About syphilis

Syphilis is a bacterial STI that affects many organs / systems of the body.

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What is it?

Syphilis is a bacterial sexually transmitted infection (STI) that affects many organs / systems of the body. It is usually transmitted during unprotected vaginal, oral, or anal sex. It can also be passed on from direct contact with your partner’s genitals, even if there is no ejaculation. Infected mothers can pass syphilis to their unborn child or baby during labor, and this can cause catastrophic consequences, therefore most pregnant women are offered a syphilis screening test early on in pregnancy.

How is it spread?

The infection is typically spread through unprotected (without a condom) vaginal, oral, or anal sex. It can also be passed on through contact with an infected partner’s genitals, even without ejaculation or orgasm. It can also be spread through the sharing of sex toys, particularly if not washed before each person uses them or if not covered with a condom.

Syphilis can be spread from a mother with syphilis to her unborn baby.

Syphilis is not spread through casual contact with objects such as toilet seats, swimming pools, or sharing clothing or eating utensils. You cannot get it from masturbating by yourself.


Syphilis often does not cause any symptoms at all and is commonly only picked up from a blood test. If a person does develop symptoms these depend on the stage, as there are several stages of syphilitic infection. In between these stages the person remains symptom free.

How does it affect you?

Primary syphilis: a red lump or firm ulcer (chancre) appears at the site where syphilis enters your body (penis, vagina, or anus, or in the rectum, lips, or in the mouth) Because the sore is painless, it can easily go unnoticed. This chancre appears within three months of becoming infected, is highly infectious, and can be accompanied by swelling of local lymph glands. It resolves by itself, without treatment after 3 to 6 weeks.

Secondary syphilis commonly causes a general body rash, lymph gland swelling in the neck, groin or armpits, a flu like illness, fevers, patchy alopecia (hair loss), sore throat, headaches, weight loss, muscle aches, tiredness, and mucous membrane lesions (superficial sores in your mouth, vagina, or anus). The spotty rash is red, or reddish brown and usually appears on your trunk, the palms of your hands and/or soles of your feet. Less commonly you can develop meningitis, hearing loss or eye involvement. These often appear within the first 6 months of infection.

The signs and symptoms of primary and secondary syphilis can be mild, and they might not be noticed. Without the right treatment, your infection will move to the latent and possibly tertiary stages of syphilis.

Latent stage is usually a period where the infected person has no symptoms or signs, often for many years. Most people with untreated syphilis do not develop tertiary syphilis.

Tertiary syphilis, if it develops, is the most serious stage of syphilis and can occur many years after infection (10-30 yrs.). It can affect many different organ systems: heart and blood vessels, bones, skin, brain, and nervous system (paralysis, dementia) and the results may be life threatening.


Syphilis can be identified from a simple blood test. In those with ulcers or mucous membrane lesions, a swab can be taken that can allow the organism to be seen under the microscope, there and then (allowing treatment to be given immediately), or a highly sensitive swab can be sent off to the laboratory. It can take up to three months after infection for a blood test to become positive so if you test within three months, and the test is negative, it is advisable to return for a repeat test later if you think you have been at risk.

When should I take a test?

You should get tested if you have any of the symptoms or effects from the primary, secondary, or latent stages, including:

  • Small, painless sore (chancre) on the genitals, or in the mouth, anus, or rectum.
  • Rough, red rash, usually on the palms of the hands or the bottom of the feet.
  • Fever.
  • Headache or muscle aches.
  • Sore throat.
  • Swollen glands.
  • Fatigue.
  • Weight loss.
  • Hair loss in patches.

Regardless of symptoms, you should get tested regularly if you have a high risk of getting syphilis. Those at greater risk of getting syphilis include people who have:

  • Multiple sex partners.
  • A partner with multiple sex partners.
  • Unprotected sex (sex without using a condom).
  • An HIV infection and are sexually active.
  • Another sexually transmitted disease, such as gonorrhea.
  • Sex with men who have sex with men (MSM).


Find out more about the results you can get for syphilis.

Treatment is straightforward and involves an injection of penicillin or a course of antibiotic tablets. The length of treatment depends on the stage of infection.

Previous successful treatment for syphilis doesn't make you immune to catching the infection again but, some screening tests will always remain positive, and you may have to undergo a different syphilis test to see if you have become re-infected or if the initial infection has been inadequately treated. 

Contacting partners

If you are diagnosed with syphilis you will need to inform previous sexual partners as they may also be infected. How far back you go in contacting previous partners (look back period) depends on the stage of infection and your last negative syphilis test result (if you have ever had one). Your sexual health clinic doctor/nurse will advise you accordingly. Partners should be advised to get a syphilis test.

After treatment

You should have follow up syphilis blood tests to check that the infection has been treated appropriately.


You should not have oral, anal, or vaginal sex for a certain period of time after you have started treatment (your clinic will advise you accordingly) and until your current partner completes their treatment and until both you and your partner’s symptoms have abated. This is to avoid being re-infected and requiring further treatment.

If you have been infected with syphilis it is possible you may also have been infected with another STI. Therefore, it is advisable that you have a full sexual health screen for gonorrhea, chlamydia, LGV, hepatitis B and C, and HIV. We advise you to have another STI screen three months later because there is a higher risk of becoming infected with an STI (e.g., HIV) over the next year.

Use condoms as they help prevent transmission of syphilis by preventing contact with a sore. Be aware that infectious sores occur in areas not covered by a condom and transmission can therefore still take place. Encourage every partner to test for STIs.

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