Dog Leptospirosis Signs: Symptoms, Treatment & Costs

Recognize illness in your dog

Leptospirosis can cause fever, reduced appetite, vomiting, muscle pain, changes in urination and yellowing of the eyes or gums in dogs. It can damage the kidneys and liver and can spread to people. [1] These signs do not confirm the cause. A dog with breathing difficulty, collapse or no urine needs emergency care rather than a home diagnosis.

What the signs may mean

Dogs become infected through contact with infected urine, contaminated water or soil, or infected animals. City, suburban and rural dogs can all be exposed. [1] A history of swimming or wildlife contact is useful to report, but its absence does not exclude leptospirosis.

Signs vary, and some infected animals show no apparent illness. Fever, lethargy, loss of appetite, muscle pain, vomiting, altered thirst or urination, and jaundice can occur. [1] Increased or decreased urine production can accompany kidney injury; hepatic dysfunction and pulmonary hemorrhage are also recognized manifestations. [2] Do not use the order in which signs appear to rule the disease in or out.

Record what your dog actually eats and drinks, changes in urine output, vomiting, visible bleeding and breathing effort. Tell the clinic about possible exposures, vaccination history and medications already given. Do not wait for jaundice or every listed sign before asking for help.

Diagnosis and treatment need an individual plan

Diagnosis combines the clinical picture with specific tests. ACVIM recommends combining antibody testing with tests that detect the organism, often PCR on blood and urine. Repeat antibody testing may be needed; one negative result does not exclude leptospirosis. Samples are ideally collected before antibiotics when feasible, but treatment should not be delayed while results are pending. [2]

Veterinary treatment may include antibiotics, carefully monitored fluid therapy and support for affected organs. Some dogs require dialysis. Early treatment can improve recovery, but organ damage may be permanent. [1] Fluids must be individualized to urine production, hydration and respiratory status; excessive fluid administration can be harmful. [2]

Follow the prescribed treatment and recheck plan. Contact the clinic about vomiting, missed medication or difficulty administering it rather than changing treatment yourself. Costs depend on testing, local fees, hospitalization, illness severity and the need for intensive care or referral.

Changes in urination or other kidney-related signs and blood in the urine can have other causes as well. These linked symptom guides do not establish whether leptospirosis is responsible.

Prevention and protecting the household

AAHA updated its canine guidance in 2024 to recommend leptospirosis vaccination as a core vaccine for all dogs. [3] Ask your veterinarian about the appropriate product and schedule. Vaccines reduce risk but do not cover every strain; vaccination remains recommended after natural infection. [1]

Reduce access to potentially contaminated water and control rodent exposure. Avoid urine or blood from an infected animal before proper treatment. If contact is unavoidable, cover wounds with a waterproof dressing and use protective clothing such as gloves and boots. Wash hands after handling contaminated material. Contact a healthcare professional about possible exposure. [1]

When to See a Vet

• Seek emergency care for difficulty breathing, collapse, marked weakness or unresponsiveness.
• Seek emergency care if your dog produces no urine, repeatedly strains without passing urine, or coughs or vomits blood.
• Contact a veterinarian urgently for yellow eyes or gums, repeated vomiting, or a major change in drinking or urination with illness.
• Contact your vet promptly for fever, muscle soreness, reduced eating or lethargy after possible exposure; do not wait for all signs to appear.

Frequently Asked Questions

Is leptospirosis contagious from dogs to humans?

Yes. Infection can spread through infected urine or contaminated water or soil. Avoid contact with urine or blood before proper treatment, cover wounds, use protective clothing when contact is unavoidable, and wash your hands. Contact a healthcare professional if you may have been exposed. [1]

How much does leptospirosis treatment cost for a dog?

Costs depend on local fees, illness severity, hospitalization, testing and whether intensive care or dialysis is needed. Ask the treating team for an estimate and discuss referral options. A fixed price cannot describe every dog’s care.

Should my dog be vaccinated against leptospirosis?

AAHA recommends leptospirosis vaccination as a core vaccine for all dogs following its 2024 guideline update. [3] Vaccines reduce risk but do not cover every strain. [1] Ask your veterinarian which product and schedule are appropriate rather than assuming an urban or indoor lifestyle removes the need for vaccination.

Can leptospirosis cause permanent kidney damage?

Yes. Kidney or other organ damage caused by leptospirosis can be permanent. [1] Follow-up testing helps the veterinarian assess recovery and decide what ongoing care is needed. Improving appetite or energy does not replace the planned reassessment.

What water sources increase leptospirosis exposure?

Contaminated standing or slow-moving water, including puddles, ponds, rivers and streams, can expose dogs to infected animal urine. Contaminated soil and direct animal contact also matter. Dogs in cities, suburbs and rural areas can be infected. [1]

References

1. Centers for Disease Control and Prevention. Leptospirosis in Animals. https://www.cdc.gov/leptospirosis/pets/index.html
2. Sykes et al. Updated ACVIM consensus statement on leptospirosis in dogs. Journal of Veterinary Internal Medicine. https://onlinelibrary.wiley.com/doi/10.1111/jvim.16903
3. American Animal Hospital Association. Canine Vaccination Guidelines Resource Center: 2024 leptospirosis update. https://www.aaha.org/resources/2022-aaha-canine-vaccination-guidelines/resource-center/