Granny tells Uncle Ferd to stay away from dem ladies dat gots the nasties... Chlamydia Sets U.S. Record For Most Cases of Reportable Disease April 8, 2014 A total of 1,422,976 new cases of Chlamydia trachomatis were reported to the Centers for Disease Control and Prevention (CDC) in 2012, the largest number of reported cases for any notifiable disease in the U.S.," a CDC spokeswoman told CNSNews.com.