The saliva, or saliva, of a person with syphilis theoretically contains a certain amount of syphilis spirochetes, the pathogens of syphilis. Syphilis spirochetes are usually found in the skin and mucous membranes of patients, as well as in semen, breast milk, saliva, and blood. Generally, syphilis is less likely to be transmitted through saliva because the spirochetes are less abundant in saliva and cannot survive in the external environment for long periods of time, but there is a risk of infection if you kiss or have other oral intimate behavior with a person with syphilis. The risk of infection is especially high for patients in the first stage of syphilis, where hard chancre may appear at the mouth, lips and tongue, when the mucous membrane in the mouth is damaged and the content of syphilis spirochetes increases, making it more infectious. Therefore, it is recommended that patients infected with syphilis should be actively and reasonably isolated and treated, and sexual partners should also be investigated and treated together, and should be re-examined according to medical advice after being cured. The prevention of syphilis in daily life can start from the transmission of syphilis, pay attention to avoid unsafe sex; for pregnant women with syphilis to give active treatment to prevent the transmission of syphilis to the fetus; donate blood need to carry out a full body examination, blood examination, to the regular blood collection points; if there are syphilis patients around, should pay attention to avoid close contact with syphilis patients.