Leptospirosis in Dogs: Symptoms, Transmission, and Vaccination

What is leptospirosis in dogs?

Leptospirosis is an infectious disease caused by bacteria of the genus Leptospira. It can be life-threatening in dogs and is transmissible to humans (zoonosis). Transmission occurs primarily through the urine of infected animals—particularly rats, mice, livestock, and wild animals—as well as through contaminated water and soil.

In Germany, leptospirosis is a relatively common disease among dogs that spend time in bodies of water, meadows, or wooded areas. The disease primarily affects the kidneys and liver, but it can damage multiple organ systems simultaneously.

Background + Scientific Context

Schuller et al. (2015, Journal of Small Animal Practice, PubMed 25754172) published the European consensus on leptospirosis in dogs and cats: The consensus describes regional serovar variation (dominant serovars in Central Europe: Icterohaemorrhagiae, Canicola, Grippotyphosa, Bratislava) and recommends quadrivalent vaccines (L4) as the current standard—since older bivalent vaccines (L2) do not cover the serovars most common in Europe. Annual boosters are warranted for at-risk dogs (exposure to water, forested areas).

Sykes et al. (2011, Journal of Veterinary Internal Medicine, PubMed 21281351) summarized the ACVIM guidelines on leptospirosis: Acute leptospirosis often presents as peracute hepatic-renal failure with vomiting, jaundice, and hematuria. Serological diagnosis via MAT (Microscopic Agglutination Test) or PCR from urine/blood. Treatment: penicillin derivatives (acute phase) or doxycycline (elimination phase/carrier status).

André-Fontaine (2006, Veterinary Microbiology, PubMed 16765539) analyzed the incidence of canine leptospirosis in Europe: Climate change (milder winters, frequent flooding) promotes the spread of leptospires in the environment. Prevalence is increasing—urban dogs are exposed through contact with rats, standing puddles, and contaminated park areas.

Vitomalia-Position

Leptospirosis is a vaccine-preventable disease with the potential for serious complications—vaccination is one of the non-negotiable core recommendations for every dog that comes into contact with the outdoors. Owners whose dogs swim in bodies of water, explore areas with wildlife, or spend time on agricultural land should ensure their dogs receive the quadrivalent vaccine (L4) and seek immediate veterinary care at the first sign of acute illness.

When does leptospirosis become a concern?

• Dogs with access to bodies of water (ponds, rivers, puddles)
• Dogs in wooded areas or fields where they come into contact with wildlife
• Symptoms such as sudden vomiting, jaundice, bloody urine, and lethargy
• Vaccination Planning (L2 vs. L4)
• Zoonotic aspect: infected dogs can shed leptospires

Practical application

Clinical Presentation — Overview:

Vaccination: - L2 vaccine: covers the serovars Icterohaemorrhagiae and Canicola - L4 vaccine: also covers Grippotyphosa and Bratislava — the currently recommended standard in Germany - Primary vaccination series: 2 doses administered 4 weeks apart - Booster: annually (WSAVA recommendation for leptospirosis — unlike other core vaccines)

Diagnostics: - PCR from blood (acute phase) or urine (carrier phase) - MAT serology: Detection of antibodies against specific serovars

Common Mistakes & Myths

• “My dog never goes near water—he doesn’t need a leptospirosis vaccine.” Leptospires can survive even in puddles on forest trails, damp meadows, and in rainwater. Contact with water in the sense of a swimming pool isn’t necessary—damp ground is enough.
• “The old two-valent vaccine (L2) is sufficient.” In Germany, Grippotyphosa and Bratislava are common causes of clinical leptospirosis—which L2 does not cover. The European consensus recommends L4 as the standard.
• “Leptospirosis is not just a risk in rural areas.” Urban dogs are equally at risk from contact with rats, contaminated park areas, and puddles. Urban green spaces are not risk-free.

Current State of Research (2026)

Leptospirosis is a growing threat to dogs in Central Europe—exacerbated by climate change and increasing flooding. L4 vaccines (Nobivac L4, Versican L4) are considered the clinical standard. Recent research is investigating biomarkers for early kidney involvement and leptospirosis carrier status. The zoonotic aspect of the disease requires consistent education in both veterinary and human medicine.

Frequently Asked Questions

What are the symptoms of leptospirosis in dogs?

Typical symptoms include sudden vomiting, lethargy, yellowing of the eyes and mucous membranes (jaundice), bloody or brownish urine, thirst, and increased water intake (signs of kidney disease). The condition often progresses rapidly within a few days. If these symptoms occur together, it is imperative to seek immediate veterinary care.

Which vaccine protects against leptospirosis—L2 or L4?

L4 vaccines (quadrivalent) are the recommended standard in Germany, as they cover the most common serovars: Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. L2 vaccines (bivalent) do not provide protection against Grippotyphosa and Bratislava. Annual boosters are necessary—unlike with some other vaccines.

Can I catch leptospirosis from my dog?

Yes — Leptospirosis is a zoonotic disease. Infected dogs can shed leptospires in their urine. Mucous membranes or open wounds exposed to urine are potential entry points for humans. Hygiene measures are important when handling sick dogs; this is a notifiable disease in humans.

Related terms

• Vaccinations for Dogs
• Kidney Failure in Dogs
• Infectious Diseases in Dogs
• Tick Prevention for Dogs
• Leishmaniasis in Dogs

Sources & Further Reading

1. Schuller, S., Francey, T., Hartmann, K., Hugonnard, M., Kohn, B., Nally, J. E., & Sykes, J. (2015). European consensus statement on leptospirosis in dogs and cats. Journal of Small Animal Practice, 56(3), 159–179. https://pubmed.ncbi.nlm.nih.gov/25754172/

2. Sykes, J. E., Hartmann, K., Lunn, K. F., Moore, G. E., Stoddard, R. A., & Goldstein, R. E. (2011). 2010 ACVIM small animal consensus statement on leptospirosis: Diagnosis, epidemiology, treatment, and prevention. Journal of Veterinary Internal Medicine, 25(1), 1–13. https://pubmed.ncbi.nlm.nih.gov/21281351/

3. André-Fontaine, G. (2006). Canine leptospirosis — do we have a problem? Veterinary Microbiology, 117(1), 19–24. https://pubmed.ncbi.nlm.nih.gov/16765539/