Skip to main content


Treponema pallidumSyphilis is a sexually transmitted infection that is caused by the bacterium Treponema pallidum. Syphilis infection occurs in stages with each stage associated with different symptoms. Syphilis alternates between times when it is active and inactive (latent). Antibiotic treatment can cure syphilis, although it will not undo the damage caused by later stage syphilis.



For more information on symptoms, causes, treatments and prevention see the Overview section.

Information for Health Professionals

Syphilis is a sexually transmitted infection (STI) that, when left untreated, can progress to a late stage that causes serious health problems. The infection alternates with periods of being active and inactive (latent). When the infection is active, symptoms occur. But when the infection is latent, no symptoms appear even though you still have syphilis.

Syphilis is known as the great imitator since it appears to be like many other diseases and is difficult to diagnose.


Symptoms of syphilis may not be noticed or may mimic those of many other diseases. This may cause an infected person to delay seeking medical care and can make diagnosis difficult.

The four stages of syphilis have different symptoms. 

Primary stage: During this stage of syphilis, a painless open sore (chancre) develops. Because syphilis is usually passed through sexual activity, sores are often found in the genital area, anus, or mouth, but they may also be found wherever the bacteria entered the body. This stage usually begins 3 – 4 weeks after the initial infection though may be as early as 9 days. 

Secondary stage: A skin rash and other symptoms occur during the secondary stage, which begins 4 to 10 weeks after the initial infection. Secondary syphilis is highly contagious through direct contact with the mucous membranes or rash to the genital area. 

Latent stage : This stage is often called the hidden stage of syphilis because usually no symptoms are present. The latent stage is defined as the year after a person becomes infected. A person in early latent stage may still be contagious. Many times, latent-stage syphilis is detected in a mother only after she gives birth to a child infected with syphilis (congenital syphilis). 

Late (tertiary) stage: If syphilis is not detected and treated in the early stages, problems can develop because of damage caused by having the syphilis bacteria in the body for so many years. These may include heart disorders, mental disorders, blindness, other problems associated with the nervous system, and even death.


Syphilis is caused by a type of bacterium (Treponema pallidum) that usually enters the body through the mucous membranes. An infected person can pass the disease to others (is contagious) whenever a sore or a rash is present. 

Anyone who comes into close skin-to-skin contact with a syphilis sore can develop syphilis. You don't have to have sexual intercourse to get syphilis — exposure can result from close contact with an infected person's genitals, mouth, or rectum if a sore is present.


If not treated, syphilis may linger and may progress to the late stage where more serious health problems, such as blindness, heart disorders, mental disorders, nervous system problems, and even death.


The first steps in diagnosing syphilis are discussing the history of your symptoms and sexual activities with a health professional and having a physical examination. 

The diagnosis of syphilis is usually confirmed with one of several blood tests. If sores are present, a health professional may examine the fluid from one of the sores with a microscope to see whether syphilis bacteria are present.


Treatment is needed to cure a syphilis infection, prevent complications, and prevent the spread of the infection to others. It is critical to treat a pregnant woman who has syphilis — without treatment, syphilis can cause a miscarriage or stillbirth, or cause a baby to be born with the disease (congenital syphilis). 

If detected, syphilis can be cured with antibiotics. Antibiotic treatment cannot reverse the damage caused by the complications of late-stage syphilis, but it can prevent further complications. 

A special type of penicillin is the preferred drug for treating syphilis. If you are allergic to penicillin, it is very important to tell your doctor. Your doctor will still be able to treat the syphilis but will consult with a specialist on the best antibiotic choice. 

You will need follow-up blood tests to make sure that the antibiotic treatment has been effective. Any partners, male or female, that you have had sex with will also need to be examined, tested and treated for syphilis.


You can reduce your risk of spreading or becoming infected with syphilis by practicing safe sex.

  • Use condoms.
  • Avoid sexual contact if you have symptoms of an STI or are being treated for an STI.
  • Avoid sexual contact with anyone who has symptoms of an STI or who may have been exposed to an STI.
  • Your risk for an STI increases if you have several sex partners.
  • Make sure you are tested for syphilis if you are pregnant or if you think have been at risk for syphilis.
SOURCE: Syphilis ( )
Page printed: . Unofficial document if printed. Please refer to SOURCE for latest information.

Copyright © BC Centre for Disease Control. All Rights Reserved.

    Copyright © 2019 Provincial Health Services Authority.