Not every sexually transmitted infection causes obvious symptoms. Syphilis is one of the most deceptive, often progressing silently or presenting with signs that resemble other common illnesses. This is why it has earned the nickname "the great imitator."
Without treatment, the infection can remain hidden for years before causing serious complications involving the heart, brain, eyes, nervous system, and other vital organs.
The good news? Syphilis is highly treatable, especially when diagnosed early.
What causes syphilis?
Syphilis is caused by the bacterium Treponema pallidum and is most commonly spread through vaginal, anal, or oral sexual contact with an infected person. It can also be passed from a pregnant mother to her baby during pregnancy, making early screening especially important.
The bacteria survive poorly outside the human body, so transmission through everyday contact or shared objects is extremely unlikely.
Why is syphilis called the “Great Imitator”?
One of the biggest challenges with syphilis is that its symptoms can vary greatly—or may not appear at all.
Primary Stage
The first sign is usually a small, painless sore (chancre) that appears where the bacteria entered the body, commonly on the genitals, anus, or mouth.
Because the sore is often painless and heals on its own within a few weeks, many people mistakenly believe the infection has gone away.
Secondary Stage
Without treatment, the infection spreads through the bloodstream and may cause:
- A rash, often affecting the palms of the hands and soles of the feet
- Fever
- Swollen lymph nodes
- Fatigue
- Muscle aches
- Patchy hair loss
- Mouth or genital sores
These symptoms may also disappear without treatment, but the infection remains in the body.
Latent Stage
This is often called the "silent stage." There may be no symptoms at all, yet the infection continues to persist and can only be detected through blood tests.
Late (Tertiary) Syphilis
Years—even decades—after the initial infection, untreated syphilis can cause permanent damage to multiple organs, including:
- The heart and major blood vessels
- The brain and nervous system
- Bones and joints
- Eyes and hearing
Although these complications are uncommon today due to effective treatment, they remain a serious risk if syphilis is left untreated.
Can syphilis affect the brain? Yes.
Syphilis can involve the brain, spinal cord, eyes, or ears at any stage of the infection. This may lead to:
- Vision changes or blindness
- Hearing loss
- Persistent headaches
- Difficulty walking
- Memory problems
- Changes in behaviour or personality
Early diagnosis is essential to prevent these potentially irreversible complications.
How is syphilis diagnosed?
If syphilis is suspected, your doctor will take a medical history, perform an examination, and recommend appropriate laboratory testing.
Diagnosis typically involves:
- Blood tests to detect antibodies against the bacteria
- Examination of sores when present
- Additional investigations if there is concern that the infection has affected the brain or nervous system
Regular STI screening is recommended for individuals at increased risk, even if they have no symptoms.
Can syphilis be treated? Yes.
Penicillin remains the gold standard treatment for syphilis and continues to be highly effective across all stages of the disease.
The treatment depends on how long the infection has been present:
- Early syphilis often requires only one injection.
- Later stages may require multiple weekly injections.
- Infection involving the brain or nervous system requires intravenous treatment in hospital.
Some patients may experience a temporary flu-like reaction within the first 24 hours after treatment, known as the Jarisch-Herxheimer reaction. Although uncomfortable, this is a normal response to treatment and is not an allergic reaction to penicillin.
When should you consider getting tested?
You should speak with a healthcare professional if you:
- Notice a painless sore on the genitals, mouth, or anus
- Develop an unexplained rash, particularly on the palms or soles
- Have had unprotected sexual contact
- Have been informed that a sexual partner has syphilis
- Are pregnant or planning a pregnancy
- Would like routine STI screening for peace of mind
Early Detection Makes All the Difference
Syphilis is one of the few sexually transmitted infections that can be completely cured with timely treatment. Unfortunately, because symptoms are often mild or disappear on their own, many people delay seeking medical advice until complications develop.
At Raffles Medical, our experienced doctors provide confidential consultations, comprehensive STI screening, accurate diagnosis, and evidence-based treatment in a professional and supportive environment.
If you have concerns about your sexual health or believe you may have been exposed to syphilis, don't wait for symptoms to appear. Early testing and treatment can protect both your health and the health of your partner.
