What does Chlam mean?

After a restless night he decided to get tested for chlam after all.

Dutch student slang. This is a Dutch word. You will hear it a lot at Dutch universities, student associations and in student houses.

You mostly get it from unprotected sex and at first you often don't notice it. Getting tested is free or cheap at the GGD in many Dutch cities. And a condo helps you avoid it in the first place.