Fast Facts

  • Syphilis is a bacterial infection, caused by the bacteria Treponema pallidum.
  • Syphilis is passed on when infected lesions come in contact with the soft skin of the mucous membrane found inside the vagina, urethra or with an abrasion during vaginal, oral, and anal sex, even if there is no sexual penetration.
  • There are four stages through which untreated syphilis progresses, each stage with its own unique signs and symptoms: primary, secondary, latent, and tertiary (or late).
  • While curable with antibiotics, complications that may develop in later stages cannot be reversed with treatment, including serious damage to the brain, heart, nervous system, and even death.

How common is syphilis?

According to the Centers for Disease Control and Prevention (CDC) There were There were more than 115,000 syphilis cases in 2018. The number of primary and secondary syphilis cases—the most infectious stages—increased 14 percent to more than 35,000 cases, the highest number reported since 1991.

How is it transmitted?

Sexual transmission

  • Syphilis can be passed on when infected lesions come in contact with the soft skin of the mucous membrane found inside the vagina, urethra or with an abrasion during vaginal, oral and anal sex, even if there is no sexual penetration.
  • It is most easily spread during the first (primary) stage because symptoms usually go unnoticed.
  • Syphilis can also be contracted from exposure to lesions or syphilitic warts during the secondary stage.
  • If warts are present, they may easily spread the syphilis bacteria.
  • Because symptoms of secondary syphilis can recur, a person who has entered the latency stage of syphilis can still transmit the disease.

Nonsexual transmission

  • Because syphilis bacteria are extremely fragile, they cannot be spread during contact with objects such as toilet seats or towels.
  • People, especially healthcare workers, can be at risk for syphilis if an abrasion or cut on the skin comes into contact with a syphilitic lesion


  • Syphilis can be transmitted during pregnancy or during childbirth from a mother to her infant.

What are the symptoms?

Primary Syphilis

  • Chancre: The primary stage of syphilis is usually marked by the appearance of a single sore, known as a chancre, within 10 to 90 days after contact with the bacteria at the site of infection. It is usually appears as a single, painless sore, that is raised or elevated.
  • Chancres may be found: outside the genitals, including the penis, scrotum and vagina; inside the vagina or rectum; at or around the anus; or, on the lips or in the mouth, though this is not as common. The sore can last from three to six weeks.
  • The chancre will go away with or without treatment. Without treatment, the person will still have syphilis and can transmit it to others.

Secondary Syphilis

  • The secondary stage of syphilis can develop 17 days to 6 1/2 months after infection.
  • Symptoms can last from 2 to 6 weeks.
  • Symptoms can include: a rough, reddish-brown rash that appears on the palms of your hands or the soles of your feet, which normally does not itch; rashes on other parts of the body, including the neck, head and torso; condylomata lata or syphilitic “warts”, moist, raised or elevated skin lesions, may be found in the anus or genital area; “mucous patches,” flat, round, grayish-white sores, can appear on the mouth, throat, and cervix; patchy loss of hair on the head and other parts of the body; or, a general sense of ill health.
  • Symptoms of secondary syphilis will clear up with or without treatment, but the disease will still be present if untreated. It will then enter into a latent stage, which has no signs or symptoms.

Latent Stage

  • Latent syphilis is defined as the time where there are no signs or symptoms of the disease
  • Develops from two to 30+ years after infection.
  • Because there are no signs or symptoms, the only way to test for infection during the latent period is by blood test.
  • A relapse of secondary syphilis can occur once the disease has entered the latent stage. This normally will happen during the first two years of latency.

Late Stage (Tertiary)

  • Symptoms of late stage or tertiary syphilis can occur 2 to 30+ years after infection.
  • Complications during this stage can include: gummas (small bumps or tumors that can develop on the skin, bones, liver or any other organ), problems with heart and blood vessels, or chronic nervous system disorders, such as blindness, insanity and paralysis.
  • If treated during this period, gummas will usually disappear. Though treatment at this phase will cure the disease and stop future damage to the body, it cannot repair or reverse the damage that occurred before treatment.

Congenital Syphilis

  • A mother infected with syphilis can pass the disease to her unborn child, either during pregnancy or in childbirth. A newborn infected in this manner has congenital syphilis.
  • Early signs generally appear from three to eight weeks after a baby is born.
  • Even though these symptoms develop soon after birth, most cases go unnoticed until late congenital symptoms appear in childhood or adolescence.
  • Late congenital syphilis has similar symptoms to tertiary syphilis in adults, though heart complications rarely occur in cases of congenital syphilis

How is syphilis diagnosed?

Syphilis can be detected by blood tests, which looks for antibodies, or by testing fluid taken from lesions or swollen lymph nodes, which occur during primary or secondary syphilis. Tests on the lymphatic fluid or lesions look for antigens.

Darkfield Exam
This test uses a fluid sample taken from the chancre during primary syphilis or from symptoms that occur during secondary syphilis found in areas such as the vagina or the urethra. The sample is then viewed under a microscope. This test can only be done during primary or secondary syphilis, when sores, lesions & warts are present.

Blood Tests
Blood tests used to detect syphilis. These tests can be done in all stages of syphilis. There is a possibility of a false positive, particularly if the person tested has had syphilis before. A test may also be a false positive result if you are pregnant, have rheumatoid arthritis, use heroin, or have hepatitis, influenza or pneumonia.

Another test uses cerebrospinal (involving the brain and spinal chord) fluid and is usually done if a person has damage to their central nervous system.

Testing in infants
If no signs and symptoms are found at birth, a blood test should be performed every 2 to 3 months on the infant until the test comes back negative. This is because an infant may test positive for syphilis and not be infected until the mother’s antibodies, transmitted during pregnancy, clear the infant’s body.

How is syphilis treated?

  • The preferred treatment for syphilis is penicillin. If you are allergic to penicillin, your healthcare provider can suggest another antibiotic.
  • If you have HIV, tell your healthcare provider. The antibiotic may not be as effective.
  • Penicillin is the only recommended treatment for pregnant women. If you are pregnant and are allergic to penicillin, talk to your healthcare provider. They may want to use a process called desensitization that may allow a person to take penicillin.
  • Infants should be checked carefully at birth. Treatment can vary for many reasons. For more information about testing and treatment of infants, talk with your healthcare provider, or visit your local health department.

Treatment Follow Up

  • Take all medications as directed.
  • All partners should be examined and treated.
  • Do not have sex until you and your partner(s) have been treated and cured.
  • After treatment for primary or secondary syphilis, it is recommended that a person be retested after 6 months, and once again after a year.
  • If you are treated in the latent period, follow up tests are recommended after 6 months, 12 months & again at 24 months.
  • People who are infected with syphilis and also have HIV, should be retested every 3 months for 2 years.

What does it mean for my health?

Left untreated, syphilis can cause blindness, paralysis, and problems with your bones and internal organs, including your heart.

How can I reduce my risk?

Latex condoms for vaginal and anal sex. Condoms may protect the penis or vagina from infection, but do not protect from contact with other areas such as the scrotum or anal area.

Several barrier methods can be used to reduce the risk of transmission of syphilis during oral sex. A non-lubricated condom can be used for mouth-to-penis contact. Household plastic wrap, a dental dam, or a latex condom cut-up and opened flat can reduce the risk of transmission during mouth-to-vulva/vagina or oral-anal (rimming) contact.

How do I tell my partner?

Telling a partner can be hard, but keep in mind that some people with syphilis don’t know they have it. It’s important that you talk to your partner as soon as possible so she or he can get treatment. Also, it is possible to pass syphilis back and forth, so if you get treated and your partner doesn’t, you may get infected again.

The One-Two Punch: Knocking Out HIV and Syphilis Co-infection initiative offers downloads of a video and a collection of posters and social media content to encourage individuals to talk with health care professionals about testing for both infections.

Poster about HIV and syphilis

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