Stage I syphilis, mainly after the syphilis spirochete enters the human body through unsafe sexual contact, such as sexual contact, the syphilis spirochete is mainly in the genital area, most commonly the glans and coronal groove in men; the labia majora and vaginal opening in women, in these locations, the pathogen appears to multiply locally and an inflammatory reaction occurs, while at the same time right at the time of infection, the syphilis spirochete can pass through the lymphatic vessels and enter the At the same time, during the infection, the syphilis spirochetes can enter the local lymph nodes through the lymphatic vessels, causing local lymph node enlargement. The symptoms of syphilis include two aspects: 1) local inflammatory reaction, mainly manifested as hard chancre; 2) local lymph node enlargement. The patient can feel it by himself, and it is like the auricle, like the harder degree of cartilage. The scientific name of this rash is hard chancre because it is a little hard to the touch, unlike other ulcers which are soft to the touch, so this is one of the characteristics of hard chancre. The second feature is that if you have sexual contact, you can feel swollen lymph nodes on both sides of your thighs, i.e. your groin, which are the size of soybeans or beans. In addition to the genital area and the perianal area, if there is sexual contact with other parts of the body, such as oral sex, the hard chancre may appear on the lips and inside the mouth; if the breast area, the hard chancre may also appear.