People get syphilis by having sex with someone who has syphilis.
If a person does not get treatment they will get rashes, sores, fever, or feel like they have the flu. Sometimes people lose some of their hair, eyebrows, and eyelashes. Later, people who don't get cured get syphilis in the brain, heart, or other parts of their body. A female who is pregnant can give syphilis to her baby before it is born, or during birth. A sore that usually does not hurt on the penis, scrotum, lip, rectum, nipple, outside the female's vagina, or inside the vagina.