Syphilis and Men-who-have-Sex-with-Men (MSM)

Syphilis and Men-who-have-Sex-with-Men (MSM)

What is syphilis?

Syphilis is a sexually transmitted infection caused by a type of bacteria called Treponema Pallidum. It is a curable infection, however, if left undiagnosed or untreated, can lead to very serious health complications and even mortality. Syphilis can affect both men and women equally.

Who is most at risk for syphilis?

Men who have sex with men (MSM) have at least 25 times more risk of contracting syphilis compared to heterosexual men, people who are HIV positive, sex workers and clients of sex workers.

How does syphilis get transmitted?

The most common route of transmission is through sexual intercourse, by direct skin or mucous membrane contact with the syphilitic ulcer (called chancre). Chancres can be found anywhere in the body, but commonly occur inside the mouth, anus or genitals. So, syphilis can be transmitted from any type of sexual intercourse including oral sex and non penetrative sex. If a pregnant woman gets infected with syphilis, this can also cause adverse effects to the baby. However, it is important to know that infection is still possible when the infected person has no symptoms.

Syphilis can also be passed on from blood transfusion and sharing of needles with an infected person.

What are the symptoms of syphilis?

Often people infected with syphilis have no symptoms at all. When the symptoms are present, they vary with the stage of the disease


Infectious Syphilis

Primary syphilis

A painless ulcer (chancre) inside the mouth or on the genitals can occur as early as 10 days post exposure, while some may take up to 90 days post exp to appear. Some people may not realize it because it is painless. After 2-6 weeks, the chancre heals up. If left untreated, the infection remains in the body

Secondary syphilis

When primary syphilis is not treated, infection enters the blood stream and spreads to other part of the body, this is known as secondary syphilis. If symptoms occur, they typically appear as a rash over the body, palms, soles, or flu like illness (fever, muscle ache, swollen lymph nodes and sore throat). Some may notice patchy hair loss, lesions inside mouth, genital and anus. These symptoms will appear 2 to 6 months after catching the infection and they can last several months. Symptoms may go unnoticed and even disappear on their own but infection still remains if untreated.

Early latent syphilis

This condition means the person caught the infection less than 1 year’s duration without any symptoms.

Non infectious Syphilis

After 1 year, syphilis is usually no longer infectious to sexual partners

Late latent syphilis

When last risky exposure is more than 1 year, with no symptoms and no obvious damage to body but a positive syphilis antibody is detected, the person can be assumed to have late latent syphilis.

If untreated, this stage can last many years or life long and may lead to development of tertiary syphilis.

Tertiary syphilis

This stage occurs 10-30 years after catching the infection and can cause complications to the eyes, brain, nerves, spinal cord, blood vessels, skin, and heart, which may lead to disability or death.

How do I get tested?

We provide rapid syphilis antibody screening test, which requires only a finger prick and results will be available in 15 minutes.

As there may be a window period of 3 months after you catch syphilis for the antibodies to be detectable, you are encouraged to repeat the test at the 3rd month if you think you had a risky exposure.

Is syphilis treatable?

Syphilis is treatable with penicillin injection or oral antibiotics if you have penicillin allergy. The number of injections needed depends on the stage of the syphilis infection and HIV status.

It is important that sexual partners get tested and treated to prevent infection developing in them and reinfecting you.

Once syphilis is treated adequately and appropriately, it is no longer infectious. You will be followed up with regular blood test for 2 years to confirm the infection is cured.

For men who have sex with men, it is important to have STI/HIV screen at least once a year, even for protected exposures with condom. It is also recommended to get Hepatitis A/B vaccinations as well as HPV vaccination (GARDASIL) to protect against development of anal cancers and genital warts.


Need more advice?

Come down to Our Clinics for a discussion with Our Doctors, or call our clinics for more information:

Singapore Branches


Where to find us – here

Selected clinics are open on Saturday and Sunday.


All Our Doctors are Fully Certified and Trained to conduct specialised STD Screening,  STD Testing & STD Treatment and HIV Testing.

For lady patients who prefer female doctors, we have professional certified female Doctors to attend to your medical needs.




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