Syphilis is an infection by the Treponema pallidum bacteria that is transmitted by direct contact with a syphilitic sore on the skin, and in mucous membranes. A sore can occur on the vagina, anus, rectum, lips, and mouth. It is most likely to spread during oral, anal, or vaginal sexual activity. Rarely, it can be passed on through kissing. The first sign is a painless sore on the genitals, rectum, mouth, or skin surface. Some people do not notice the sore because it doesn’t hurt. These sores resolve on their own, but the bacteria remain in the body if not treated. The bacteria can remain dormant in the body, sometimes for decades, before returning to damage organs, including the brain.
The history of syphilis has been well studied, but the exact origin of the disease is unknown. There are two primary hypotheses: one proposes that syphilis was carried to Europe from the Americas by the crew of Christopher Columbus as a by-product of the Columbian exchange, while the other proposes that syphilis previously existed in Europe but went unrecognized. These are referred to as the “Columbian” and “pre-Columbian” hypotheses.
The first written records of an outbreak of syphilis in Europe occurred in 1494/1495 in Naples, Italy, during a French invasion. Because it was spread by returning French troops, the disease was known as “French disease”, and it was not until 1530 that the term “syphilis” was first applied by the Italian physician and poet Girolamo Fracastoro. The causative organism, Treponema pallidum, was first identified by Fritz Schaudinn and Erich Hoffmann in 1905.The first effective treatment (Salvarsan) was developed in 1910 by Sahachirō Hata in the laboratory of Paul Ehrlich which was followed by the introduction of penicillin in 1943. Many famous historical figures including Franz Schubert and Édouard Manet are believed to have had the disease.
Internationally, the prevalence of syphilis varies by region. Syphilis remains prevalent in many developing countries and in some areas of North America, Asia, and Europe, especially Eastern Europe. The highest rates are in South and Southeast Asia, followed closely by sub-Saharan Africa. The third highest rates are in the regions of Latin America and the Caribbean. In some regions of Siberia, as of 1999, prevalence was 1300 cases per 100,000 population.
Age distribution of syphilis
Syphilis is most common during the years of peak sexual activity. Most new cases occur in men and women aged 20-29 years. In 2013, the rate of primary and secondary syphilis was highest in people aged 25-29 years (27 per 100,000).
The incidence of congenital syphilis has increased to 11.6 cases per 100,000 live births in 2014, the highest congenital syphilis rate reported since 2001. The number of congenital syphilis cases declined in the United States during 2008-2012, from 446 to 334 cases (10.5 to 8.4 cases per 100,000 live births) but is increasing; from 2012-2014, the number of reported congenital syphilis cases in the United States increased from 334 to 458.
Sex distribution of syphilis
Men are affected more frequently with primary or secondary syphilis than women. This difference has varied over time. Male-to-female ratios of primary and secondary syphilis increased from 1.6:1 in 1965 to nearly 3:1 in 1985. After, the ratio decreased, reaching a nadir in 1994-95. The past decade has seen a sharp rise in syphilis cases among men, driven mostly by the MSM community. Males with primary and secondary syphilis outnumber females 10 to 1. Among women, the reported primary and secondary syphilis rate increased from 0.9 to 1.5 per 100,000 population per year during 2005- 2008 and decreased to 0.9 in 2013.
You face an increased risk of acquiring syphilis if you:
- Engage in unprotected sex
- Have sex with multiple partners
- Are a man who has sex with men
- Are infected with HIV, the virus that causes AIDS
- The cause of syphilis is a bacterium called Treponema pallidum. The most common route of transmission is through contact with an infected person’s sore during sexual activity. The bacteria enter your body through minor cuts or abrasions in your skin or mucous membranes. Syphilis is contagious during its primary and secondary stages, and sometimes in the early latent period.
- Less commonly, syphilis may spread through direct unprotected close contact with an active lesion (such as during kissing) or through an infected mother to her baby during pregnancy or childbirth (congenital syphilis).
- Syphilis can’t be spread by using the same toilet, bathtub, clothing or eating utensils, or from doorknobs, swimming pools or hot tubs.
- Once cured, syphilis doesn’t recur on its own. However, you can become re infected if you have contact with someone’s syphilis sore.
Stages of syphilis
Syphilis develops in stages, and symptoms vary with each stage. But the stages may overlap, and symptoms don’t always occur in the same order. You may be infected with syphilis and not notice any symptoms for years.
The first sign of syphilis is a small sore, called a chancre (SHANG-kur). The sore appears at the spot where the bacteria entered your body. While most people infected with syphilis develop only one chancre, some people develop several of them. The chancre usually develops about three weeks after exposure. Many people who have syphilis don’t notice the chancre because it’s usually painless, and it may be hidden within the vagina or rectum. The chancre will heal on its own within three to six weeks.
Within a few weeks of the original chancre healing, you may experience a rash that begins on your trunk but eventually covers your entire body even the palms of your hands and the soles of your feet. This rash is usually not itchy and may be accompanied by wart-like sores in the mouth or genital area. Some people also experience hair loss, muscle aches, a fever, sore throat and swollen lymph nodes. These signs and symptoms may disappear within a few weeks or repeatedly come and go for as long as a year.
If you aren’t treated for syphilis, the disease moves from the secondary to the latent (hidden) stage, when you have no symptoms. The latent stage can last for years. Signs and symptoms may never return, or the disease may progress to the tertiary (third) stage.
Tertiary (late) syphilis
About 15 to 30 percent of people infected with syphilis who don’t get treatment will develop complications known as tertiary (late) syphilis. In the late stages, the disease may damage your brain, nerves, eyes, heart, blood vessels, liver, bones and joints. These problems may occur many years after the original, untreated infection.
Babies born to women who have syphilis can become infected through the placenta or during birth. Most newborns with congenital syphilis have no symptoms, although some experience a rash on the palms of their hands and the soles of their feet. Later symptoms may include deafness, teeth deformities and saddle nose where the bridge of the nose collapses.
Without treatment, syphilis can lead to damage throughout your body. Syphilis also increases the risk of HIV infection and, for women, can cause problems during pregnancy. Treatment can help prevent future damage but can’t repair or reverse damage that’s already occurred.
Small bumps or tumors
Called gummas, these bumps can develop on your skin, bones, liver or any other organ in the late stage of syphilis. Gummas usually disappear after treatment with antibiotics.
Syphilis can cause a number of problems with your nervous system, including:
- Hearing loss
- Visual problems
- Loss of pain and temperature sensations
- Sexual dysfunction in men (impotence)
- Bladder incontinence
- Sudden, lightning-like pains
These may include bulging (aneurysm) and inflammation of the aorta your body’s major artery and of other blood vessels. Syphilis may also damage heart valves.
Adults with sexually transmitted syphilis or other genital ulcers have an estimated two- to fivefold increased risk of contracting HIV. A syphilis sore can bleed easily, providing an easy way for HIV to enter your bloodstream during sexual activity.
Pregnancy and childbirth complications
If you’re pregnant, you may pass syphilis to your unborn baby. Congenital syphilis greatly increases the risk of miscarriage, stillbirth or your newborn’s death within a few days after birth.
Diagnosis and test
A doctor will carry out a physical examination and ask about a patient’s sexual history before carrying clinical tests to confirm syphilis.
Blood tests: These can detect a current or past infection, as antibodies to the disease will be present for many years.
Bodily fluid: from a chancre during the primary or secondary stages can be evaluated for the disease.
Cerebrospinal fluid: may be collected through a spinal tap and examined to test for any impact on the nervous system.
If there is a diagnosis of syphilis, any sexual partners must be notified of and tested for the disease.
Local services are available to notify sexual partners of their potential exposure to syphilis, to enable testing and, if necessary, treatment.
Treatment and medications
- When diagnosed and treated in its early stages, syphilis is easy to cure. The preferred treatment at all stages is penicillin, an antibiotic medication that can kill the organism that causes syphilis. If you’re allergic to penicillin, your doctor will suggest another antibiotic.
- A single injection of penicillin can stop the disease from progressing if you’ve been infected for less than a year. If you’ve had syphilis for longer than a year, you may need additional doses.
- Penicillin is the only recommended treatment for pregnant women with syphilis. Women who are allergic to penicillin can undergo a desensitization process that may allow them to take penicillin. Even if you’re treated for syphilis during your pregnancy, your newborn child should also receive antibiotic treatment.
- The first day you receive treatment you may experience what’s known as the Jarisch-Herxheimer reaction. Signs and symptoms include a fever, chills, nausea, achy pain and headache. This reaction usually doesn’t last more than one day.
After you’re treated for syphilis, your doctor will ask you to:
- Have periodic blood tests and exams to make sure you’re responding to the usual dosage of penicillin
- Avoid sexual contact until the treatment is completed and blood tests indicate the infection has been cured
- Notify your sex partners so that they can be tested and get treatment if necessary
- Be tested for HIV infection
Preventive measures that can decrease the risk of contracting syphilis, include:
- Abstinence from sex
- Long-term mutual monogamy with an uninfected partner
- Condom use, although these protect only against genital sores and not those on the body
- Use of a dental dam, or plastic square, during oral sex
- Not sharing sex toys
- Avoiding alcohol and drugs that could potentially lead to unsafe sexual practices
Having syphilis once does not mean a person is protected from it. Once it is cured, it is possible to contract it again.