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Syphilis

Topic Overview

What is syphilis?

Syphilis is a sexually transmitted infection (STI) caused by the bacterium Treponema pallidum. If it's not treated by a doctor, it can get worse over time and cause serious health problems.

The infection can be active at times and not active at other times. When the infection is active, you have symptoms. When it's not active, you don't have symptoms, even though you still have syphilis. But even when you don't have symptoms, you can pass syphilis to others.

You don't have to have sexual intercourse to get syphilis. Just being in close contact with an infected person's genitals, mouth, or rectum is enough to expose you to the infection.

What causes syphilis?

Bacteria cause syphilis. They usually enter the body through the tissues that line the throat, nose, rectum, and vagina. Syphilis bacteria also can be transmitted by contact with the penis or vulva. A person with syphilis who has a sore or a rash can pass the infection to others. An infected pregnant woman can also pass syphilis to her baby.

Some things increase your chance of getting syphilis. They include:

  • Having unprotected sex (such as not using condoms or not using them correctly). This risk is high among men who have sex with other men.
  • Having more than one sex partner and living in an area where syphilis is common.
  • Having a sex partner who has syphilis.
  • Having sex with a partner who has many sex partners.
  • Trading sex for drugs or money.
  • Having HIV.

What are the symptoms?

You may not notice symptoms of syphilis. Sometimes they are the same as symptoms for other infections. This can cause someone with the infection to put off seeing a doctor. And it can make it harder for a doctor to tell if you have syphilis.

The four stages of syphilis have different symptoms.

  • Primary stage: One of the first signs is a painless open sore called a chancre (say "SHANK-er"). Because syphilis is usually spread when people have sexual contact, chancres are often found in the mouth, the anus, or the genital area. They may also be found wherever the bacteria entered the body.
  • Secondary stage: A skin rash and other symptoms may show up 2 to 12 weeks after a person is infected. At this stage, it is very easy to spread the infection through contact with the mouth, the anus, the genitals, or any area where there is a skin rash.
  • Latent stage: After the rash clears, a person may have a period with no symptoms. This is often called the "hidden stage." Even though symptoms go away, the bacteria that cause syphilis are still in the body and begin to damage the internal organs. This stage may be as short as 1 year or last from 5 to 20 years. Often, a woman with latent-stage syphilis doesn't find out that she has the infection until she gives birth to a child with syphilis.
  • Late (tertiary) stage: If syphilis is not found and treated in the early stages, it can cause other serious health problems. These can include blindness, problems with the nervous system and the heart, and mental disorders. It can also cause death.

How is syphilis diagnosed?

If you have sores, bumps, a rash, blisters, or warts on or around your genital or anal area, or if you think you were exposed to an STI, see your doctor.

He or she will do a physical exam and will ask you about your symptoms and your sexual history. You will probably have one or more blood tests to check for the infection. Because the open sores from syphilis make HIV infection more likely, you may also be tested for HIV.

To prevent babies from getting syphilis, experts recommend that all pregnant women have a syphilis blood test.

How is it treated?

Syphilis can be cured with antibiotics. Both you and any sex partners that you may have exposed to the infection will need to be treated.

It is important to know that syphilis is not a infection that you can treat on your own. It must be treated with medicine that only your doctor can give you. With treatment, you avoid other serious health problems. And treatment keeps you from spreading syphilis to others.

If a woman is pregnant and has untreated syphilis, it can cause miscarriage or stillbirth. It can also cause the baby to be born with the infection. This is called congenital syphilis.

At any stage of the infection, antibiotics work well to cure syphilis. They can't undo the damage already caused by late-stage syphilis. But they can help you avoid further problems from the infection.

How can you prevent syphilis?

There are some things you can do to lower your risk for getting syphilis. Whether you have never had the infection or if you have had it before and are trying to keep from getting it again, it is important to practice safer sex. Safer sex includes using condoms and using them correctly.

Cause

Syphilis is caused by the bacterium Treponema pallidum.

Transmission

Transmission of the bacteria usually occurs during vaginal, anal, or oral sex. The syphilis bacteria are passed from person to person through direct contact with:

Sores mainly occur on the external genitals, vagina, anus, or rectum. Sores can also occur on the lips and in or around the mouth. The bacteria most commonly enter the body through mucous membranes, usually in the area around the genitals and urinary system.

In rare cases, syphilis enters the body through openings in the skin, such as cuts and scrapes, or even through wet kisses, if the infected person has a sore on the mouth or lips. Syphilis may also be transmitted by using a needle previously used by an infected person. Syphilis can be transmitted through a blood transfusion. But this is very rare, because all donated blood in the United States and Canada is screened for some sexually transmitted infections (STIs). And syphilis bacteria cannot survive more than 24 to 48 hours in blood stored using modern blood-banking methods.

A pregnant woman with syphilis can pass the infection through the placenta and infect her baby any time during pregnancy or delivery (congenital syphilis).

Syphilis cannot be spread through casual contact with toilet seats, door knobs, swimming pools, hot tubs, bathtubs, shared clothing, or eating utensils.

Having been infected with syphilis in the past does not protect a person from becoming infected again.

Incubation period

An incubation period is the time between exposure to a disease and the first symptom. A skin sore called a chancre is usually the first symptom of sexually transmitted syphilis. A chancre appears between 3 weeks to 3 months after a person has been infected with syphilis.

Contagious period

A person with syphilis can easily pass the infection (is contagious) to physically intimate partners when primary- or secondary-stage sores are present. But the person may be contagious for years, off and on, and is always contagious whenever an open sore or skin rash from syphilis is present.

Symptoms

Syphilis develops in four stages, each with a different set of symptoms.

Primary stage

During the primary stage of syphilis, a sore (chancre) that is usually painless develops at the site where the bacteria entered the body. This commonly occurs within 3 weeks of exposure but can range from 10 to 90 days. A person is highly contagious during the primary stage.

  • In men, a chancre often appears in the genital area, usually (but not always) on the penis. These sores are often painless.
  • In women, chancres can develop on the outer genitals or on the inner part of the vagina. A chancre may go unnoticed if it occurs inside the vagina or at the opening to the uterus (cervix). The sores are usually painless and are not easily seen.
  • Swelling of the lymph nodes may occur near the area of the chancre.
  • A chancre may also occur in an area of the body other than the genitals.
  • The chancre usually lasts for 3 to 6 weeks, heals without treatment, and may leave a thin scar. But even though the chancre has healed, syphilis is still present and a person can still pass the infection to others.

Secondary stage

Secondary syphilis is characterized by a rash that appears 2 to 12 weeks after the chancre develops and sometimes before it heals. Other symptoms may also occur, which means that the infection has spread throughout the body. A person is highly contagious during the secondary stage.

A rash often develops over the body and commonly includes the palms of the hands and the soles of the feet.

  • The rash usually consists of reddish brown, small, solid, flat or raised skin sores that are less than2 cm (0.8 in.) across. But the rash may look like other more common skin problems.
  • Small, open sores may be present on mucous membranes. The sores may contain pus. Or moist sores that look like warts (called condyloma lata) may be present.
  • In dark-skinned people, the sores may be a lighter color than the surrounding skin.

The skin rash usually heals within 2 months on its own without scarring. After healing, skin discoloration may occur. But even though the skin rash has healed, syphilis is still present and a person can still pass the infection to others.

When syphilis has spread throughout the body, the person may have:

  • A fever.
  • A sore throat.
  • A vague feeling of weakness or discomfort throughout the body.
  • Weight loss.
  • Patchy hair loss, especially in the eyebrows, eyelashes, and scalp hair.
  • Swelling of the lymph nodes.
  • Nervous system symptoms of secondary syphilis, which can include neck stiffness, headaches, irritability, paralysis, unequal reflexes, and irregular pupils.

Latent (hidden) stage

If untreated, an infected person will progress to the latent (hidden) stage of syphilis. The latent stage is defined as the year after a person becomes infected. After the secondary-stage rash goes away, the person will not have any symptoms for a time (latent period). The latent period may be as brief as 1 year or range from 5 to 20 years.

Often during this stage, an accurate diagnosis can only be made through blood testing, the person's history, or the birth of a child with congenital syphilis.

A person is contagious during the early part of the latent stage and may be contagious during the latent period when no symptoms are present.

Relapses

Some people with syphilis have a relapse of the infection during its latent stage. A relapse means the person was symptom-free but then started having symptoms again. Relapses can occur several times.

When relapses no longer occur, a person is not contagious through contact. But a woman in the latent stage of syphilis may still pass the infection to her developing baby and may have a miscarriage or a stillbirth or give birth to a baby infected with congenital syphilis.

Tertiary (late) stage

This is the most destructive stage of syphilis. If untreated, the tertiary stage may begin as early as 1 year after infection or at any time during a person's lifetime. A person with syphilis may never experience this stage of the illness.

During this stage, syphilis may cause serious blood vessel and heart problems, mental disorders, blindness, nerve system problems, and even death. The symptoms of tertiary (late) syphilis depend on the complications that develop. Complications of this stage include:

Congenital syphilis

Congenital syphilis refers to syphilis passed from a mother to her baby during pregnancy or during labor and delivery. The U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Preventive Services Task Force strongly recommend that all pregnant women be screened for syphilis because of the severe consequences of being pregnant while infected or having a child born with congenital syphilis. Screening should be done:footnote 1, footnote 2

  • At the first prenatal visit for all pregnant women.
  • At the beginning of the third trimester of pregnancy and again at delivery for women who are at high risk for syphilis.

Congenital syphilis increases the risk of fetal death and medical complications in newborns. Syphilis enters the fetal blood system through the placenta, causing infection in the newborn or death of the fetus. Symptoms of congenital syphilis include:

  • A highly contagious watery discharge from the nose.
  • Painful inflammation.
  • Contagious rash that frequently appears over the palms of the hands and soles of the feet.
  • Reduced red blood cells in the blood (anemia).
  • Enlarged liver and spleen.
  • Swelling of the lymph nodes.
  • Failure to grow and develop normally (failure to thrive).

Because there are other conditions with similar symptoms, an accurate diagnosis is important for treatment.

What Happens

About 3 weeks-although the range is from 10 to 90 days-after a person is infected with syphilis, a sore (chancre) that is usually painless often appears on the genitals. This first stage in the course of syphilis is referred to as the primary stage. The chancre usually heals without treatment in 3 to 6 weeks.

If syphilis is not treated during the primary stage, it often progresses to later stages.

In the secondary stage of syphilis, a skin rash will usually develop about 2 to 12 weeks after the chancre appears. The symptoms usually disappear without treatment within 2 months.

After the rash clears, a person may have a period with no symptoms. This symptom-free period is called the latent (hidden) stage. Even though symptoms disappear, the bacteria that cause syphilis remain in the body and begin to damage the internal organs. The latent period may be as brief as 1 year or range from 5 to 20 years.

A person is contagious during the primary and secondary stages and may still be contagious during the early part of the latent stage. During this time, symptoms of the second stage of syphilis may reappear. This is called a relapse and can occur several times.

If not detected and treated, syphilis may then progress to the tertiary (late) stage, the most destructive stage of syphilis. During this stage, syphilis may cause serious blood vessel and heart problems, mental disorders, blindness, nerve system problems, and even death. It may begin as early as 1 year after infection or at any time during the infected person's life. About one-third of untreated people who are infected with syphilis will have the complications of tertiary (late) syphilis. Any organ system (such as the central nervous system) may become involved.

Complications of tertiary (late) syphilis include:

Congenital syphilis refers to syphilis passed from the mother to the baby during pregnancy or during labor and delivery. Congenital syphilis can cause complications in newborns and children.

What Increases Your Risk

Your risk of syphilis increases if you:

  • Have unprotected sex (do not use condoms or do not use them correctly). This risk is especially high among men who have sex with other men (MSM).
  • Have multiple sex partners, particularly if you live in an area of the country where syphilis is more common.
  • Have a sex partner who has syphilis.
  • Have sex with a partner who has multiple sex partners.
  • Exchange sex for drugs or money.
  • Have human immunodeficiency virus (HIV) infection and engage in any of the behaviors listed above.

Syphilis is contagious whenever an open sore or skin rash is present. The risk of being infected with syphilis from a single sexual encounter with an infected partner is approximately 3% to 10%.footnote 3

Infection with syphilis also increases a person's risk of being infected with HIV. Syphilis causes open sores on the genitals that allow the HIV infection to enter the body easily. Syphilis is in general more common in people who are also infected with HIV.

When To Call a Doctor

Call to make an appointment if you:

  • Have sores, bumps, rashes, blisters, or warts on or around the genital or anal area or on any area of the body where you think they could be caused by a sexually transmitted infection (STI).
  • Think you have been exposed to a STI.

In most areas, public health clinics or health departments are able to diagnose and provide low-cost assessment and treatment of early syphilis and other sexually transmitted infections (STIs).

For more information about symptoms of other sexually transmitted infections, see the topic Exposure to Sexually Transmitted Infections.

Watchful waiting

Watchful waiting, which means taking a wait-and-see approach, is not appropriate if you think you were exposed to or have syphilis or another sexually transmitted infection (STI). Any symptoms or other changes that suggest syphilis or another STI should be evaluated by a doctor. If you suspect a syphilis infection:

  • Make an appointment with your doctor. Early treatment can reduce the complications of syphilis and prevent the spread of the infection to others.
  • Do not have sexual intercourse or other sexual contact until you have been treated by a doctor.

If you are diagnosed with syphilis, your sex partner(s) will need to be treated also.

All states require doctors to report newly diagnosed cases of syphilis (all stages) to health authorities.

Who to see

Your primary doctor can diagnose and treat syphilis.

Health professionals who can diagnose and treat sexually transmitted infections (STIs) include:

Complications of secondary or later stage syphilis may require treatment by an infectious disease specialist.

In most areas, public health clinics or county health departments are able to diagnose and provide low-cost or free treatment of early syphilis and other STIs.

Exams and Tests

Diagnosis of syphilis includes a medical history and a physical exam. Your doctor may ask you questions such as:

  • Do you think you have been exposed to any sexually transmitted infections (STIs)?
  • What are your symptoms?
  • Do you have sores in your genital area or anywhere else on your body?
  • Do you or your partner engage in sexual behaviors that put you at risk, such as having sex without a condom or having more than one sex partner?
  • Have you had an STI in the past?

The physical exam may include:

  • A careful examination of the skin and mouth to look for any rash or other abnormalities.
  • For women, a pelvic exam to look for signs of syphilis. During the pelvic exam, your doctor will look for abnormal sores in the vagina or on the vulva, labia, rectal area, and inner thighs. These sores occur during the primary stage of syphilis.
  • For men, a genital exam to look for signs of syphilis.
  • For newborns, an examination of both the newborn and the mother for symptoms. The evaluation for congenital syphilis begins with a review of the mother's health and testing the mother for syphilis.

The diagnosis of syphilis is usually confirmed with one of several blood tests. This is especially true if no sores are present. If sores are present, a doctor may look at the fluid from one of the sores with a microscope to see whether syphilis bacteria are present (dark-field examination).

In the diagnosis of the primary and secondary stages of syphilis, lumbar puncture (spinal tap) is needed in some cases.

Additional testing should be done to find out if other sexually transmitted infections are present, especially:

The diagnosis of syphilis can be delayed or complicated because its symptoms are very similar to those of many other diseases and are sometimes not recognized. Syphilis has historically been called "the great imitator."

Early detection

Screening for syphilis is strongly recommended for pregnant women and for people who are at increased risk for the infection.

People at high risk of contracting syphilis include those who:

  • Have unprotected sex (do not use condoms or do not use them correctly). This risk is especially high among men who have sex with men (MSM).footnote 4
  • Have multiple sex partners, particularly if they live in an area of the country where syphilis is more common.
  • Have a sex partner who has syphilis.
  • Have sex with a partner who has multiple sex partners.
  • Exchange money or drugs for sex (prostitution).
  • Have human immunodeficiency virus (HIV) infection.

The U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Preventive Services Task Force strongly recommend that pregnant women be screened for syphilis because of the severe consequences of being pregnant while infected or having a child born with congenital syphilis. Screening should be done:footnote 1, footnote 2

  • At the first prenatal visit for all pregnant women.
  • During the third trimester and again at delivery for pregnant women who have an increased risk for syphilis.

Treatment Overview

Prompt treatment of syphilis is needed to cure the infection, prevent complications, and prevent the spread of the infection to others.

  • Antibiotics effectively treat syphilis during any stage.
  • Antibiotic treatment cannot reverse the damage caused by complications of late-stage syphilis, but it can prevent further complications.
  • Follow-up blood tests are done to make sure that treatment has been effective.
  • Sex partners of a person who has syphilis need to be examined, tested, and treated for syphilis. Antibiotic treatment is recommended for all exposed sex partners.

Penicillin is the preferred drug for treating syphilis. Penicillin is the standard therapy for the treatment of neurosyphilis, congenital syphilis, or syphilis acquired or detected during pregnancy. If you are allergic to penicillin, make sure you tell your doctor. Your doctor will still be able to treat the syphilis but may consult with a specialist on the best antibiotic choice.

Prevention

Self-care can lower your risk for an initial infection of or reinfection with syphilis or other sexually transmitted infections (STIs).

  • Practicing safer sex to prevent STIs. Limit your sex partners, know whether your partner engages in risky sexual behaviors.
  • Use a condom during sex. Using a condom is the best way to protect yourself from STIs.

Medications

The treatment of syphilis and other sexually transmitted infections (STIs) is complex. If taken properly, antibiotic treatment with penicillin will usually cure a syphilis infection. If syphilis has progressed to the tertiary stage, antibiotics can prevent further complications. But they cannot reverse damage that has already occurred. Prompt antibiotic treatment will decrease complications and prevent the spread of the infection.

Exposed sex partners should be treated for syphilis. The chancres in syphilis can make transmission of HIV more likely. So testing for both syphilis and HIV should be done.

Medicine choices

What to think about

In rare cases, the first attempt at treatment does not cure the syphilis infection. Follow-up blood tests are needed to be sure the infection is cured.

Some types of syphilis can't be treated by (are resistant to) certain antibiotics. If your doctor finds that your syphilis is resistant to the drug you are taking, you will be tested so that your doctor can prescribe another antibiotic to cure the infection.

References

Citations

  1. Centers for Disease Control and Prevention (2015). Sexually transmitted diseases treatment guidelines, 2015. MMWR, 64(RR-03): 1-137. http://www.cdc.gov/std/tg2015. Accessed July 2, 2015. [Erratum in MMWR, 64(33): 924. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6433a9.htm?s_cid=mm6433a9_w. Accessed January 25, 2016.]
  2. U.S. Preventive Services Task Force (2009). Screening for syphilis infection in pregnancy: U.S. Preventive Services Task Force reaffirmation recommendation statement. Annals of Internal Medicine, 150(10): 705-709.
  3. Eckert LO, Lentz GM (2012). Infections of the lower and upper genital tracts: Vulva, vagina, cervix, toxic shock syndromes, endometriosis, and salpingitis. In GM Lentz et al., eds., Comprehensive Gynecology, 6th ed., pp. 519-559. Philadelphia: Mosby.
  4. Centers for Disease Control and Prevention (2015). Sexually transmitted disease surveillance 2014. U.S. Department of Health and Human Services. http://www.cdc.gov/std/stats14/surv-2014-print.pdf. Accessed April 29, 2016.

Other Works Consulted

  • American Academy of Pediatrics (2015). Syphilis. In DW Kimberlin et al., eds., Red Book: 2015 Report of the Committee on Infectious Diseases, 30th ed., pp. 755-768. Elk Grove Village, IL: American Academy of Pediatrics.
  • Cox D, Ballard RC (2010). Syphilis. In SA Morse et al., eds., Atlas of Sexually Transmitted Diseases and AIDS, 4th ed., pp. 111-140. Philadelphia: Saunders.

Credits

ByHealthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
E. Gregory Thompson, MD - Internal Medicine
Martin J. Gabica, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kevin C. Kiley, MD - Obstetrics and Gynecology

Current as ofNovember 27, 2017

Current as of: November 27, 2017

Author: Healthwise Staff

Medical Review: Kathleen Romito, MD - Family Medicine & E. Gregory Thompson, MD - Internal Medicine & Martin J. Gabica, MD - Family Medicine & Adam Husney, MD - Family Medicine & Kevin C. Kiley, MD - Obstetrics and Gynecology