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Student Health Services


What is Syphilis?

Syphilis is caused by a spirochete called Treponema pallidum. Syphilis can progress through four major stages, beginning 2 weeks to a month after infection. The first stage, or primary syphilis, is nearly always characterized by the appearance of a painless sore wherever the spirochete entered the body. The sore, called a chancre, begins as a reddish bump that develops into a pimple. It then opens and ulcerates, often oozing pus until a scab develops. The chancre is sometimes surrounded by a pink border. This sore is infested with the treponema organism, and the individual is highly infectious at this stage. Usually the chancre appears on the genitals, although it can appear on the mouth, anal area, and on fingers or breasts. In women it frequently occurs on the inner vaginal wall or cervix and sometimes in the rectum. Since it is relatively painless, it may not be noticed. Within 4 to 6 weeks, the chancre heals even without treatment and there may be no further symptoms for up to 6 months.

The next stage, secondary syphilis, usually begins with a bumpy skin rash, accompanied by general symptoms of illness such as fever, swollen lymph nodes of the neck, nausea, headache, sore throat, loss of scalp hair, and loss of appetite. More moist sores may appear around the genitals or anal region. Again, even without treatment, the symptoms eventually abate within a few weeks, and the disease enters its latent stage. It is estimated that slightly more than half of untreated syphilis victims remain in the latent stage for the rest of their lives.

People who progress to the tertiary syphilis stage usually face serious complications resulting from the spirochete infecting inner tissues and organs. It may attack the heart, brain and spinal cord, eyes, joints, and numerous other areas, leading to life-threatening disease, blindness, psychosis, or paralysis. Although modern medical treatment has greatly reduced the number of syphilis cases progressing to the tertiary stage, they still occur. In later tertiary stages, the disease typically cannot be transmitted to others.

Testing and Treatment

A blood test is used to determine if an individual is infected with Syphilis. Because the blood tests look for antibodies, these tests can be performed during any stage of infection. If the result is positive, an individual is treated with penicillin. For individuals allergic to penicillin, other antibiotics can be used.


Refraining from oral, anal, and vaginal sex will prevent the risk of contracting syphilis. If you are sexually active, having sex with only one uninfected partner will reduce your risk of contracting an infection.

Latex or polyurethane condoms can be used during oral, anal and to also reduce the risk. Condoms will not provide complete protection as syphilis can be transmitted through the open chancre which may be located in an area not covered by the condom.