9. Killeen, Texas
Total STDs: 4,887
Total STDs per 100,000: 1512.83
This may be a coincidence, but there is more than one city on our list of most sexually diseased cities in America that has a military post nearby. Killeen is one as well. When it comes to specific sexually transmitted diseases, 3,496 people suffer from chlamydia, 1,361 from gonorrhea and 30 from syphilis.