What is Syphilis and how is it transmitted? Read on to find out more about one of the most common sexually transmitted infections (STI).

Syphilis is a Sexually Transmitted Infection (STI) caused by a bacterium. The infection may not cause alarm initially as the sore is usually painless. However, if left untreated, the infection can affect other organs in the body such as the heart and brain. It is important that the infection is diagnosed early and treated with antibiotics.

Syphilis Causes and Risk Factors

Syphilis is a bacterial infection caused by Treponema pallidum. The infection is almost always transmitted through sexual contact with an infected person. It is spread from person to person through direct contact with a syphilis sore (ulcer). Sores are found mainly on the external genitals such as the vagina, and/or on the anus, rectum, lips, and in the mouth. It also can pass through broken skin on other parts of the body.

In addition, a pregnant woman with syphilis can pass the infection to her baby who may develop mental and physical problems as a result.

Syphilis cannot be spread through contact with toilet seats, swimming pools, bathtubs, shared clothing, or eating utensils.

Signs and Symptoms of Syphilis

Many people infected with syphilis may not realise they have the disease and remain untreated for years because they do not have any symptoms. Hence, they remain at risk for late complications.

Signs and symptoms of syphilis vary depending on the stage of infection. There are four stages in syphilis:

Primary Stage

The first symptom, which is usually a single sore (called chancre), occurs about three weeks from the time the person was exposed to the bacterium. The start of the first symptom can range from 10 to 90 days. The chancre is described as a painless, firm, and small sore and is usually the spot where the bacterium entered the body. The sore lasts three to six weeks and heals without treatment.

Secondary Stage

The secondary stage is characterised with the appearance of a rash on one or more areas of the body including the palms and the soles. The rash appears rough and is reddish brown in colour. Sometimes, the person who has syphilis may not notice that he is in the secondary stage of the disease as the rashes are so faint. The rashes may also resemble other rashes caused by other diseases. 

Other symptoms of secondary syphilis may include fever, swollen lymph glands, sore throat, patchy hair loss, headaches, weight loss, muscle aches and fatigue.

The signs and symptoms of secondary syphilis will resolve with or without treatment. People who are left untreated at this stage will go into the latent stage of infection, which may put them at risk of serious complications.

Late and Latent Stages

The latent stage of syphilis is the hidden stage as the infected person does not exhibit any signs and symptoms. However, the infection remains in the body and can last for years.

In the late stages of syphilis, the disease may have damaged vital organs of the body such as the heart, blood vessels, brain, nerves, eyes, liver, bones, and joints. Complications of syphilis may occur, leading to serious consequences, even death.

Complications of Syphilis

Without treatment, syphilis can lead to complications for your body. It may increase your risk of HIV infection because of the existence of open sores. If you are pregnant, syphilis can affect the baby in your womb. There is also a higher chance of premature birth.

Complications include:
 • Small bumps called gummas which can develop on your skin, bones, liver, or any other organ. 
 • Heart problems which include aortic aneurysm (bulging of the aorta, a major artery) and valvular heart disease (cardiovascular disease process involving one or more of the four valves of the heart).
 • Nerve problems such as stroke, meningitis (inflammation of the membranes and fluid surrounding the brain and spinal cord), poor muscle coordination, numbness, deafness, visual problems, personality changes, and dementia.

Screening and Diagnosis

Syphilis infection is suspected if a painless sore is found on a person’s genital organs. A swab from the infected sore is done and if bacteria are present, they will show up when examined using a special microscope called a dark-field microscope.

A blood test is another way to diagnose a person infected with syphilis. The blood test will detect and measure the antibodies against the syphilis bacteria.


Syphilis is treated with antibiotics. It is easy to treat syphilis when the infection is in its early stages. Penicillin, which is the antibiotic for syphilis, is given intramuscularly (injected into a muscle). People who are allergic to penicillin are given other types of antibiotics for treatment. Treatment will kill the syphilis bacterium and prevent further damage, but it will not repair any damage that is already done.

It is important that a person with risky sexual behaviour goes for syphilis screening on a regular basis as effective treatment is available and severe complications can be avoided.

A person who receives syphilis treatment must abstain from sexual contact with new partners until the syphilis sores are completely healed. They should also inform their sex partners about the infection so that they can also be tested for syphilis and receive treatment if necessary.


As with any other STI, the best way to prevent syphilis is to abstain from having sex or to keep a mutual relationship with a single partner who has been tested and is not infected. However, for people who decide to have sex, it's important to use protection (such as latex condoms) correctly and consistently. However, if there are any sores that cannot be covered by the condom, it is best not to engage in any sexual activity until the sores are healed.

Remember, the transmission of syphilis cannot be prevented by washing the genitals, urinating, and/or douching after sex.

It is important that sex partners talk openly if they have had STI in the past (including their HIV status) so that preventive action can be taken.

If you develop any unusual discharge, sores, or rashes, particularly on your genitals, refrain from sex and see your doctor immediately for treatment.

If you think you may have an STI, go for a sexual health screening or HIV screening. You can get yourself tested for STIs or HIV/AIDS at polyclinics, private clinics, and hospitals.

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