Borrelia burgdorferi

Using darkfield microscopy technique, this photomicrograph, magnified 400x, reveals the presence of spirochete, or “corkscrew-shaped” bacteria known as Borrelia burgdorferi, which is the pathogen responsible for causing Lyme disease. B. burgdorferi are helical shaped bacteria, and are about 10-25µm long. These bacteria are transmitted to humans by the bite of an infected deer tick, and caused more than 23,000 cases of Lyme disease in the United States during 2002.