Syphilis can be passed to subsequent sex partners during the first two years after the disease is contracted. After two years, the disease is unlikely to be transmissible to sex partners but can be passed from a woman to her unborn child. The first sign of syphilis infection, the primary stage, is usually a small painless sore at the site where the spirochete entered the body. This sore, called a chancre , appears two to six weeks after exposure and disappears spontaneously. Early symptoms may be either absent or so slight that they may go unnoticed.
Some people learn they are infected with syphilis through a blood test.
The secondary stage of syphilis may also go unnoticed by the infected person. Secondary symptoms appear two to six months after exposure to the disease and, like primary symptoms, will disappear without medical treatment. In the latent stage, patients are without clinical signs of infection. Signs of late or final stages of syphilis appear four to six years after initial contact. Heart disease, blindness, deafness, skin lesions, paralysis and central nervous system degeneration may develop.