Baltimore has by far the country's highest rate of syphilis, at more than 30 times the national average, and the city blames the use of crack cocaine and the trading of drugs for sex. Baltimore also topped the nation in gonorrhea, with a rate nine times the national average. The Centers for Disease Control and Prevention in Atlanta ranked the 20 cities with the highest rates of the two sexually transmitted diseases last year. Overall, the CDC said, both diseases have been reduced to all-time lows in the U.S. Syphilis has nearly been eradicated in all but a few cities. New Orleans and New York are among other cities that saw syphilis cases rise this decade.