Based on recent data, the CDC recommends that clinicians screen all sexually active young females annually for chlamydia.
Elizabeth Torrone, PhD, of the CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, and colleagues used data from the 2007-2012 National Health and Nutrition Examination Survey to determine the overall prevalence of chlamydia among participants aged 14 to 39 years and by sexual behaviors and demographic characteristics. Survey participants were interviewed and medically examined. Complete data were available for 8,330 participants.
Overall, there were an estimated 1.8 million chlamydia infections nationwide, indicating an overall prevalence of 1.7% (95% CI, 1.4-2).
Infection was associated with age, race and ethnicity, income, marital status, number of sexual partners, and education level.
Chlamydia was nearly seven times as common among non-Hispanic blacks compared with non-Hispanic whites, with a prevalence rate of 6.7 (95% CI, 4.2-10.6) among non-Hispanic blacks. Mexican Americans had a prevalence rate of 2.9 (95% CI, 1.7-5.1) and were nearly three times as likely to have chlamydia compared with non-Hispanic whites.
Sexually active participants who reported having one sexual partner in the last year had a lower prevalence of chlamydia compared with participants who reported two or more sexual partners, 1.4% vs. 3.2%.
Prevalence rates were similar among sexually active females who used oral contraceptives or medroxyprogesterone acetate and women who did not use those contraceptive methods.
Prevalence of chlamydia decreased with age among sexually active females (P<.05).
Overall, 4.7% of sexually active females aged 14 to 24 years, the targeted population for chlamydia screening, had chlamydia. Approximately one in seven non-Hispanic black females who were sexually active and aged 14 to 24 years had chlamydia, with a prevalence rate of 13.5%. One in 22 Mexican-American females who were sexually active and in the targeted age group had chlamydia, indicating a prevalence of 4.5% vs. 1.8% among non-Hispanic white females, in which one in 55 had chlamydia.
Overall chlamydia prevalence rates among participants aged 14 to 39 years was similar across the three survey cycles included in the study. Rates were 1.6% in 2007-2008, 1.7% in 2009-2010, and 1.9% in 2011-2012.
“Currently, the US Preventive Services Task Force recommends annual screening of all sexually active females aged less than 25 years and screening of older women at increased risk (eg, women who have new or multiple sex partners). … Additionally, CDC recommends that men who report rectal sex should be screened at least annually and that targeted urogenital screening of sexually active young men in high prevalence clinics might be considered,” the researchers concluded.
Disclosure: The researchers report no relevant financial disclosures.