The exact time of onset of syphilis varies from person to person and, in general, symptoms may appear after 2-4 weeks of unclean sexual intercourse. Syphilis is a sexually transmitted disease caused by infection with the syphilis spirochete. The syphilis spirochete first passes through the broken skin and enters the mucosal area within the skin and then gradually enters the bloodstream, a process that takes about 2-4 weeks. After 2-4 weeks, the patient may develop a hard chancre at the site of contact, which contains a large number of syphilis spirochetes. After 6-8 weeks, a blood test may detect antibodies to the syphilis spirochete. The diagnosis of syphilis is confirmed when the syphilis spirochetes enter the body to multiply and spread and a typical syphilis rash appears. It is recommended to go to the dermatology and venereal disease department of a regular hospital for examination and treatment after high-risk sex to prevent the condition from deteriorating. In addition, pay attention to cleanliness, avoid high-risk sex, and exercise diligently to improve your immune system.