Syphilis is an STD with different stages. There are different signs and symptoms associated with each stage. The signs can be mild, and you might not notice.
Primary syphilis: A painless sore (or sores) called a chancre appears on, around, or inside the penis, vagina, mouth, or anus. The chancre appears 10-90 days after exposure, and generally last 2-5 weeks. The sore can disappear on its own without treatment. It is highly contagious in this stage.
Secondary Syphilis: A few weeks after the chancre disappears, a rash may appear on your body, palms of your hands, and soles of your feet.
Toward the last stage, there may be times when your syphilis infection is latent (there are no signs or symptoms at all) for months or even years. Symptoms usually disappear on their own and you are less likely to transmit to your sexual partner(s). However, the disease is still in your body and can cause serious complications.