Syphilis is transmitted from person to person by direct contact with a syphilitic sore, known as a chancre. Chancres can occur on or around the external genitals, in the vagina, around the anus , or in the rectum, or in or around the mouth. Transmission of syphilis can occur during vaginal, anal, or oral sex.

Which STD starts with a chancre?

Secondary syphilis rash on the back. Primary stage syphilis sore (chancre) on glans (head) of the penis. Primary stage syphilis sore (chancre) inside the vaginal opening.

Which STD STI can cause painful?

What it is: Herpes is a viral infection that causes painful sores in the genital area. It's spread through skin-to-skin contact. Once you're infected, you have the virus for the rest of your life. Symptoms: Women and men may have tingling, pain, or itching around the vagina or penis.