Cause: A bacteria called treponema. This enters the body through tiny cracks in the skin or by penetrating mucus membranes, such as through oral sex, then lives and multiplies in the blood and other body fluids of the infected person. It is passed on by the fluid secreted from the characteristic sores or chancres.
Symptoms: The development of syphilis occurs in three stages. The symptoms are the same in men and women.
Stage one: Between one and twelve weeks after infection a hard, painless sore develops on or near the penis or vagina, or sometimes in the anus or mouth. It usually lasts two to three weeks.
Stage two: Two to six months after infection a skin rash appears all over the body. It may develop to form pimples or pustules. Flu-like symptoms may also occur. This lasts for two to six weeks. Sometimes these first two stages are not even noticeable. Natural antibodies are also produced in the body, which in some cases are sufficient to cure the disease.
Late stage: This may occur long after the other symptoms have disappeared, many years after infection. If untreated the treponema bacterium can affect other parts of the body, and damage the heart and brain in particular. Disfigurement and death can occur, though nowadays this is rare.
Treatment: Syphilis can be treated very effectively with penicillin if the disease is diagnosed early.