My dog has recently been diagnosed with Lyme disease. I was wondering how fatal it is. Can I contract it from him or only from tick bites?

Katie

Lyme disease is caused by Borrelia burgdorferi, an organism similar to the bacterium that causes syphilis. Lyme disease in humans can take several forms, often called stages. The first stage is manifest by a rash called "erythema chronicum migrans." An enlarging red lesion develops at the site of the tick bite. As it expands, over several days, there is often partial clearing of the center of the lesion, creating a "bull's-eye" appearance, which is classic for Lyme disease. In the second stage, the organism disseminates to various parts of the body. Some people develop scattered lesions that are similar to the initial "bull's-eye." At this stage, there can be a wide variety of symptoms, including meningitis (infection of the membranes covering the brain and spinal cord), nerve damage, headache, fever, hepatitis (liver infection) and a host of other less common findings. In the third stage, also called persistent infection, arthritis and chronic nervous-system changes can be seen. In most people, the arthritis resolves, but some develop chronic or recurrent inflammation of the joints. In other patients, or in some with arthritis, a chronic nervous-system disorder develops. There can be loss of memory, decreased concentration, mood changes or language problems.

Lyme disease does not seem to develop in wild animals, but it has been reported in dogs and other domesticated animals. Several medical-research studies have looked at Lyme disease in dogs. Their disease has various symptoms, with arthritis the most common. Lyme disease seems to be a bit more difficult to treat in dogs than in people. In humans, at least in the early stages, Lyme disease is usually cured with a single course of antibiotics. In dogs, the organism is seldom totally eradicated with antibiotics. The symptoms commonly recur in dogs after the treatment is discontinued.

I do not think it would be likely for your dog to die of Lyme disease. He just may need several courses of antibiotics to control the infection. As to the chance that you will catch Lyme disease from your dog, I can tell you that Lyme disease is transmitted by the bite of a tick, and there has been no known direct person-to-person or animal-to-person transmission.