Syphilitic is exclusive contagion source. Sexual contact is infected occupy 95% . Basically infect by breakage through sexual intercourse, syphilis helicoid abounds in to damage the surface at skin mucous membrane, also see in fluid of saliva, galactic, seminal, make water.
　　
Be in without remedial patient infection provides infectivity most inside a year, follow disease period to lengthen, infectivity is smaller and smaller, the person that disease period exceeds 4 years, through the gender the contact does not have infectivity.
　　
Syphilis helicoid Yi Ke is invaded through dry skin and complete mucous membrane. Minority can be infected through the intimate contact such as kiss, lactation, but must be in osculatory place with syphilis helicoid. Because syphilis helicoid is sex of oxygen of be disgusted with, outside body live not easily, and right dry very sensitive, infect what pass all sorts of implements secondhand, this kind of possibility is few. Syphilis patient is like the person that offer blood when blood transfusion can infect at the receptor.
　　
Congenital syphilis is to suffer from luetic pregnant woman to go and be infected through placental blood fetal. Be in commonly gravid before 4 months, as a result of the protective action of alimentary body, syphilis helicoid cannot be passed, before reason is gravid 4 months are fetal be not affected, later alimentary body is atrophic, syphilis helicoid can be entered through placenta infect inside fetal body fetal.

Previous:Infection syphilis how long comes on
Next：Careful syphilis causes mental disease