Syphilis is a sexually transmitted infection caused by the spirochete bacteria Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact however it may also be transmitted from mother to fetus during pregnancy or at birth resulting in congenital syphilis. Other human diseases caused by related Treponema pallidum include yaws (subspecies pertenue), pinta (subspecies carateum) and bejel (subspecies endemicum). The signs and symptoms of syphilis vary depending in which of the four stages it presents (primary, secondary, latent, and tertiary)...