Chlamydia and gonorrhea are the two most common diseases among those doctors must report in the United States. And the 1,030,911 cases of chlamydia in 2006 are the highest ever recorded for any nationally reported disease in any year, the officials said in releasing their annual report on
sexually transmitted diseases. They said that because of underreporting, a more accurate estimate is 2.8 million new chlamydia cases annually.
About 19 million new cases of all kinds of sexually transmitted diseases occur in this country each year, but only the three are nationally reported.
Genital herpes, papillomavirus and trichomonas infections account for the vast majority of cases, but doctors are not required to report them nationally.
http://www.nytimes.com/2007/11/14/he...us&oref=slogin