The main source of infection of syphilis is the person with syphilis. As for the ways of transmission, there are several: 1, sexual contact transmission: such as close contact between husband and wife, sexual partners; 2, mother and child transmission: such as the mother infected with the virus, during pregnancy, the syphilis spirochete can be transmitted to the fetus through the placenta, causing fetal malformation, stillbirth or miscarriage; 3, blood transmission: if the blood source is not well guaranteed, in the process of blood transfusion, the blood with syphilis spirochete may be transfusion to healthy people. Blood transfusion transmission is generally for blood that has been refrigerated for less than 3 days, and is somewhat infectious. If it is not fresh blood, if refrigerated for a long time, the infectiousness is relatively small, but if it is within 3 days, it is certainly infectious; 4. Breastfeeding transmission: syphilis spirochetes can be transmitted to the newborn or to the baby through this route. Many patients found syphilis, especially during pregnancy, such as effective treatment in the first 3 months of pregnancy or the second 3 months, after the birth of the baby, can be normal breastfeeding, do not need to worry too much, after all, breast milk is very useful for the health of the baby. Therefore, after effective treatment, it is completely safe to breastfeed; 5. Close contact transmission: Sexual transmission accounts for 90%, or even 95%, of syphilis transmission. A few may be through some close contact, such as the contact of secretions, underwear underwear contact, sharing bath towels, there is also a certain risk of infection. Another problem is that syphilis is very contagious in the early stages and very weak or has disappeared in the late stages. Stage I syphilis hard chancre, stage II syphilis rash and flat warts are very contagious. The copper-red spots on the palms of the hands and feet have a certain amount of syphilis spirochetes on the surface, and there is a certain chance of infection through shaking hands. However, after adequate treatment, the contagiousness will be greatly reduced. After syphilis infection, even without very effective treatment, there is no contagiousness between couples after 4 years. This is because the syphilis spirochetes have penetrated deep into the internal organs, and there are no more syphilis spirochetes on the skin surface or mucous membrane surface, but it is not that the disease has been cured, but that the syphilis spirochetes have moved to other parts of the body and the skin mucous membrane is no longer a host site. So the longer the time, the less infectious syphilis will be, and even with the extension of time, the infectiousness will gradually disappear. Therefore, patients with advanced syphilis after treatment, do not have too much guilt, do not have too much psychological pressure, after effective treatment or after a longer period of illness, can live a normal life.