What is syphilis?


Syphilis: Overview

Syphilis is an infection caused by bacteria. It's usually spread through sex. It's a type of sexually transmitted infection (STI).

The first symptom is usually a painless, red sore on the genitals, rectal area, or mouth. This is called a chancre (say "SHANK-er"). Later symptoms include a rash, a fever, and swollen lymph nodes. Your hair may start to fall out. Or you may feel like you have the flu.

Sometimes these symptoms go away on their own. But this doesn't mean that the infection is gone. If you don't treat syphilis with antibiotics, the infection can spread in your body. You can also spread it to others.

Antibiotics can cure syphilis and prevent more serious problems caused by it. You and your sex partner or partners need antibiotic treatment. This is to prevent passing the infection back and forth or to others.


Syphilis is an infection spread through sex. The most common symptom is a painless sore on the genitals, rectal area, or mouth. Later symptoms may include rash, hair loss, and flu-like symptoms.

Early symptoms may go away on their own, but the infection is still there and can spread if it isn't treated. Antibiotics can treat syphilis and help prevent serious health problems, like problems with the heart or brain.

What happens when you have syphilis?

The main symptom of the first stage of syphilis is an open sore. A rash and other symptoms occur during the second stage. That’s followed by a time without symptoms. Syphilis can move to the late (tertiary) stage, causing serious problems. Antibiotics can’t undo damage, but they can cure syphilis at any stage.

What are the symptoms of syphilis?

One of the first signs of syphilis is an open sore that appears wherever the bacteria entered the body. As syphilis spreads, a person may get a skin rash and have other symptoms like a fever, swollen lymph nodes, and weight loss. Without treatment, syphilis may cause blindness and nerve and heart problems.

How is syphilis treated?

At any stage of 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. You and any sex partners that you may have exposed to the infection will need to be treated.

How is syphilis diagnosed?

Your doctor will do a physical exam and ask about your symptoms and sexual history. You'll probably have one or more blood tests, especially if you don't have sores. If you do have sores, your doctor may test the fluid from one of the sores to check for syphilis bacteria.

How can you care for yourself when you have syphilis?

  • Get all the recommended shots. Your doctor probably gave you an antibiotic shot. If you've had syphilis for a while, you may need 2 more shots.
  • If your doctor prescribed antibiotic pills, take them as directed. Do not stop taking them just because you feel better. You need to take the full course of antibiotics.
  • Don't have sexual contact with anyone while you're being treated. Wait at least 7 days after you and your partner or partners are treated and until all sores are healed before you have sexual contact. Even if you use a condom, you and your partner or partners can still spread the infection.
  • Wash your hands if you touch an infected area. This helps prevent spreading the infection to other parts of your body or to other people.
  • Tell your sex partner or partners that you have syphilis. They'll need treatment even if they don't have symptoms.
  • Go to all follow-up tests. This helps your doctor check that treatment worked. Your doctor will tell you when to have testing done.

How does syphilis spread?

An infected person who has a sore or a rash can pass syphilis to others. It's usually spread during vaginal, anal, and oral sex. But it can be spread by any close contact with the genitals, mouth, or rectum of an infected person. If you're infected while you're pregnant, you can pass syphilis to your baby.

What causes syphilis?

Syphilis is caused by a type of bacteria. The bacteria are usually spread through sexual contact. They most often enter the body through the tissues that line the throat, nose, rectum, penis, or vagina.

What is syphilis?

Syphilis is a sexually transmitted infection (STI) caused by a type of bacteria. 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. But you still have syphilis.

You can get syphilis without having sexual intercourse. Just being in close contact with an infected person's genitals, mouth, or rectum is enough to expose you to the infection.

What are the stages of syphilis?

Syphilis develops in four stages. Each stage has a different set of symptoms.

Primary stage

During the primary stage of syphilis, one or more sores (chancres) form at the site where the bacteria entered the body. This often occurs within 3 weeks of exposure but can range from 10 to 90 days. A person is highly contagious during the primary stage and can easily pass the infection to others.

  • A chancre often appears in the genital area. But sores may also occur in or near the anus or in or near the mouth. The sores are usually painless, so they may go unnoticed if they're inside the vagina or the rectum.
  • Swelling of the lymph nodes may occur near the area of the chancre.
  • The chancre usually lasts for 3 to 6 weeks. It heals without treatment and may leave a thin scar. But even though the chancre has healed, the person still has syphilis. They can still pass the infection to others.

Secondary stage

During secondary syphilis, a person is highly contagious. A rash appears 2 to 12 weeks after the chancre develops and sometimes before it heals. The rash often forms over the body, often on 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 than 2 cm (0.8 in.) across. But the rash may look like other more common skin problems.
  • There may be small, open sores on mucous membranes. The sores may contain pus. Or there may be moist sores that look like warts (called condyloma lata).
  • In people who have dark skin, the sores may be a lighter color than the skin around them.

The skin rash usually heals within 2 months on its own without scarring. After the rash heals, the skin may be discolored. But even though the skin rash has healed, the person still has syphilis and can still pass it to others.

Other symptoms may also occur. This means that the infection 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. These can include neck stiffness, headaches, grouchiness, paralysis, unequal reflexes, and irregular pupils.

Latent (hidden) stage

Without treatment, an infected person will progress to the latent (hidden) stage. During this stage, the bacteria that cause syphilis stay in the body without causing symptoms. This time with no symptoms usually happens after the secondary-stage rash goes away. But the latent stage can also happen between the primary and secondary stage. It 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.

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

When relapses no longer occur, a person isn't contagious through contact. But those who are pregnant may still pass the infection to their baby. They may have a miscarriage or a stillbirth. Or their baby may be born infected (congenital syphilis).

Tertiary (late) stage

This is the most destructive stage of syphilis. If a person doesn't get treatment, this stage may start as early as 1 year after infection or at any time during the person's lifetime. A person with syphilis may never have 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. They may include:

  • Gummata. These are large sores inside the body or on the skin.
  • Cardiovascular syphilis. This affects the heart and blood vessels.
  • Neurosyphilis. This affects the nervous system.

Syphilis: When to call

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You do not get better as expected.
  • Your symptoms continue or come back after treatment.
  • You develop new symptoms, such as a fever.

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