Chlamydia can affect both men and women and is typically transmitted through unprotected sexual intercourse (without a condom). It is more common in young people, particularly young women, but men can also be affected. Chlamydia can be passed onto sexual partners during oral, vaginal or anal sex with someone who has the infection and a woman can also pass the disease onto her baby during childbirth. It is also possible to be reinfected with chlamydia even if you have been treated in the past if you have unprotected sex with someone who has it.
As a bacterial infection, it can also be passed on through the following:
- Genital to genital contact with an infected person without penetration or ejaculation
- Sharing sex toys without cleaning them in between uses or not using a new condom each time they are used
- Eyes may be affected if they come into contact with infected vaginal fluid or semen