Among the most alarmng stats: Eighty-five percent of Americans with herpes (42 million people) don't know it. That statistic and the others shared below (courtesy a study from the retailer Adam & Eve) are disturbing reminders that HIV isn't the only sexually transmitted disease that people need to protect themselves against.Of course, being HIV-positive is no protection; in fact it can increase your odds of catching another STD and can make symptoms of that infection worse.Check out this data on everything from how many people have STDs, what types are most prevalent, and what percentage of people tell their sexual partners about their STD status. "Unfortunately, sexually transmitted diseases are still a very real problem," Chad Davis, Marketing Director for AdamandEve.com said in a written statement. "Adam & Eve started as a condoms-by-mail company over 40 years ago, and condoms are still a major part of who we are. We encourage adults to educate themselves about the risks associated with unprotected sex."