Treponema pallidum
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Syphilis is caused by a spirochete organism, Treponema Pallidum, which has a thin, slow-moving, corkscrew-like body. Other variants of this family of Treponematoses include Treponema pertenue (yaws), Treponema endemicum (bejel), and Treponema carateum (pinta). Venereal syphilis is thought to have mutated from yaws by many supporters of the "Post-Columbian" origin theory. Syphilis is a very frail organism that cannot thrive outside the body and is crippled by simple physical and chemical elements such as heat, soap, and water. Because of these characteristics, its primary method of transmission is through direct contact of vulnerable mucous membranes during sex. Venereal syphilis presents itself in four (although most only refer to three) distinct stages:

As seen, if left untreated, syphilis affects the bones, heart, brain, nervous system and other organs of the body. In congenital syphilis, however, the disease is spread through infection of the mother to the child through the blood supply to the womb (most common when the mother is in the secondary to latent stages of the disease).


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Diagram of Treponema pallidum Treponema pallidum Treponema pallidum