The infection may be passed from person to the person through sexual intercourse, but the actual cause is a bacterium called “Chlamydia trachomatis”. This bacteria, when passed from one person to another, can live inside the vagina, penis and rectum, and can then be found in a man’s semen and a woman’s vaginal fluids (hence, how it is passed during sex).Although it only takes coming into contact with the infection once in order to acquire it, you heighten your risks by having unprotected sex with multiple different partners. You should get yourself tested regularly; once a year or each time you have sex with a new partner.