Chlamydia is a common sexually transmitted disease caused by bacteria. You get it by having sex or sexual contact with someone who is infected. You are not born with chlamydia. Babies born to infected mothers can get eye infections and pneumonia from chlamydia. You can cure chlamydia with antibiotics. If you are sexually active, you can decrease your risk of getting it by using condoms. Experts recommend that women 25 and younger get a chlamydia test every year.