Sexually transmitted diseases (STDs) are a blanket description for nearly twenty-five diseases that are spread primarily by sexual activity. STDs are called a "hidden" epidemic in the United States and affect nearly sixty-five million people. The Centers for Disease Control (CDC) estimated in 1999 that almost fifteen million new cases of STDs occur each year and that teenagers are the group most often infected.

The spread of STDs has been increasing in the United States for many years. The instance of genital herpes among white teenagers, for instance, increased five times between the 1970s and 1990s. By the end of the 1990s, the CDC reported that more than one in five Americans had genital herpes. The rate of increase is tied to the numbers of people with multiple sexual partners and the number of diseases, such as chlamydia and genital herpes, that an infected person...