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Syphilis Fact Sheet

What is syphilis?

Syphilis is a bacterial infection that is sexually transmitted.

Untreated, there are four stages through which syphilis progresses (each stage has its own signs and symptoms): primary, secondary, latent, and late.

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How do people get syphilis?

Syphilis can be transmitted through vaginal, anal, and oral sex. Syphilis is spread through direct contact with sores caused by the disease. Syphilis sores(called chancres) are usually found on the surface of the genitals and the anus, and inside the vagina and rectum. The sores can also develop on the mouth and lips.

A pregnant woman with syphilis can also pass the disease to her fetus while pregnant. This is why pregnant women should be tested for syphilis (most states require a syphilis test as part of a pregnant woman's health care).

Health care workers are at risk if a cut on the skin comes into contact with a syphilis sore.

Because syphilis bacteria are extremely fragile, they are not spread by contact with toilet seats, towels, eating utensils, bathtubs, or swimming pools.

How common is PID?

44,828 cases from all stages of syphilis were reported in 2009. Of these, nearly 14,000 were in the primary and secondary (P&S) stages where transmission to a partner most often occurs.

After declining for years, rates of P&S syphilis leveled off in the 1990s and increased every year between 2001 and 2009. Between 2005 and 2009 alone, rates of P&S syphilis in the U.S. surged by 59%. The most dramatic jump has occurred among men who have sex with men (MSM), who in 2009 accounted for just under two-thirds of P&S syphilis cases (up from 4% in 2000).

Reduce your risk

There are several things that can lower the risk of syphilis and other STDs:

  • Don't have sex while any sores, rashes, or other symptoms of syphilis are present.
  • Use condoms or other latex barrier (such as a dental dam) for each sex act (oral, anal, and vaginal).  A barrier should be put on before any sexual contact takes place.
  • Having sex with only one partner (who only has sex with you)
  • All partners of someone diagnosed with syphilis (of any stage) should be tested. Talk with your healthcare provider to see what STD tests might be recommended for you.
  • Talk to your partner

It can be hard to tell a partner that you have syphilis, but keep in mind that your partner can have it and not know. A person can be reinfected with syphilis once it's cured, so don't have sex again until all partners have been tested and, if needed, treated.


Syphilis can be diagnosed with blood tests, or by testing a sample taken from a syphilis sore. Healthcare providers also test fluid from the brain and spine if they suspect the central nervous system has been damaged by late stage syphilis.

Syphilis increases the risk for HIV infection, so anyone diagnosed with syphilis should also be tested for HIV.

Blood Tests

Soon after someone is infected, their body develops syphilis antibodies (substances produced by the immune system in response to an infection). A blood test can detect these antibodies: when a blood test is positive for syphilis antibodies, the results are usually confirmed with a second blood test.

Antibodies to syphilis can remain in the blood for years after someone is treated and cured, so a person who no longer has the infection may still test positive.


Syphilis in its early stages is very easily cured with a single injection of the antibiotic penicillin. Patients who have syphilis longer than one year may require additional doses (usually three injections of penicillin). It's important to treat syphilis early. Treatment will cure syphilis and stop additional damage, but won't reverse any complications that have already occurred (see Late Stage section).

Patients who are allergic to penicillin (and not pregnant) may be treated with other antibiotics.

Anyone treated for syphilis should not have sex until any sores or rashes have healed completely. Even after treatment, a person can be re-infected.

Even with a negative blood test, healthcare providers often go ahead and treat anyone who had sexual contact with a partner in the three month period before the partner was diagnosed with early syphilis.

What are the symptoms?

Primary Stage: 

Symptoms of primary syphilis usually develop within 10 to 90 days of infection, most often after about three weeks. The classic symptom is a single sore that is usually round, painless and raised off the skin (multiple sores are possible). The sore occurs where syphilis entered the skin and may appear on the penis, anus, or inside the vagina and rectum. Lasting 3 to 6 weeks, any sores that develop will go away on their own, but without treatment the person still has syphilis and can transmit it to others.

Secondary Stage:

Symptoms of the secondary stage include a rough, reddish-brown rash or spots on the palms of the hands or the soles of the feet. Rashes can develop on other parts of the body, including the neck and torso. Rashes related to syphilis can be mild, or similar to those caused by other diseases.

Other symptoms that might occur with secondary syphilis include swollen glands, headaches, fevers, patchy hair loss, and a general sense of not feeling well.

Latent Stage:

Latent (or hidden) stage of syphilis begins when symptoms from the primary and secondary stages end. During the latent stage, which can last for many years, a person has no symptoms of syphilis but still has the infection in his/her body.

Late Stage:

Even without treatment most people never progress to late (also called tertiary) stage syphilis. The late stage can occur 10-20 years (or more) after a person first contracts syphilis and can do serious damage to the organs, including the brain, nervous system, and heart. Symptoms can include blindness, paralysis, and loss of mental functioning. Sometimes the damage is so severe it results in death.


Centers for Disease Control and Prevention:

National Institute of Allergy and Infectious Diseases