Lyme Tick Disease Symptoms in Dogs

Lyme tick disease in dogs is a serious illness that occurs most often in the northeastern United States, though it can occur throughout all 50 states. Lyme disease effects humans as well as animals and is spread by the common deer tick. Here's what you should know about the symptoms, transmission, diagnosis and treatment of Lyme disease in dogs.

How Lyme Disease Spreads

Lyme disease is spread by the bite of the common deer tick, which lives all over the continental United States. However, these ticks are most common in the northeastern United States, or the region stretching from Maine to Virginia. Lyme disease occurs most often in this region, but it can occur throughout the United States.

Lyme disease is caused by a spirochete bacteria known as Borrelia burgdorferi. Deer ticks are a common carrier for B. burgodorferi. Deer ticks become infected with B. burgodorferi when, as larvae, they feed on small animals like mice. Later, the adult deer tick feeds on larger animals, like dogs, which then become infected with Lyme disease.

In order for your dog to contract Lyme disease, the infected tick must feed from him for a period of at least 48 hours. Just because your dog gets bitten by an infected tick, it doesn't mean he'll develop Lyme disease, even if the infected tick feeds from him for 48 hours or more. Only about 10% of the dogs exposed to the bacteria that cause Lyme disease actually contract the illness. 

Symptoms of Lyme Disease

Dogs typically develop Lyme disease symptoms about two to five months after exposure to B. burgdorferi bacteria. The most common symptoms of Lyme disease in dogs are lameness, lethargy, loss of appetite, swelling in the joints and swelling in the lymph nodes. Dogs with Lyme disease will run a fever, typically between 103 and 105 degrees F.

Diagnosing Lyme Disease in Dogs

Your vet will need to perform blood tests in order to diagnose Lyme disease. Lyme disease diagnostic tests detect the antibodies your dog's immune system produces against the B. burgdorferi bacteria. However, this test isn't very accurate; your dog may test positive for Lyme disease even if he's merely been exposed, but not contracted, the illness, or if he's been vaccinated against the illness. Your dog may test negative for Lyme disease with this test, even if he has it.

A C6 antibody test can determine whether your dog has actually been exposed to Lyme disease, or if the antibodies in his blood are the result of a vaccination against the illness. However, there is no test that can confirm the accuracy of a standard blood test for Lyme disease. Your vet will perform a thorough physical exam and take a complete medical history; he'll also consider whether you live in or have recently visited an area considered high risk for Lyme disease infections. Armed with this supporting evidence, your vet will diagnose Lyme disease.

Treating Lyme Disease

Your vet will treat Lyme disease with tetracycline or another penicillin based antibiotic. Treatment typically lasts from 14 to 30 days and most dogs respond well to treatment. In some cases, however, infection becomes chronic. These dogs may need to remain in treatment for months, or for the rest of their lives.