It is caused by a bacterium (spirochete), Treponema Pallidum.
How does it manifest itself?
The incubation period varies between 10 and 90 days (average 21 days) after which several clinical pictures may occur: small, painless ulceration, at the point where the infection occurred (genitals or mouth), of short duration.
How is it transmitted?
Through direct contact with infected wounds (vaginal, anal and oral sex).
It can be transmitted from the mother to the fetus during pregnancy, with possible death of the fetus in the uterus or the birth of a child with congenital syphilis.
With a blood test to search for antibodies, on average, 40 days after infection. Sexual partners must also be controlled.
It is treated with antibiotics.