Treponema pallidum is an extremely fragile helical bacterium (Spirochaete) that does not subsist in the air or at high temperatures (above 42 ° C). It is difficult to grow outside your host (humans and other animals), you can attack with penicillin. It is the cause of syphilis. Sexually transmitted disease that occurs with characteristic syphilitic cankers in the genitals and other areas (where the germ entered the body). Because they are painless and often located in the vagina, they can go unnoticed, being a source of infection. In later stages there may be whitish grayish spots or a skin rash, genitals, palms of the hands, soles of the feet or mouth. If it affects the eyes it can cause blindness. The infection can remain for a long time causing cardiovascular complications, in joints (osteoarthritis) or in the nervous system (aneurysm).