English: The spirochete is a form of bacteria that results in lyme disease. It is characterized by its spiral formation. In addition to its spring-like shape, a spirochetal bacteria has filaments on the outside of its protoplasma. These filaments allow the bacteria to move while continuously rotating in place. Such placement of the flagella on a spirochete makes it easier for it to move throughout the bloodstream. Spirochetal bacteria also have the ability to cloak themselves within the bilayer of a cell, thereby avoiding detection from the immune system. This form of evasion makes it possible for a spirochete to remain dormant for long periods of time (by invading intracellular spaces).