Overview
Syphilis is an infection caused by bacteria. It is most often transmitted through sexual contact. The disease begins with a sore on the genitals, rectum, or mouth, which is usually painless. Syphilis is transmitted from person to person through direct contact with these sores. It can also be transmitted to a baby during pregnancy or childbirth, and sometimes through breastfeeding.

After infection, the syphilis bacteria can remain in the body for many years without causing symptoms. However, it can reactivate. Without treatment, syphilis can cause damage to the heart, brain, and other organs. It can be fatal.

Early syphilis can be cured, sometimes with a single injection of an antibiotic called penicillin. Therefore, it is essential to get medical checkups as soon as any symptoms of this disease are detected. All pregnant people should be tested for syphilis at their first prenatal checkup.

Symptoms

Syphilis develops in stages. Symptoms can vary with each stage, although the stages may overlap and symptoms may not always appear in the same order. You can be infected with the syphilis bacteria without noticing any symptoms for years.

Primary Syphilis
The first symptom of syphilis is a small sore, called a chancre. It is usually not painful. It appears where the bacteria entered the body. Most people with syphilis develop only one chancre. However, some people have more than one.

A chancre usually forms about three weeks after contact with the syphilis bacteria. Many people with syphilis don't notice it. This is because it is often painless. It can also be hidden in the vagina or rectum. The chancre will heal on its own within 3 to 6 weeks.

Secondary syphilis
When the first chancre heals, or a few weeks after it heals, you may have a rash.

These are the characteristics of the rash caused by syphilis:

It is most often not itchy.
It may have a rough, reddish, or brownish appearance.
It may be so subtle that you can barely see it.
It often starts on the trunk, including the chest, stomach, pelvis, and back. Over time, it may also appear on the extremities, palms, and soles of the feet.

Along with the rash, other symptoms may appear:

Wart-like sores in the mouth or genital area
Hair loss
Muscle aches
Fever
Sore throat
Tiredness, also known as fatigue
Weight loss
Swollen lymph nodes
Symptoms of secondary syphilis may go away on their own. However, without treatment, they may return and continue for months or years.

Latent syphilis
If you don't receive treatment for syphilis, the disease progresses from the secondary stage to the latent stage. This is also called the hidden stage because you don't have symptoms. The latent stage can last for years. Symptoms may never appear again. However, without treatment, the disease could lead to major health problems (complications).

Tertiary Syphilis
After the latent stage, about 30% to 40% of people with syphilis who do not receive treatment experience complications. This stage is known as tertiary syphilis. It is also called late syphilis.

The disease can cause damage to the following areas:

Brain
Nerves
Eyes
Heart
Blood vessels
Liver
Bones and joints
These problems can occur many years after the original, untreated infection.

Syphilis Transmission
If syphilis is not treated at any stage, it can affect the brain, spinal cord, eyes, and other parts of the body. This can cause life-threatening health problems.

Congenital Syphilis
Pregnant women with syphilis can pass the disease to their babies. Babies can be infected before birth through the placenta, the organ that provides nutrients and oxygen in the uterus. Infections can also occur during delivery.

Newborns with congenital syphilis usually have no symptoms, but if not treated promptly, some may develop the following symptoms:

Skin sores and rashes
Fever
A type of discoloration of the skin and eyes (jaundice)
Low levels of red blood cells (anemia)
Swollen spleen and liver
Sneezing or a stuffy and runny nose (rhinitis)
Bone changes
Later-onset symptoms may include deafness, dental problems, and saddle nose, a condition in which the nasal septum collapses.

Babies with syphilis can be born prematurely. They can also die in the womb before birth or after birth.

When to see a doctor
Call a member of the healthcare team if you or your child have symptoms of syphilis. This may include an unusual discharge, a sore, or a rash, especially in the groin area.

You should also be tested for syphilis if:

You have had sexual contact with someone who might have the disease.
If you have another sexually transmitted infection, such as HIV.
You are pregnant.
If you have frequent sex with more than one partner.
If you have unprotected sex, that is, without using a condom.

Causes
Syphilis is caused by a bacterium called Treponema pallidum. The most common way syphilis is transmitted is through contact with an infected person's sore during vaginal, oral, or anal sex.

The bacteria enter the body through small cuts or scrapes in the skin, or through moist internal surfaces of some parts of the body.

Syphilis is contagious during its primary and secondary stages. Sometimes, it is also contagious during its latent stage, which occurs within a year of infection.

In less common cases, syphilis can be spread through kissing or contact of an active sore with the lips, tongue, mouth, breasts, or genitals. It can also be transmitted to a baby during pregnancy or childbirth, and sometimes during breastfeeding.

Syphilis cannot be spread by casual contact with objects that have been touched by an infected person.

You cannot catch syphilis by using a toilet, bathtub, clothing, eating utensils, doorknobs, swimming pools, or hot tubs.

Once cured, syphilis does not recur on its own. However, you can become infected again if you come into contact with someone else's syphilis sore.

Risk factors
The risk of contracting syphilis is higher in the following cases:

Having unprotected sex.
Having sex with more than one partner.
Living with HIV, the virus that causes AIDS if left untreated.
The chances of contracting syphilis are higher in men who have sex with other men. The higher risk may be partly related to the fact that this group has less access to medical care and uses condoms less. Another risk factor for people in this group is having recently had sex with people they met through social media apps.

Complications
Without treatment, syphilis can lead to damage throughout the body. Syphilis also increases the risk of HIV infection and can cause problems during pregnancy. Treatment helps prevent damage, but it cannot repair or reverse damage that has already occurred.

Small lumps or masses.
Only rarely, in the advanced stage of syphilis, bumps (syphilitic gumma) may appear on the skin, bones, liver, or other organs. Most go away after treatment with medications and antibiotics.

Neurological problems
Syphilis can cause many problems in the brain, around the brain, or in the spinal cord. These problems include:

Headache.
Stroke.
Meningitis, a disease in which the protective layers of tissue surrounding the brain and spinal cord become inflamed.
Confusion, personality changes, or trouble concentrating.
Dementia-like symptoms, such as loss of memory, judgment, and decision-making.
Inability to move certain parts of the body, called paralysis.
Trouble getting or maintaining an erection, called erectile dysfunction.
Bladder problems.