Chlamydia is one of the most common STDs and is especially widespread among sexually active teens and young adults. It is estimated that over 1 million people in the US are currently infected. Not everyone with chlamydia has symptoms, so most people don’t know that they’re infected. Chlamydia can cause serious reproductive problems and increases the risk of contracting HIV. To prevent chlamydia, use condoms and get routine STD tests. KnoWyo.org offers convenient and low-cost testing options here.