December 18, 2014 — The rate of reported chlamydia cases in the U.S. per 100,000 residents declined by 1.5% from 2012 to 2013, marking the first reported decrease in the infection rate since national reporting began, according to an annual CDC report on sexually transmitted infections released Tuesday, MedPage Today's "The Gupta Guide" reports.
For the report, researchers analyzed data on chlamydia, gonorrhea and syphilis, the three STIs for which there are dedicated federal control programs and national reporting in place, as well as several other STIs. The researchers used data provided by state and local STI programs and other projects that monitor STIs, in addition to national surveys conducted by the federal government and private organizations.
According to CDC, the data likely represent an underestimate of STI infection rates as the result of incomplete reporting and diagnosis (Smith, "The Gupta Guide," MedPage Today, 12/16). Overall, CDC estimates that there are 20 million new cases of STIs in the U.S. annually, including STIs that are not regularly reported to CDC, such as the human papillomavirus (Wetzstein, Washington Times, 12/16).
Key Findings on Chlamydia
Overall, the report found that although the rate of reported chlamydia cases declined last year, it was still the most commonly reported STI, with 1.4 million new cases (Stobbe, AP/ABC News, 12/16). Specifically, CDC found that there were roughly 446.6 cases of chlamydia per 100,000 people. By comparison, the chlamydia rate increased from 1993 through 2011 from 178.0 to 453.4 cases per 100,000 people, then held steady at 453.3 per 100,000 people in 2012.
CDC also found that reported cases of chlamydia declined among women by 2.4% between 2012 and 2013 and increased among men by 0.8%.
However, CDC noted that women continued to report a higher overall rate of the infection than men, at least partly because they are more likely than men to undergo screening for the infection. Specifically, CDC said there were about 993,348 cases reported in 2013 among women, accounting for a rate of 623.1 per 100,000 women.
CDC also found that there were 333,004 reported cases of gonorrhea in 2013.
According to CDC, the gonorrhea rate declined by 0.6% compared with the 2012 rate, but increased by 8.2% compared with the 2009 rate. CDC said the reported rate of gonorrhea among women deceased by 5.1% compared with 2012, while it increased among men by 4.3%.
In addition, CDC found that there were 17,535 reported U.S. cases of primary and secondary syphilis in 2013, increasing by nearly 11% since 2012 and marking the highest rate since 1995.
CDC noted that compared with 2012, the syphilis rate among women held steady at 0.9 cases per 100,000 in 2013, while increasing among men by 12%, from 9.2 to 10.3 cases per 100,000 men ("The Gupta Guide," MedPage Today, 12/16).
Researchers said cases of syphilis among men who have sex with men accounted for much of the overall rate increase among men (Washington Times, 12/16). Further, CDC found 52% of MSM who reported having syphilis also reported having HIV, compared with 9.9% of men who have sex with women and 5.2% of women ("The Gupta Guide," MedPage Today, 12/16).