12. Bronx, New York
Total STDs: 19,847
Total STDs per 100,000: 1409.115
Rather than viewing the city of New York as a whole, our source looked boroughs of New York separately. This caused the Bronx with 1.4 million population to end up on our list of most sexually diseased cities in America. 16,116 people are infected with chlamydia, 1,964 with gonorrhea and 235 with syphilis.