Lyme Disease in Dogs: Symptoms, Diagnosis, and Treatment

What is Lyme disease in dogs?

Lyme disease is an infectious disease caused by the spirochete bacterium Borrelia burgdorferi sensu lato, which is transmitted through the bite of infected ticks (Ixodes spp.). In Europe, I. ricinus (the common wood tick) is the primary vector.

Key point: Most infected dogs show no symptoms at all or only mild ones. Only a small proportion develop clinical disease—and often not until weeks or months after the tick bite. This makes diagnosing Lyme disease challenging.

Background + Scientific Context

Littman et al. (2018, Journal of Veterinary Internal Medicine, PubMed 29484732) updated the ACVIM consensus on Lyme disease in dogs and cats: The most common clinical signs are acute, migratory lameness (often unilateral), fever, lymphadenopathy, and lethargy. Borrelia-associated nephropathy (Lyme nephritis) is rare but has a poor prognosis—it occurs primarily in Labrador Retrievers and Golden Retrievers and leads to kidney failure if left untreated.

Krupka and Straubinger (2010, Veterinary Clinics of North America, PubMed 20610020) described the pathogenesis, diagnosis, and treatment: Serological tests (ELISA, Western blot) form the basis of the diagnosis—however, antibodies against B. burgdorferi can also be detected in clinically unremarkable, vaccinated, or previously infected dogs. Titers alone do not indicate active disease. The Quantum-C6 test and clinical symptoms must be consistent.

Straubinger (2000, Journal of Clinical Microbiology, PubMed 10747134) quantified B. burgdorferi DNA in canine tissues more than 500 days after infection using PCR: The organisms persist in joints and other tissues despite antibiotic treatment—complete eradication is difficult. This explains why relapses and chronic courses occur, even after successful treatment.

Vitomalia-Position

There is no need to panic about Lyme disease after every tick bite. Most dogs that are bitten do not develop clinical disease. Rather than overreacting, it makes more sense to use consistent tick prevention (antiparasitic medications), get vaccinated in high-risk areas, and monitor your dog closely after tick bites. If lameness, fever, or lethargy occur after tick season: seek veterinary evaluation with serological testing.

We oppose the use of antibiotics for preventive purposes without a confirmed diagnosis—antibiotic resistance is also a growing problem in veterinary medicine.

When does Lyme disease become a concern in dogs?

• In cases of sudden lameness (intermittent, migratory) following tick season
• In cases of fever of unknown origin combined with swollen lymph nodes
• For dogs in endemic areas: Southern Germany, the Black Forest, the Alpine foothills, the Netherlands, and Scandinavia
• As part of the differential diagnosis for kidney disease: Lyme nephritis in retrievers
• For dogs without current tick protection

Practical application

Diagnosis of Lyme disease in dogs:

Treatment: Doxycycline (10 mg/kg/day for 4 weeks) is the drug of choice. Clinical symptoms usually improve within 24–48 hours—if there is no improvement, this suggests that Lyme disease is not the sole cause. Check blood counts and kidney function before and after treatment.

Vaccination: Borrelia vaccines for dogs are available in Germany (recombinant OspA vaccines). Recommended in high-risk areas or for dogs that spend a lot of time outdoors—however, vaccination is no substitute for tick prevention.

Common Mistakes & Myths

• “Tick bite = Lyme disease.” Not every tick is infected, and not every infection leads to illness. In Central Europe, approximately 15–30% of ticks carry B. burgdorferi —but the likelihood of transmission only increases after the tick has been feeding for 24–48 hours.
• “A positive Borrelia titer indicates active disease.” Antibodies may result from a previous infection, vaccination, or subclinical exposure. Titers must always be evaluated in the context of clinical symptoms.
• “After a course of antibiotics, the dog is cured.” Straubinger (2000) shows that B. burgdorferi persists in tissues. Clinical cure and complete microbiological eradication are not the same thing.

Current State of Research (2026)

New OspC-based vaccines with broader serovar coverage are currently in development. The C6 antibody test is becoming increasingly important in diagnostics—it distinguishes between vaccine-induced antibodies and infection-induced antibodies. Genetic studies are being conducted to investigate the predisposition to Lyme nephritis in certain dog breeds.

Frequently Asked Questions

How can you tell if a dog has Lyme disease?

Typical signs: sudden, intermittent lameness (affecting different limbs), fever, lethargy, swollen lymph nodes. Symptoms appear weeks to months after a tick bite. Many dogs remain completely asymptomatic. If borreliosis is suspected, consult a veterinarian for serological testing.

Is it always necessary to treat Lyme disease in dogs?

Only dogs showing clinical signs of illness are treated—not merely on the basis of a positive test result in the absence of symptoms. In cases of active disease (lameness, fever), doxycycline administered over 4 weeks is the standard treatment. For Lyme nephritis: more intensive therapy, with the prognosis depending on the kidney findings.

Can Lyme disease in dogs be prevented?

Yes: consistent tick prevention (spot-on treatments, tick collars, oral medications) reduces the risk of transmission. In endemic areas, vaccination is recommended. Checking for ticks daily and removing them within 24 hours significantly reduces the risk of infection.

Related terms

• Ticks on Dogs
• Anaplasmosis in Dogs
• Antiparasitic medications for dogs
• Complete blood count in dogs
• Kidney Disease in Dogs
• Tick-borne encephalitis in dogs

Sources & Further Reading

1. Littman, M. P., Gerber, B., Goldstein, R. E., Labato, M. A., Lappin, M. R., & Moore, G. E. (2018). ACVIM consensus update on Lyme borreliosis in dogs and cats. Journal of Veterinary Internal Medicine, 32(3), 887–903. https://pubmed.ncbi.nlm.nih.gov/29484732/

2. Krupka, I., & Straubinger, R. K. (2010). Lyme borreliosis in dogs and cats: background, diagnosis, treatment and prevention of infections with Borrelia burgdorferi sensu stricto. Veterinary Clinics of North America: Small Animal Practice, 40(6), 1103–1119. https://pubmed.ncbi.nlm.nih.gov/20610020/

3. Straubinger, R. K. (2000). PCR-based quantification of Borrelia burgdorferi organisms in canine tissues over a 500-day postinfection period. Journal of Clinical Microbiology, 38(6), 2191–2199. https://pubmed.ncbi.nlm.nih.gov/10747134/