“The Centers for Disease Control and Prevention says young people ages 13 to 24 make up approximately one in four new HIV infections in the US, and about 60 percent of those infected don’t know they have the disease.” Those are facts that many teens don’t know about. And it turns out that — according to a recent survey — a third of them don’t even know that HIV is an STD. This is either a truly remarkable stat or a really bad survey.