Microbiology

Syphilis is a sexually transmitted infection (STI) that can cause serious health problems without treatment. It develops in four stages: primary, secondary, latent, and tertiary.

1. In the primary stage, painless sores called chancres appear at the site of infection (mouth, anus, rectum, vagina, or penis). The sores heal on their own after 3 to 6 weeks, but you can still spread syphilis.

2. In the secondary stage, symptoms include a rough red or reddish-brown rash on the palms of hands and soles of feet, swollen lymph nodes, fever, sore throat, patchy hair loss, headaches, and body aches, and extreme tiredness (fatigue). These symptoms will go away even if you don’t get treated. But if you’re not treated, your infection will get worse.

3. During the latent stage, the syphilis bacteria are still alive in your body, but you have no signs or symptoms of the infection. You’re not contagious during this stage, but syphilis may still affect your heart, brain, nerves, bones, and other parts of your body. This phase can last for years.

4. The tertiary (late) stage begins when symptoms from the secondary stage disappear. Syphilis isn’t contagious at this point, but the infection has started to affect your organs. This can lead to death. Symptoms of tertiary syphilis may include problems controlling muscle movements, numbness, vision problems (you may start going blind), and dementia.