Lyme disease

Lyme disease is a condition transmitted through a tick bite. A tick can infect both humans and dogs; in this article, we focus on infection in dogs.

A tick must have been attached to a dog’s body for at least 24 hours to infect the animal with the Borrelia burgdorferii bacteria, the cause of Lyme disease. The Borrelia burgdorferii bacteria travel through the bloodstream in the body, searching for a suitable place to settle; tissues, muscles, and organs are considered suitable by the bacteria.

Symptoms

Only 10% of all dogs infected with the Borrelia burgdorferii bacteria show symptoms. Because the symptoms are often vague and general, it is difficult to determine if a dog is suffering from Lyme disease. Symptoms associated with Lyme disease include:

• Recurring lameness due to inflamed joints
• Reduced appetite
• Fever
• Swollen glands around the tick bite
• Kidney damage
• Heart abnormalities
• Damage to the central nervous system
  
  

The characteristic red ring that appears around a tick bite in humans is rarely visible in dogs.

Diagnosis

Because the symptoms of Lyme disease are often very general, they can sometimes be attributed to another condition. As a result, the disease is often diagnosed at a later stage, usually when kidney failure occurs.

A veterinarian can diagnose a dog with Lyme disease based on symptoms, the owner’s observations, and blood tests. Blood tests should reveal whether a dog has produced antibodies against the Borrelia burgdorferii bacteria.

However, the blood test result can sometimes be false-positive; this means the bacteria are not currently present in the dog’s body, but the dog has produced antibodies against the bacteria (the dog was previously infected but successfully eliminated the bacteria). To rule out a false-positive result, a veterinarian can perform additional tests, such as a PCR test. A PCR test can detect whether DNA from the Borrelia burgdorferii bacteria is present in the dog’s tissues or bodily fluids.

Treatment

A veterinarian will usually prescribe a course of antibiotics for an infected dog. This antibiotic treatment lasts at least two to three weeks, sometimes longer. Generally, dogs respond well and quickly to antibiotic treatment. Because the joints often become inflamed with Lyme disease, a veterinarian may also prescribe anti-inflammatory drugs; however, this is not a treatment but symptom relief.

If you suspect your dog has Lyme disease, contact your veterinarian. The chance of lasting complaints is smaller when treatment is started early.

It is possible for a dog to remain a carrier of the Borrelia burgdorferii bacteria. When a dog’s immune system weakens, for example due to illness or old age, symptoms may reoccur.