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Reviewed by the Faculty of Harvard Medical School
Syphilis
  • What Is It?
  • Symptoms
  • Diagnosis
  • Expected Duration
  • Prevention
  • Treatment
  • When To Call a Professional
  • Prognosis
  • Additional Info
  • What Is It?

    Syphilis is a sexually transmitted disease (STD) caused by a type of bacteria called Treponema pallidum. In its earliest stage, syphilis produces an open sore (ulcer) that leaks fluid filled with syphilis bacteria. Syphilis can be transmitted by contact with this ulcer or other infectious sores that form later in the disease, usually during vaginal, oral or anal sex. If untreated, syphilis moves through a series of stages that affect different parts of the body, although the stages can overlap:

    Pregnant women with syphilis can pass the bacteria to their babies, causing a condition known as congenital syphilis. Congenital syphilis causes a variety of skin and organ problems in infants, and it can be deadly. Pregnant women with syphilis also have about a 40% chance of having a baby that is stillborn.

    In 2005, more than 33,000 cases of syphilis were diagnosed in the United States. In recent years, the incidence of syphilis has increased in the U.S. among men who have sex with men. Most cases occurred in people between the ages of 20 and 39. Rates of congenital syphilis have been declining. The incidence fell by 12% between 2004 and 2005 in the U.S. with about 400 cases reported each year.

    If you are infected with syphilis, it may be easier for you to become infected with HIV. If you already have HIV, a syphilis infection may make you more likely to spread HIV to others.

    Symptoms

    The symptoms of syphilis vary depending on the stage of the illness:

    Primary syphilis – Usually, a single ulcer (chancre) appears at the site where the bacteria entered the body. The genitals are the most common location for chancres to develop, but these ulcers also can form around the mouth or anus. The chancre is firm and painless, and it oozes fluid that contains syphilis bacteria. Sometimes, lymph nodes near the ulcer become enlarged, but remain painless. The chancre of primary syphilis usually heals after one to five weeks, although the person remains infected.

    Secondary syphilis – Typical symptoms of secondary syphilis are:

    Without treatment, rash symptoms usually go away after two to six weeks.

    Other symptoms can include:

    Without treatment, these other symptoms generally last about one year.

    Latent stage – This stage does not cause any symptoms.

    Tertiary syphilis – In this stage, syphilis causes symptoms related to severe organ damage. These symptoms can include:

    Diagnosis

    If your doctor suspects that you have syphilis, he or she will look for any of the typical symptoms of the disease, especially for a chancre in the genital area. Your doctor can diagnose syphilis by taking a sample of fluid from a suspicious ulcer and having that fluid examined under a microscope for the presence of syphilis bacteria.

    Your doctor also may order blood tests to check for certain antibodies that are present in people with syphilis. However, in some cases, people without syphilis test positive for these antibodies. A positive test may have to be confirmed with a second blood test.

    Because of the high risk of HIV infection in people with syphilis, public-health officials recommend that all people infected with syphilis should be tested for HIV infection.

    Expected Duration

    Unless treated, syphilis is a lifelong illness.

    Prevention

    A person who has symptoms of primary or secondary syphilis can pass a syphilis infection to his or her sex partner. During sexual intercourse, the bacteria can pass from sores to the uninfected sexual partner through tiny breaks in the skin. To prevent this from happening, any sexually active person who is not having sex with just one uninfected person should always use a condom during sexual activity. Every pregnant woman should have a blood test for syphilis to prevent passing the infection to her baby.

    Treatment

    People with primary syphilis can usually be cured with a single injection of penicillin. People in later stages require longer treatment with penicillin. All sex partners of people with syphilis should be treated as well. Babies born with congenital syphilis should be treated with a course of penicillin for 10 days.

    When To Call a Professional

    Call your doctor if you develop any of the symptoms of syphilis, especially if you are pregnant. If you have a sex partner who is diagnosed with syphilis, call your doctor immediately so that you can be treated for syphilis.

    Prognosis

    With proper penicillin treatment, early syphilis infection can be cured without causing permanent damage. Although later stages of syphilis also respond to penicillin, the antibiotic will not repair any organ damage caused by the disease. Without treatment, about one-third of patients with latent syphilis develop tertiary syphilis, and these patients risk severe organ damage and death.

    Additional Info

    CDC National Prevention Information Network (NPIN)
    National Center for HIV, STD and TB Prevention
    P.O. Box 6003
    Rockville, MD 20849-6003
    Toll-Free: 1-800-458-5231
    Fax: 1-888-282-7681
    TTY: 1-800-243-7012
    E-Mail: info@cdcnpin.org
    http://www.cdcnpin.org/

    American Social Health Association
    P.O. Box 13827
    Research Triangle Park, NC 27709
    Phone: 919-361-8400
    Fax: 919-361-8425
    E-Mail: std-hivnet@ashastd.org
    http://www.ashastd.org/

    Last updated July 13, 2007