Syphilis is a chronic infectious disease caused by the syphilis spirochete. It is mainly transmitted through sexual contact and blood, and can be harmful, invading all tissues and organs of the body or transmitted through the placenta, causing stillbirth, miscarriage, premature birth and fetal syphilis.
The only source of infection for syphilis is the patient with syphilis. The spirochetes are present in the skin lesions, blood, semen, breast milk and saliva of patients. The common routes of transmission are sexual contact (about 95% of cases) and mother-to-child fetal transmission. A small number of patients can also be infected by medical route, blood transfusion, kissing, hand shaking, breastfeeding or contact with contaminated clothing or utensils.