Approximately 50% of infected males and 80% of infected females are asymptomatic (no symptoms) by Chlamydia trachomatis infection. Thus patient may not take treatment thus, and can have complications like infertility later on or transmit the disease to partner.
Please feel free for your follow up questions.
The usual course is that the first infection will give you symptoms in 1-3 weeks. If it does not give you symptoms in the first instance they will lie dormant (means no signs and symptoms), but still destroy the internal lining of the genital tissues. All this time they can pass or transmit the infection to other partner. Usually flares are not seen after the dormant period.