annual vaccination is recommended in endemic areas and for at-risk dogs.
Treatment requires aggressive hospitalisation with IV fluids and antibiotics — costs can be substantial.

Welfare Considerations

Leptospirosis causes acute, severe illness. Dogs with the pulmonary haemorrhagic syndrome — a rare but increasingly reported manifestation — experience respiratory failure that is rapidly fatal and profoundly distressing. Acute kidney injury causes the pain and nausea of uraemia; liver involvement causes jaundice and coagulopathy. The zoonotic dimension adds urgency — owners of infected dogs are at risk, particularly if they handle urine during illness or home care. The disease is largely preventable through vaccination, but vaccine hesitancy and cost barriers mean many at-risk dogs remain unprotected. Educating owners about leptospirosis risk, particularly for dogs swimming in natural water bodies, is an important preventive welfare intervention.

What You Can Do

Vaccinate dogs against leptospirosis annually, especially if they have access to natural water, wildlife, or rural environments.
Keep dogs away from stagnant water, flooded areas, and locations frequented by wildlife.
Seek veterinary care immediately if your dog develops fever, lethargy, vomiting, or decreased urination after water exposure.
Wear gloves when handling urine or body fluids from a dog suspected of leptospirosis.
Inform your vet of recent water exposure history to support rapid diagnosis.
Support rodent control around homes and farms to reduce environmental Leptospira contamination.