4. Philadelphia, Pennsylvania
Total STDs: 26,151
Total STDs per 100,000: 1689.77
When it comes to total number of STDs, the largest city of Pennsylvania State is without any competition on our list of most sexually diseased cities in America. There are 26,151 people infected from the whole population of 1.5 million. 19,570 people suffer from chlamydia and 6,303 from gonorrhea. There are also 278 those infected with syphilis.
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